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The development of drawing in children with congenital focal brain injury: Evidence for limited functional recovery
\
Pergamon
PII] S9917Ð2821"85#99977Ð6
Neuropsycholo`ia\ Vol[ 24\ No[ 2\ pp[ 188Ð201\ 0886 Þ 0886 Elsevier Science Ltd[ All rights reserved Printed in Great Britain 9917Ð2821:86 ,06[99¦9[99
The development of drawing in children with congenital focal brain injury] Evidence for limited functional recovery JOAN STILES\ DORIS TRAUNER\ MURRAY ENGEL$ and RUTH NASS% Department of Cognitive Science\ University of California\ 8499 Gilman Drive\ La Jolla\ CA 91982!9098\ U[S[A[^ $New York Hospital\ Cornell Medical Center\ New York\ U[S[A[^ %New York University Medical Center\ New York\ U[S[A[ "Received 11 November 0882^ accepted 01 July 0885#
Abstract*Children with pre! or perinatal injury to right hemisphere "RH# brain regions show impairment of spatial integrative functions similar to that observed among adults with comparable injury[ Unlike adults\ children show considerable improvement with development on a range of spatial construction tasks which require spatial integration[ Such gains could re~ect true recovery of spatial integrative abilities[ Alternatively\ the improvement could be more limited in scope\ re~ecting the development of compensatory strategies which are task speci_c and allow the children to circumvent\ rather than overcome\ their primary spatial disorders[ The studies presented here examined this distinction within the context of drawing tasks in which the child was _rst asked to draw a house and then an impossible house[ The impossible house task was designed to examine the extent to which children rely on graphic formulas in generating organized drawings[ The results showed that while all of the children with RH injury make considerable progress in free drawing into the school age period\ they are very reliant on the use of graphic formulas[ When given a task which requires them to alter their drawings\ they did not change the spatial con_guration of the depicted object[ Rather they found alternate ways to render the object {impossible|[ Þ 0886 Elsevier Science Ltd[ All rights reserved[ Key Words] plasticity^ brain injury^ drawing[
ever\ little is known about the developmental course or process of functional recovery in the child population[ The assessment of functional recovery from a behavioral perspective must take account of the process as well as the product of behavior[ Similar outcomes may be achieved in di}erent ways[ Thus\ when mastery is observed it is important to document whether it was achieved[ The present study is a _rst attempt to focus on this aspect of recovery by examining improvement on a drawing task among children with RH injury[ The spatial integrative de_cits of preschool children with RH injury have been particularly striking on free drawing tasks[ In an earlier study ð18Ł\ we reported data from a drawing task involving two young children with RH injury[ The children were 4 years old when the draw! ings were produced\ and each showed marked de_cits of spatial integration[ Speci_cally\ in their drawings of houses and people\ the children included appropriate parts but failed to arrange those parts into spatially inte! grated whole forms[ The parts were scattered around the page or strung together in random arrays[ These kinds of spatial integrative de_cits were not observed in age and
Introduction Early focal brain injury results in subtle but speci_c forms of spatial cognitive de_cit ð13Ð18Ł[ Speci_cally\ children with right hemisphere "RH# injury have di.culty with spatial integration[ While they can identify and segment the parts of spatial forms\ they are impaired in their ability to organize those parts into well!formed spatial con_gurations[ By contrast\ children with left hemisphere injury "LH# are impaired in their ability to process pattern detail[ The de_cits observed in children are consistent with the patterns of de_cit observed among adults with similar injuries[ However\ impairment in the child popu! lation is generally milder than that of adults\ and pre! liminary data suggest that children are better able to compensate for their de_cits than adults[ The observation that children are better able to com! pensate for cognitive or linguistic de_cits is not new "e[g[ ð0Ð6\ 00\ 02\ 04\ 05\ 07Ð10\ 22Ł[ Many\ primarily retro! spective\ accounts of behavioral functioning following early focal brain injury converge on the view that capacity for recovery is greater among children than adults[ How! 188
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J[ Stiles et al[:The development of drawing in children with congenital focal brain injury
IQ matched children with LH injury whose performances were comparable to that of normal 4!year!olds[ The drawing anomolies observed in the children with RH injury are consistent with those reported by Swindell and colleagues ð29Ł for adult patients[ These authors describe their patients| drawings as {{scattered\ fragmented\ and disorganized|| "p[ 08#[ We have collected a considerable body of drawing data since our original _ndings were reported[ Among the longitudinal data obtained were drawings of houses[ These data are the focus of the current studies[ Across the series of three studies\ we examined change in both the children|s free drawing of houses and in their responses to a probe question designed to elicit an alternative ren! dering of houses[ The _rst measure was designed to assess mastery on a speci_c task\ while the second examined ~exibility or reliance on speci_c drawing strategies[ Study 0 was a longitudinal study of house drawing[ It was designed to determine whether the children|s drawings would improve with development\ and whether there would be consistency over time in the way houses were depicted[ Study 1 was a cross!sectional study in which performance on the house drawing task was compared to performance on a task in which children were asked to draw a house that was di}erent from their usual one[ This study provided data from both a large sample of normally developing children on the elicited task\ and a cross!sectional sample comparing performance of the lesion groups with normal controls on the free and elicited drawing tasks[ Study 2 provided longitudinal data on performance on the elicited task[
Descriptions of subjects The three studies described in this report present data from many of the same subjects[ For brevity\ a single subject description section providing information on all subjects included in the three studies is included here[ All the children in the brain injured groups sustained unilateral focal injury either prenatally or during the _rst six months of life\ as documented by a CT or MRI scan[ Children were excluded from the study if they dem! onstrated evidence of multiple lesions\ di}use damage or conditions which may have caused global brain damage\ such as a viral infection\ encephalitis\ or anoxia[ Table 0 provides descriptions of all of the children with RH or LH injury participating in the current series of studies[
Study 0] Longitudinal data from a house drawing task The purpose of this study was to document devel! opmental change in performance on a free drawing task among children with unilateral focal brain injury[ Our earlier study ð18Ł indicated that at 4!years of age children with RH but not LH injury have di.culty in drawing simple objects[ In this study we examine performance on
this task through the school!age period[ Longitudinal series of house drawings collected in a free drawing task are presented for 5 children with RH injury\ 5 with LH injury and 5 controls matched for age and IQ[ We selected children for whom we had a minimum of four data points spanning at least a 1!year period[
Longitudinal series of house drawings] Children with early LH injury Figure 0 shows the longitudinal series of drawings from children with LH injury[ The houses have an outer boundary\ and the parts are clearly depicted and appro! priately arranged within the house boundaries[ Although the drawings improve with age there is also a notable similarity in the drawings of individual children over time[ Consistent with studies of adults and normally developing children ð7Ð09\ 01\ 03\ 06\ 12\ 20\ 21Ł\ the children in this study appear to have developed graphic formulas for house drawing[ These formulas underwent modi_cation over time "note\ for example\ the intro! duction of 2!dimensional representation in several of the children|s drawings# but the similarity of drawings from one session to the next is evident[
Longitudinal series of house drawings] Children with early RH injury Figure 1 shows the house drawings produced by chil! dren with RH injury[ Consistent with our earlier study ð18Ł young children with RH injury initially had di.culty producing organized representations[ However\ with time\ considerable improvement was noted[ By age 5 or 6\ all of the children were able to generate organized and integrated drawings of houses[ Like the normal children and children with LH injury\ consistency across time in the way houses were depicted was also evident[ Thus despite initial di.culty on this task\ children with RH injury appear to have developed strategies for drawing simple pictures of houses\ very likely through the devel! opment of graphic formulas[ These data point to signi_cant functional improvement for the children with RH injury on this speci_c drawing task[ Their drawings improved markedly\ and that improvement persisted over time[ However\ to under! stand the phenomena of functional recovery it is necess! ary to assess not just whether a child has improved on a task or set of tasks\ but where possible to ask how the child has achieved that measure of success[ Children may be able to compensate on a speci_c task without actually overcoming the de_cit\ per se[ One possible marker of subtle persistent de_cit is the extent to which a child relies on a speci_c compensatory strategy[ That is\ is the child|s successful performance bound to a particular narrowly de_ned strategy or can the child deal more ~exibly with the spatial problem solving situation< Tasks which
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Table 0[ Summary of the neurological\ IQ and age data for children with early right or left unilateral focal brain injury
Subject Sex
Lesion Site
Lesion Onset
Seizures
IQ
Right Hemisphere prenatal
no
perinatal
yes
WISC III V094 P66 F89 WISC III V82 P53 F66 WISC!R V092 P091 F091 WISC!R V024 P095 F012 WISC III V65 P61 F61 WISC III V008 P66 F87 WISC III V62 P68 F62 WISC!R V007 P004 F008 WISC!R V79 P001 F83
MB
M
NS
M
frontal parietal*cortical and subcortical frontal*cortical and subcortical
MG
M
parietal*subcortical only
pre! or perinatal
no
RD
M
perinatal
no
PK
M
prenatal
yes
AP
M
prenatal
no
EM
F
frontal parietal temporal*cortical and subcortical frontal parietal temporal*cortical and subcortical parietal temporal*cortical and subcortical parietal*subcortical only
perinatal
no
JD
F
parietal temporal*subcortical only
peri
no
RH
M
frontal*cortical and subcortical
pre! or perinatal
no
PA
F
Left Hemisphere pre! or perinatal<
no
JP
M
perinatal
no
AG
M
parietal temporal occipital*cortical and subcortical frontal parietal temporal*cortical and subcortical frontal*subcortical only
perinatal
no
GC
M
temporal*cortical and subcortical
perinatal
no
DV
F
prenatal
yes
KQ
M
perinatal
no
NP
F
frontal parietal temporal*cortical and subcortical frontal parietal temporal*cortical and subcortical temporal*cortical only
pre! or perinatal<
no
SB
M
partietal*subcortical only
prenatal
no
JQ
F
parietal temporal occipital*cortical and subcortical
pre! or perinatal<
yes
WISC!R V092 P67 F89 WISC R V68 P73 F79 WISC!R V096 P012 F005 WISC!R V095 P094 F094 WISC!R V80 P89 F89 WISC!R V094 P85 F090 WISC!R V095 P84 F090 WISC!R V012 P005 F011 WISC!III V009 P004 F002
Subject] Studies 0 and 2
Age at Test "yr!mo#] Study 1
yes
6Ð00
no
7Ð4
yes
8Ð1
yes
8Ð3
yes
8Ð6
no
09Ð9
yes
09Ð5
yes
00Ð0
no
02Ð2
no
6Ð1
no
7Ð0
yes
7Ð0
yes
7Ð1
yes
8Ð09
yes
09Ð9
no
09Ð2
yes
09Ð09
yes
04Ð3
In some cases it is unclear whether the onset of the stroke was in the pre! or perinatal period[ These are noted as {pre! or perinatal<|
require the children to use strategies other than the ones they typically employ\ can reveal a great deal about the facility with which children can solve spatial problems[ Excessive reliance on a single strategy can be a marker of residual de_cit[ Study 1 was designed to explore these issues[
Study 1] Cross!sectional data from the {impossible house| task One notable feature of the drawing series for each of subjects in Study 0 was the consistency of the drawings over time[ Drawings produced over a period of years maintained a marked similarity[ One interpretation of this consistency is that the children develop graphic for!
mulas for drawing common objects such as houses[ The use of graphic formulas is a common and well!docu! mented drawing strategy among normal adults and chil! dren ð7Ð09\ 01\ 03\ 06\ 12\ 20\ 21Ł[ Graphic formulas are de_ned as the procedure or set of implicit rules by which a graphic object is produced[ The hallmark of the graphic formula is the relative inaccessibility of the production procedures which underlies it ð03Ł[ Consider\ for example\ the production of a 4!pointed star[ Although the initial learning of the form may have been quite painstaking\ it constitutes a graphic formula for most adults[ A typical reproduction sequence begins at one vertex "usually the same vertex for a given individual# and the _ve lines comprising the _gure are generated in turn[ The formulaic nature of this graphic production can be conveyed by asking that the drawer begin from any vertex other than
291
J[ Stiles et al[:The development of drawing in children with congenital focal brain injury
Fig[ 0[ The longitudinal series of house drawings are presented for six children with LH injury[ Note the consistency over test session in the shape and organization of the drawing[
the usual starting point[ This exercise generally results in an initial delay as the drawer attempts to make explicit the usually implicit set of rules for drawing the form[ From the earliest stages of drawing development\ at about age 1\ normal children produce graphic formulas ð12Ł[ Once mastered\ graphic formulas o}er a means of simplifying the problem of graphic representation by eli! minating the requirement to analyze the spatial properties
of the form to be represented[ Thus\ they o}er a poten! tially useful compensatory strategy for children with speci_c spatial analytic de_cits[ It is possible that the improvement observed in the free drawings of children with RH injury involves the gradual mastery of a core set of graphic formulas\ rather than more general improvement in spatial analytic abilities[ If this is the case then\ while the children clearly demonstrate functional
J[ Stiles et al[:The development of drawing in children with congenital focal brain injury
292
Fig[ 1[ The longitudinal series of house drawings are presented for six children with RH injury[ For those children tested in the late preschool period "P[K[\ M[B[\ J[D[ and R[D[# the initial disorganization of the drawing is evident[ In each case the drawings improve with development[ Note the consistency of the drawing across testing sessions[
recovery\ the degree of recovery may be more restricted than the data _rst suggest[ In Study 1\ we used a drawing task adapted from one developed by Karmilo}!Smith ð03Ł in a study of normally developing 4! to 09!year!old children[ In this task\ the child _rst draws a picture of a house\ and is then asked to draw {{an impossible house\ a house that couldn|t possibly be\ a make!believe house||[ The normally developing children in Karmilo}!Smith|s study produced a range of fanciful responses to this request\ many of
which involved spatial recon_guration[ If the mastery of house drawing observed among children with RH injury depends on the use of a graphic formula\ and does not re~ect a more general improvement in their spatial ana! lytic abilities\ then their performance on the {impossible house| task should di}er systematically from that of nor! mal controls and children with LH injury[ The primary di}erences should lie in the types of strategies they use to generate impossible houses[ Speci_cally\ children with RH injury should show limited use of strategies which
293
J[ Stiles et al[:The development of drawing in children with congenital focal brain injury
involve re!analysis of the spatial array[ Rather than adopting strategies involving con_gural distortion of the parts and wholes of an array\ the children should use strategies that allow them to retain the con_gural organ! ization of their graphic formulas but still render the house impossible[
Study 1a] Cross!sectional data from normally developing children Karmilo}!Smith ð03Ł described a range of drawing strategies used by normally developing 4! to 09!year!olds on the impossible drawing task[ As indicated in Study 0\ the children with RH injury still exhibited considerable di.culty in simple house drawing at age 4\ thus we did not begin to collect data from the more di.cult imposs! ible house task until age 5 to 6\ and we continued data collection beyond age 09[ For this reason\ we collected a separate sample of data from 004 normally developing children in the 5! to 04!year age range\ and we examined the type and distribution strategies they used to create impossible houses[ Study 1a presents those data[
Method Subjects The sample for this study included 009 children between 5! and 04!years of age[ A total of 44 children constituted a younger group that ranged in age from 5!years "5!9# to 7!years and 00! months "7!00#\ and 59 children constituted the older group that ranged from 8!9 to 04!9[ The children were tested in a variety of school and laboratory settings[
Scoring Each drawing was scored according to the drawing strategy or strategies used to produce an impossible house[ The scoring system was adapted from Karmilo}!Smith\ and consisted of the following eight categories] 0[ Con_`ural distortions including "a# scrambling the parts\ "b# distortion of the outer form and "c# distortion of the parts[ 1[ Rotation[ 2[ Part deletion "a# or repetition "b#[ 3[ Reduction[ 4[ Object transformation which involved either turning a second object into a house by adding doors and windows\ or turning a house into something else by adding atypical features such as facial features[ 5[ Object substitution which involved the simple replacement of one object for another without transformation[ 6[ Placement in an atypical location such as on the moon or under the earth[ 7[ Verbal description which involved production of a typical house accompanied with a description of why the house was impossible[ Typical examples of each of these categories drawn from the
sample of normally developing children are shown in Fig[ 2[ It was possible for a child to include more than one strategy in his:her drawing[ For example\ a child could distort the overall con_guration and turn it upside!down[ In scoring\ each drawing was assigned all appropriate category scores[ All 004 drawings could be assigned to at least one of the eight categories[ The drawings were scored by a single rater[ To assess reliability\ 14) of the drawings were scored by a second rater[ Scoring reliability was 099)[
Results and discussion The purpose of this study was to determine the fre! quencies with which normally developing children use the strategies originally described by Karmilo}!Smith as typical responses to the instruction to draw an impossible house[ Table 1 shows the frequency distributions across the eight categories for the full sample\ and the dis! tributions for the younger and older groups separately[ Note that because some children used more than one strategy in their drawing\ the percentages within each distribution sum to more than 099)[ Thus the data re~ect the percentage of children who used a strategy\ rather than the proportional use of strategies across the group[ Within the full sample\ 81 drawings were assigned to a single category\ 11 were assigned to two categories and 0 was assigned to three categories[ It is evident from the table that the predominant strategy among normally developing children involved con_gural distortion of the parts\ the whole or the relation between the parts and the whole[ In over half the cases "20 of 46# con_gural distortions involved some combination of part distortion\ whole\ distortion and scrambling[ There were only _ve cases in which only the parts were distorted[ The remain! ing seven strategies were all used regularly\ though less frequently\ by normally developing children\ and all were clearly viable strategies for rendering a house {imposs! ible|[ Nonetheless\ they were nondominant strategies[ Finally\ note that the distribution of strategy use among older and young children was very similar[
Study 1b] Cross!sectional data from children with early focal brain injury This study examined the performance of a cross!sec! tional sample of children with unilateral focal brain injury on the {impossible houses| task[ The purpose was to examine all the possible strategies used by the di}erent groups in solving the problem of graphically depicting an impossible house[
Method Subjects This study focused on a cross!sectional sample of children with unilateral focal brain injury in the 6! to 04!year age range[
J[ Stiles et al[:The development of drawing in children with congenital focal brain injury
294
Fig[ 2[ All of the impossible house drawings were scored as representing eight categories[ An example of a typical drawing from each category is shown[ These examples were drawn from the cross!sectional sample of 004 normally developing children included in Study 1a[ Note that a drawing could be assigned to more than one category score[
All of the children listed in Table 0 were included in this sample[ There were nine children in each group[ The age at test for each child is indicated in the table[ The two lesion groups were comparable in age "M 8!00 for the RH and 8!7 for the LH group# with the following IQ means] VIQ] PIQ] FSIQ]
LH 092[2 LH 099 LH 091
RH 099[11 RH 78[2 RH 83[1
In addition\ a group of 01 normally developing controls of comparable age "M 8!4# and FSIQ "M 009#\ VIQ "M 001[56# and PIQ"M 095# were included in the analyses[
Procedure Each child was asked to draw a house\ and then an impossible house[ Drawings were scored according to the system described in Study 1a\ above[
Results and discussion Study 1a indicated that the most common strategy for creating an impossible house among normally developing
295
J[ Stiles et al[:The development of drawing in children with congenital focal brain injury Table 1[ Distribution of category usage by 004 normal 5! to 04!year!old children
Category 0 Con_g[ Dist[ Scramble Whole Part 1 Rotation 2 Part Del:Rep 3 Reduction 4 Object Conv[ 5 Form[ Sub[ 6 Placement 7 Verbal
All Children "n 004# Percent of Number of uses drawings 46 06 30 20 01 07 00 04 4 07 3
Ages 5Ð7\ 00 "n 44# Percent of Number of uses drawings
38[5
09[3 04[6 8[5 02 3[2 04[6 2[4
children was distortion of the spatial con_guration[ It was predicted that children with RH injury would have di.culty using this strategy because it requires re!analysis of the spatial array[ Chi squared analysis was used to examine the frequency of usage of the con_gural dis! tortion strategy "Category 0# versus the other seven stra! tegies[ The results of the analysis showed signi_cant di}erences between the groups[ The RH group used the con_gural distortion strategy signi_cantly less often than normally developing children or children with LH injury\ X1 7[06\ P³9[94[ Figures 3 and 4 show the possible and impossible drawings of the children with LH and RH injury\ respectively[ The subject|s initials and age at test is noted at the top left of each child|s possible house drawing^ the strategy category "0Ð6\ see above# is noted at the bottom left of the impossible drawing[ The draw! ings of the LH children were indistinguishable from those of children in the normally developing group in terms of type and distribution of strategies[ Note that the children with RH injury generally used strategies that are typical of normally developing children\ but they di}ered in the distribution of strategies used[ Speci_cally\ only one of the children with RH injury "M[G[# used con_gural dis! tortion[ In addition\ one of the children|s drawings "E[M[# did not _t easily into any of the strategy categories[
Study 2] Longitudinal data from the {impossible house| task Study 2 was intended as an expansion of the _ndings from Study 1b[ This study focused on the longitudinal series of {impossible house| drawings from the same six children with RH injury whose free drawings were pre! sented in Study 0[ One data point from each of these children was included in the analysis from Study 1b[ The purpose of this study was to provide a more extensive body of data on the performance of children with RH injury\ and to demonstrate the persistence of their failure to use con_gural strategies on this task[ For complete! ness\ {impossible house| data from the six children with
13 5 10 01 2 8 5 8 0 09 1
32[5
4[4 05[3 09[8 05[3 0[7 07[1 2[5
Ages 8Ð04 "n 59# Percent of Number of uses drawings 22 00 19 08 8 8 4 5 3 7 1
44
04 04 7[2 09 5[6 02[2 2[2
LH injury included in Study 0 are presented brie~y at the beginning of this section[
Longitudinal series of {impossible house| drawings] Children with early LH injury Figure 5 shows the longitudinal series of {impossible house| drawings from six children with LH injury[ The range of strategies used in these series approximated those found among the large cross!sectional sample of normally developing children reported in Study 1a[
Longitudinal series of {impossible house| drawings] Children with early RH injury The impossible house drawings of six children with RH injury are shown in Fig[ 6[ P[K[ was _rst asked to draw an impossible house at age 8!0[ At ages 8!0\ 8!6 and 09!0\ he used the object substitution strategy[ At ages 00!0 and 01!1\ P[K[ used the atypical location strategy\ placing the house on a cloud\ a roof and Mars\ re! spectively[ At 00!6 he said that the house was impos! sible because it is impossible for someone to _t under the roof[ At 4!09 M[B[ was asked for the _rst time to draw an impossible house[ His response was to draw a ~ower\ which was scored as a object substitution response[ Object substitution is a very infrequent response among normal children[ Yet it is one that M[B[ used three time in this series[ Two other strategies were evident in M[B[|s drawings[ At age 5!3\ when asked to draw an impossible house\ he gleefully returned the blank paper to the exper! imenter and announced he had drawn an invisible house[ When pressed to draw something\ he produced an object substitution[ He drew a person and labeled it a house[ At 6!00 M[B[ used a rotation strategy which persisted to the next session[ In the _nal session he used a reduction strategy[ He attached two little houses to the big one[ M[G[|s _rst attempt at an impossible house at age 7!9
J[ Stiles et al[:The development of drawing in children with congenital focal brain injury
296
Fig[ 3[ The impossible house drawings from the cross!sectional sample of nine children with LH injury included in Study 1b are shown[ The age at test is listed in the upper left corner[ The assigned category score"s# is indicated at the lower left[
was classi_ed as a reduction[ At 8!1 there was some distortion of the central area of the house\ but the overall shape was consistent with his house formula[ M[G[|s last four attempts\ at 8!8\ 00!9\ 01!1\ and 02!0\ each showed some deviation from the canonical representation of a house[ However\ close inspection shows that for each drawing the core form remained in tact\ and the devi! ations consisted of elements added around the basic house[ Indeed\ at 00!9\ one of the impossible features is the safe "attached to the right side of the house# which contains a million dollars[ At 02!0\ solar panels have been added around the roof[
J[D[ _rst attempted impossible houses at age 5!9[ The house was classi_ed an a object conversion[ The child drew her basic house and then added a face and wings[ She used a similar strategy at 8!7[ At 5!5 she stacked a series of squares thus achieving a distortion of the whole[ At 6!9 she drew a scribble\ with a cloud above and said that the clouds had crushed the house[ At 00!0 she used a rotation strategy[ E[M[|s _rst attempt at an impossible house at 5!0 was a tiny closed form at the bottom of the page that was classi_ed as a reduction[ In her second attempt at age 6! 7\ she produced a house nearly identical to her canonical
297
J[ Stiles et al[:The development of drawing in children with congenital focal brain injury
Fig[ 4[ The impossible house drawings from the cross!sectional sample of nine children with RH injury included in Study 1b are shown[ The age at test is listed in the upper left corner[ The assigned category score"s# is indicated at the lower left[
representation\ but with an added chimney[ When asked why the house was impossible she used a verbal strategy\ {{because in the kitchen everything is _re\ it|s hot so you can|t touch it||[ In her attempt at drawing an impossible house at age 7!7\ she added a mouth and arms thus using an object conversion strategy[ At 09!5 she was scored as using a deletion and an atypical placement strategy[ She crossed out the places for windows and doors\ and said you could not get to it[ R[D[ used a reduction strategy for his _rst and second impossible houses at ages 8!3 and 09!2[ At 00!2 he drew three houses\ and reported that one had windows that
were too large\ one had windows that were too small and the third house was so small nobody could live in it[ Thus\ although he was scored as using both a reduction and a part distortion strategy\ the distortion involved changing the size of the parts[
General discussion All of the children with focal brain injury presented in this study showed notable and continuous improvement in their graphic representation of {possible| houses[ Over
J[ Stiles et al[:The development of drawing in children with congenital focal brain injury
298
Fig[ 5[ The longitudinal series of impossible house drawings for six children with LH injury are shown[
time the houses became more complex\ incorporating more features and more complex sets of spatial structures[ For example\ by the late school age period\ many of the children attempted to represent three!dimensionality in their drawings[ However\ the consistency of the children|s depictions over time is also striking[ Consistent with earl! ier literature\ it appears that the children did indeed
develop formulaic graphic expressions for representing houses[ Thus\ in the series presented here\ we see the emergence and the elaboration of graphic formulas in all of the children tested[ The graphic formula appears to be a useful and e.cient strategy for representing objects\ here houses\ symbolically[ It is particularly notable that even those children with RH injury with documented
209
J[ Stiles et al[:The development of drawing in children with congenital focal brain injury
Fig[ 6[ The longitudinal series of impossible house drawings for six children with RH injury are shown[
di.culty in early graphic production "i[e[ P[K[\ M[B[\ J[D[\ E[M[# were able to develop graphic formulas which accurately portrayed houses[ The question asked at the beginning of this study was how do children who show such marked impairment early in development improve so dramatically< One possible answer is that their improvement was due to some general
underlying recovery of their spatial analytic skills[ By this account\ the children should have become pro_cient in drawing gradually\ and eventually reach a level of per! formance that was indistinguishable from other children[ An alternative possibility is that the task of gradually building a repertoire of formulas served compensatory strategy which allowed for a much more limited form of
J[ Stiles et al[:The development of drawing in children with congenital focal brain injury
improvement[ By this account performance would improve such that the drawing of particular graphic objects would gradually become indistinguishable from those of other children\ but the range and ~exibility of the children|s drawings would be more limited[ Under these conditions\ children with RH injury would be much more reliant on these formulaic expressions than children without such de_cits[ The data from the impossible _g! ures task supports the later account[ The results of this study showed that children with RH injury did not produce new or novel graphic forms with new and unusual organization properties[ They did not alter the spatial structures of their drawing formulas[ The most common strategies were reduction\ rotation and object conversion[ None of these strategies required the child to generate an alternative spatial con_guration\ and thus did not require the child to re!analyze the spatial properties of the target form[ In several cases the children used rotation\ which clearly has a spatial component[ However in executing the drawings\ the children rotated their arms and heads\ and thus generated the drawing from a canonical perspective[ It might be argued that the present task did not speci_cally instruct the child to alter the structure of the house\ and that the children might have used distortion strategies with greater frequency if explicitly asked to do so[ While this is a possibility that should be tested\ the resistance to spatial distortion stra! tegies among children with RH injury in the present stud! ies is striking[ Over periods of three to _ve years\ spanning the school age period the absence of distortion strategies is notable\ and contrasts markedly with the performance of children with LH injury[ It should also be noted that this failure to deviate from preexisting graphic formulas did not mean that the children lacked imaginative ~exibility\ or that they failed to understand the task[ Indeed they came up with many very creative solutions for this rather unusual task[ In all but a few cases the children|s solution to the problem of making an impossible house fell with the range of stra! tegies used by normally developing children[ What was unusual among children with RH injury was the dis! tribution of strategies\ and speci_cally\ their extremely limited use of what is the dominant strategy among nor! mal children\ con_gural distortion[ In summary\ the children with RH injury reported in this study showed clear evidence of development and apparent recovery of spatial ability on a free drawing task in which they were simply asked to draw a house[ In contrast to their performance early in development ð18Ł\ the children produced organized and well!integrated forms[ This could be interpreted as representing an initial\ brief period of developmental delay followed by recovery[ However\ the children|s performance on the impossible _gures task suggests an alternative explanation[ Those data suggest that rather than general recovery of basic spatial integrative skills\ the children with RH injury\ like the other children in the study\ appear to have acquired a repertoire of graphic formulas[ These formulas allowed
200
the children to perform at the level of their peers in the free drawing task[ However\ the children with RH injury appear to rely upon these formulas more than normal children or children with LH injury[ This reliance on formulaic drawing strategies became evident within the context of the impossible _gures task[ While all of the children with RH injury successfully solved the problem of producing an {impossible| house\ they rarely used the strategy that is adopted most frequently by normal chil! dren and children with LH injury\ con_gural distortion[ Thus\ the children with RH injury were able to solve the problem of impossibility\ but they did not use strategies that involve spatial reorganization[ In this sense\ the chil! dren are limited in the ~exibility of their graphic expression[ It is this lack of ~exibility with the structure of formula itself that suggests a persistent di.culty in their ability to reorganize and reformulate the spatial structure of the graphic object[ If this is the case then\ while the children are clearly demonstrating functional recovery in their acquisition of graphic formulas\ the degree of recovery may be more restricted than the data _rst suggest[
References 0[ Alajouanine\ T[ and Lhermitte\ F[ Acquired aphasia in children[ Brain 77\ 442Ð451\ 0854[ 1[ Aram\ D[ M[\ Ekelman\ B[ L[\ Rose\ D[ F[ and Whi! taker\ H[ A[ Verbal and cognitive sequelae following unilateral lesions acquired in early childhood[ Jour! nal of Clinical and Experimental Neuropsycholo`y 6\ 44Ð67\ 0874[ 2[ Aram\ D[ M[\ Ekelman\ B[ L[ and Whitaker\ H[ A[ Spoken syntax in children with acquired unilateral hemisphere lesions[ Brain and Lan`ua`e 16\ 64Ð099\ 0875[ 3[ Aram\ D[ M[\ Rose\ D[ F[\ Rekate\ H[ L[ and Whitaker\ H[ A[ Acquired capsular:striatal aphasia in childhood[ Archives of Neurolo`y 39\ 503Ð506\ 0872[ 4[ Brown\ J[ W[ and Ja}e\ J[ Hypothesis on cerebral dominance[ Neuropsycholo`ia 02"0#\ 096Ð009\ 0864[ 5[ Carlson\ J[\ Netley\ C[\ Hendrick\ E[ and Pritchard\ J[ A reexamination of intellectual abilities in hemi! decorticated patients[ Transactions of the American Neurolo`ical Association 82\ 087Ð190\ 0857[ 6[ Day\ P[ S[ and Ulatowska\ H[ K[ Perceptual\ cogni! tive\ and linguistic development after early hemi! spherectomy] Two case studies[ Brain and Lan`ua`e 6\ 06Ð22\ 0868[ 7[ Fenson\ L[ The transition from construction to sket! ching in children|s drawings[ In Visual Order] The Nature and Development of Pictorial Representation\ N[H[ Freeman and M[V[ Cox "Editors#\ pp[ 263Ð273[ Cambridge\ New York\ 0874[ 8[ Freeman\ N[ H[ Strate`ies of Representation in Youn` Children] Analysis of Spatial Skills and Drawin` Pro! cesses[ Academic Press\ New York\ 0879[
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09[ Goodnow\ J[ J[ Children|s Drawin`s[ Open\ London\ 0866[ 00[ Gott\ P[ S[ Cognitive abilities following right and left hemispherectomy[ Cortex 8\ 155Ð163\ 0862[ 01[ Gridley\ P[ F[ Graphic!representation of a man by four!year!old children in nine prescribed drawing situations[ Genetic Psycholo`y Mono`raphs 19\ 072Ð 249\ 0827[ 02[ Hammill\ D[ and Irwin\ O[ C[ I[Q[ di}erences of right and left spastic hemiplegic children[ Perceptual and Motor Skills 11\ 082Ð083\ 0855[ 03[ Karmilo}!Smith\ A[ Constraints on representational change] Evidence from children|s drawing[ Co`nition 23\ 46Ð72\ 0889[ 04[ Krashen\ S[ D[ Lateralization\ language learning\ and the critical period] Some new evidence[ Lan`ua`e Learnin` 12"0#\ 52Ð64\ 0862[ 05[ Lenneberg\ E[ The Biolo`ical Foundations of Lan`! ua`e[ Wiley\ New York\ 0856[ 06[ Markham\ S[ An item analysis of children|s drawings of a house[ Journal of Clinical Psycholo`y 09\ 074Ð 076\ 0843[ 07[ Mc_e\ J[ The e}ects of hemispherectomy on intel! lectual functioning in cases of infantile hemiplegia[ Journal of Neurolo`y\ Neurosur`ery\ and Psychiatry 13\ 139Ð138\ 0850[ 08[ Reed\ J[ C[ and Reitan\ R[ M[ Verbal and per! formance di}erences among brain!injured children with lateralized motor de_cits[ Neuropsycholo`ia 8\ 390\ 0860[ 19[ Rudel\ R[ G[ and Teuber\ H[ L[ Spatial orientation in normal children and in children with early brain damage[ Neuropsycholo`ia 8\ 390Ð396\ 0860[ 10[ Rudel\ R[ G[\ Teuber\ H[ L[ and Twitchell\ T[ Levels of impairment of sensorimotor function in children with early brain damage[ Neuropsycholo`ia 01\ 84Ð 097\ 0863[ 11[ Stiles\ J[\ Stern\ C[\ Trauner\ D[ and Nass\ R[ Devel! opmental change in spacial grouping activity among children with early focal brain injury] Evidence from a modeling task[ Brain and Co`nition\ 23\ 35Ð51 "0885#[ 12[ Stiles\ J[ The early use of graphic formulas] Case study reports of graphic formula production by 1! to 2!year!old children[ International Journal of Devel! opmental Psycholo`y\ 016Ð038\ 0884[
13[ Stiles\ J[ Plasticity and development] Evidence from children with early occurring focal brain injury[ In Maturational Windows and Adult Cortical Plasticity\ B[ Julesz and I[ Kovacs "Editors#\ Vol[ XXIV[ Addison!Wesley\ Santa Fe\ CA\ 0884[[ 14[ Stiles\ J[ and Thal\ D[ Linguistic and spatial cognitive development following early focal brain injury] Pat! terns of de_cit and recovery[ In Brain Development and Co`nition\ M[ Johnson "Editor#\ pp[ 533Ð553[ Blackwell\ Cambridge\ MA\ 0882[ 15[ Stiles\ J[ and Nass\ R[ Spatial grouping activity in young children with congenital right or left hemi! sphere brain injury[ Brain and Co`nition 04\ 190Ð111\ 0880[ 16[ Stiles!Davis\ J[\ Sugarman\ S[ and Nass\ R[ The development of spatial and class relations in four young children with right cerebral hemisphere dam! age] Evidence for early spatial!constructive de_cit[ Brain and Co`nition 3\ 277Ð301\ 0874[ 17[ Stiles!Davis\ J[ Spatial dysfunction in young children with right cerebral hemisphere injury[ In Spatial Co`! nition] Brain Bases and Development\ J[ Stiles!Davis\ M[ Kritchevsky\ and U[ Bellugi "Editor#[ Lawrence Erlbaum\ Hillsdale\ N[J[\ 0877[ 18[ Stiles!Davis\ Janowsky\ J[\ Engel\ M[ and Nass\ R[ Drawing ability in four young children with con! genital unilateral brain lesions[ Neuropsycholo`ia 15\ 248Ð260\ 0877[ 29[ Swindell\ C[ S[\ Hoolland\ A[ L[\ Fromm\ D[ and Greenhouse\ J[ B[ Characteristics of recovery of drawing ability in left and right brain!damaged pat! ients[ Brain and Co`nition 6\ 05Ð29\ 0877[ 20[ Thomas\ G[V[\ and Silk\ A[M[ "0889#[ An Intro! duction to the Psycholo`y of Children|s Drawin`s[ Harvester Wheatsheaf\ New York[[ 21[ van Sommers\ P[ Drawin` and Co`nition] Descriptive and Experimental Studies of Graphic Production Pro! cesses[ Cambridge University Press\ New York\ 0873[ 22[ Vargha!Khadem\ F[\ O|Gorman\ A[ and Watters\ G[ Aphasia and handedness in relation to hemispheric sides\ age at injury and severity of cerebral lesion during childhood[ Brain 097\ 556Ð585\ 0874[ 23[ Stiles\ J[\ Delis\ D[ C[ and Tada\ W[ L[ GlobalÐlocal processing in preschool children[ Child Development 51\ 0147Ð0164\ 0880[
Pergamon
PII] S9917Ð2821"85#99977Ð6
Neuropsycholo`ia\ Vol[ 24\ No[ 2\ pp[ 188Ð201\ 0886 Þ 0886 Elsevier Science Ltd[ All rights reserved Printed in Great Britain 9917Ð2821:86 ,06[99¦9[99
The development of drawing in children with congenital focal brain injury] Evidence for limited functional recovery JOAN STILES\ DORIS TRAUNER\ MURRAY ENGEL$ and RUTH NASS% Department of Cognitive Science\ University of California\ 8499 Gilman Drive\ La Jolla\ CA 91982!9098\ U[S[A[^ $New York Hospital\ Cornell Medical Center\ New York\ U[S[A[^ %New York University Medical Center\ New York\ U[S[A[ "Received 11 November 0882^ accepted 01 July 0885#
Abstract*Children with pre! or perinatal injury to right hemisphere "RH# brain regions show impairment of spatial integrative functions similar to that observed among adults with comparable injury[ Unlike adults\ children show considerable improvement with development on a range of spatial construction tasks which require spatial integration[ Such gains could re~ect true recovery of spatial integrative abilities[ Alternatively\ the improvement could be more limited in scope\ re~ecting the development of compensatory strategies which are task speci_c and allow the children to circumvent\ rather than overcome\ their primary spatial disorders[ The studies presented here examined this distinction within the context of drawing tasks in which the child was _rst asked to draw a house and then an impossible house[ The impossible house task was designed to examine the extent to which children rely on graphic formulas in generating organized drawings[ The results showed that while all of the children with RH injury make considerable progress in free drawing into the school age period\ they are very reliant on the use of graphic formulas[ When given a task which requires them to alter their drawings\ they did not change the spatial con_guration of the depicted object[ Rather they found alternate ways to render the object {impossible|[ Þ 0886 Elsevier Science Ltd[ All rights reserved[ Key Words] plasticity^ brain injury^ drawing[
ever\ little is known about the developmental course or process of functional recovery in the child population[ The assessment of functional recovery from a behavioral perspective must take account of the process as well as the product of behavior[ Similar outcomes may be achieved in di}erent ways[ Thus\ when mastery is observed it is important to document whether it was achieved[ The present study is a _rst attempt to focus on this aspect of recovery by examining improvement on a drawing task among children with RH injury[ The spatial integrative de_cits of preschool children with RH injury have been particularly striking on free drawing tasks[ In an earlier study ð18Ł\ we reported data from a drawing task involving two young children with RH injury[ The children were 4 years old when the draw! ings were produced\ and each showed marked de_cits of spatial integration[ Speci_cally\ in their drawings of houses and people\ the children included appropriate parts but failed to arrange those parts into spatially inte! grated whole forms[ The parts were scattered around the page or strung together in random arrays[ These kinds of spatial integrative de_cits were not observed in age and
Introduction Early focal brain injury results in subtle but speci_c forms of spatial cognitive de_cit ð13Ð18Ł[ Speci_cally\ children with right hemisphere "RH# injury have di.culty with spatial integration[ While they can identify and segment the parts of spatial forms\ they are impaired in their ability to organize those parts into well!formed spatial con_gurations[ By contrast\ children with left hemisphere injury "LH# are impaired in their ability to process pattern detail[ The de_cits observed in children are consistent with the patterns of de_cit observed among adults with similar injuries[ However\ impairment in the child popu! lation is generally milder than that of adults\ and pre! liminary data suggest that children are better able to compensate for their de_cits than adults[ The observation that children are better able to com! pensate for cognitive or linguistic de_cits is not new "e[g[ ð0Ð6\ 00\ 02\ 04\ 05\ 07Ð10\ 22Ł[ Many\ primarily retro! spective\ accounts of behavioral functioning following early focal brain injury converge on the view that capacity for recovery is greater among children than adults[ How! 188
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J[ Stiles et al[:The development of drawing in children with congenital focal brain injury
IQ matched children with LH injury whose performances were comparable to that of normal 4!year!olds[ The drawing anomolies observed in the children with RH injury are consistent with those reported by Swindell and colleagues ð29Ł for adult patients[ These authors describe their patients| drawings as {{scattered\ fragmented\ and disorganized|| "p[ 08#[ We have collected a considerable body of drawing data since our original _ndings were reported[ Among the longitudinal data obtained were drawings of houses[ These data are the focus of the current studies[ Across the series of three studies\ we examined change in both the children|s free drawing of houses and in their responses to a probe question designed to elicit an alternative ren! dering of houses[ The _rst measure was designed to assess mastery on a speci_c task\ while the second examined ~exibility or reliance on speci_c drawing strategies[ Study 0 was a longitudinal study of house drawing[ It was designed to determine whether the children|s drawings would improve with development\ and whether there would be consistency over time in the way houses were depicted[ Study 1 was a cross!sectional study in which performance on the house drawing task was compared to performance on a task in which children were asked to draw a house that was di}erent from their usual one[ This study provided data from both a large sample of normally developing children on the elicited task\ and a cross!sectional sample comparing performance of the lesion groups with normal controls on the free and elicited drawing tasks[ Study 2 provided longitudinal data on performance on the elicited task[
Descriptions of subjects The three studies described in this report present data from many of the same subjects[ For brevity\ a single subject description section providing information on all subjects included in the three studies is included here[ All the children in the brain injured groups sustained unilateral focal injury either prenatally or during the _rst six months of life\ as documented by a CT or MRI scan[ Children were excluded from the study if they dem! onstrated evidence of multiple lesions\ di}use damage or conditions which may have caused global brain damage\ such as a viral infection\ encephalitis\ or anoxia[ Table 0 provides descriptions of all of the children with RH or LH injury participating in the current series of studies[
Study 0] Longitudinal data from a house drawing task The purpose of this study was to document devel! opmental change in performance on a free drawing task among children with unilateral focal brain injury[ Our earlier study ð18Ł indicated that at 4!years of age children with RH but not LH injury have di.culty in drawing simple objects[ In this study we examine performance on
this task through the school!age period[ Longitudinal series of house drawings collected in a free drawing task are presented for 5 children with RH injury\ 5 with LH injury and 5 controls matched for age and IQ[ We selected children for whom we had a minimum of four data points spanning at least a 1!year period[
Longitudinal series of house drawings] Children with early LH injury Figure 0 shows the longitudinal series of drawings from children with LH injury[ The houses have an outer boundary\ and the parts are clearly depicted and appro! priately arranged within the house boundaries[ Although the drawings improve with age there is also a notable similarity in the drawings of individual children over time[ Consistent with studies of adults and normally developing children ð7Ð09\ 01\ 03\ 06\ 12\ 20\ 21Ł\ the children in this study appear to have developed graphic formulas for house drawing[ These formulas underwent modi_cation over time "note\ for example\ the intro! duction of 2!dimensional representation in several of the children|s drawings# but the similarity of drawings from one session to the next is evident[
Longitudinal series of house drawings] Children with early RH injury Figure 1 shows the house drawings produced by chil! dren with RH injury[ Consistent with our earlier study ð18Ł young children with RH injury initially had di.culty producing organized representations[ However\ with time\ considerable improvement was noted[ By age 5 or 6\ all of the children were able to generate organized and integrated drawings of houses[ Like the normal children and children with LH injury\ consistency across time in the way houses were depicted was also evident[ Thus despite initial di.culty on this task\ children with RH injury appear to have developed strategies for drawing simple pictures of houses\ very likely through the devel! opment of graphic formulas[ These data point to signi_cant functional improvement for the children with RH injury on this speci_c drawing task[ Their drawings improved markedly\ and that improvement persisted over time[ However\ to under! stand the phenomena of functional recovery it is necess! ary to assess not just whether a child has improved on a task or set of tasks\ but where possible to ask how the child has achieved that measure of success[ Children may be able to compensate on a speci_c task without actually overcoming the de_cit\ per se[ One possible marker of subtle persistent de_cit is the extent to which a child relies on a speci_c compensatory strategy[ That is\ is the child|s successful performance bound to a particular narrowly de_ned strategy or can the child deal more ~exibly with the spatial problem solving situation< Tasks which
J[ Stiles et al[:The development of drawing in children with congenital focal brain injury
290
Table 0[ Summary of the neurological\ IQ and age data for children with early right or left unilateral focal brain injury
Subject Sex
Lesion Site
Lesion Onset
Seizures
IQ
Right Hemisphere prenatal
no
perinatal
yes
WISC III V094 P66 F89 WISC III V82 P53 F66 WISC!R V092 P091 F091 WISC!R V024 P095 F012 WISC III V65 P61 F61 WISC III V008 P66 F87 WISC III V62 P68 F62 WISC!R V007 P004 F008 WISC!R V79 P001 F83
MB
M
NS
M
frontal parietal*cortical and subcortical frontal*cortical and subcortical
MG
M
parietal*subcortical only
pre! or perinatal
no
RD
M
perinatal
no
PK
M
prenatal
yes
AP
M
prenatal
no
EM
F
frontal parietal temporal*cortical and subcortical frontal parietal temporal*cortical and subcortical parietal temporal*cortical and subcortical parietal*subcortical only
perinatal
no
JD
F
parietal temporal*subcortical only
peri
no
RH
M
frontal*cortical and subcortical
pre! or perinatal
no
PA
F
Left Hemisphere pre! or perinatal<
no
JP
M
perinatal
no
AG
M
parietal temporal occipital*cortical and subcortical frontal parietal temporal*cortical and subcortical frontal*subcortical only
perinatal
no
GC
M
temporal*cortical and subcortical
perinatal
no
DV
F
prenatal
yes
KQ
M
perinatal
no
NP
F
frontal parietal temporal*cortical and subcortical frontal parietal temporal*cortical and subcortical temporal*cortical only
pre! or perinatal<
no
SB
M
partietal*subcortical only
prenatal
no
JQ
F
parietal temporal occipital*cortical and subcortical
pre! or perinatal<
yes
WISC!R V092 P67 F89 WISC R V68 P73 F79 WISC!R V096 P012 F005 WISC!R V095 P094 F094 WISC!R V80 P89 F89 WISC!R V094 P85 F090 WISC!R V095 P84 F090 WISC!R V012 P005 F011 WISC!III V009 P004 F002
Subject] Studies 0 and 2
Age at Test "yr!mo#] Study 1
yes
6Ð00
no
7Ð4
yes
8Ð1
yes
8Ð3
yes
8Ð6
no
09Ð9
yes
09Ð5
yes
00Ð0
no
02Ð2
no
6Ð1
no
7Ð0
yes
7Ð0
yes
7Ð1
yes
8Ð09
yes
09Ð9
no
09Ð2
yes
09Ð09
yes
04Ð3
In some cases it is unclear whether the onset of the stroke was in the pre! or perinatal period[ These are noted as {pre! or perinatal<|
require the children to use strategies other than the ones they typically employ\ can reveal a great deal about the facility with which children can solve spatial problems[ Excessive reliance on a single strategy can be a marker of residual de_cit[ Study 1 was designed to explore these issues[
Study 1] Cross!sectional data from the {impossible house| task One notable feature of the drawing series for each of subjects in Study 0 was the consistency of the drawings over time[ Drawings produced over a period of years maintained a marked similarity[ One interpretation of this consistency is that the children develop graphic for!
mulas for drawing common objects such as houses[ The use of graphic formulas is a common and well!docu! mented drawing strategy among normal adults and chil! dren ð7Ð09\ 01\ 03\ 06\ 12\ 20\ 21Ł[ Graphic formulas are de_ned as the procedure or set of implicit rules by which a graphic object is produced[ The hallmark of the graphic formula is the relative inaccessibility of the production procedures which underlies it ð03Ł[ Consider\ for example\ the production of a 4!pointed star[ Although the initial learning of the form may have been quite painstaking\ it constitutes a graphic formula for most adults[ A typical reproduction sequence begins at one vertex "usually the same vertex for a given individual# and the _ve lines comprising the _gure are generated in turn[ The formulaic nature of this graphic production can be conveyed by asking that the drawer begin from any vertex other than
291
J[ Stiles et al[:The development of drawing in children with congenital focal brain injury
Fig[ 0[ The longitudinal series of house drawings are presented for six children with LH injury[ Note the consistency over test session in the shape and organization of the drawing[
the usual starting point[ This exercise generally results in an initial delay as the drawer attempts to make explicit the usually implicit set of rules for drawing the form[ From the earliest stages of drawing development\ at about age 1\ normal children produce graphic formulas ð12Ł[ Once mastered\ graphic formulas o}er a means of simplifying the problem of graphic representation by eli! minating the requirement to analyze the spatial properties
of the form to be represented[ Thus\ they o}er a poten! tially useful compensatory strategy for children with speci_c spatial analytic de_cits[ It is possible that the improvement observed in the free drawings of children with RH injury involves the gradual mastery of a core set of graphic formulas\ rather than more general improvement in spatial analytic abilities[ If this is the case then\ while the children clearly demonstrate functional
J[ Stiles et al[:The development of drawing in children with congenital focal brain injury
292
Fig[ 1[ The longitudinal series of house drawings are presented for six children with RH injury[ For those children tested in the late preschool period "P[K[\ M[B[\ J[D[ and R[D[# the initial disorganization of the drawing is evident[ In each case the drawings improve with development[ Note the consistency of the drawing across testing sessions[
recovery\ the degree of recovery may be more restricted than the data _rst suggest[ In Study 1\ we used a drawing task adapted from one developed by Karmilo}!Smith ð03Ł in a study of normally developing 4! to 09!year!old children[ In this task\ the child _rst draws a picture of a house\ and is then asked to draw {{an impossible house\ a house that couldn|t possibly be\ a make!believe house||[ The normally developing children in Karmilo}!Smith|s study produced a range of fanciful responses to this request\ many of
which involved spatial recon_guration[ If the mastery of house drawing observed among children with RH injury depends on the use of a graphic formula\ and does not re~ect a more general improvement in their spatial ana! lytic abilities\ then their performance on the {impossible house| task should di}er systematically from that of nor! mal controls and children with LH injury[ The primary di}erences should lie in the types of strategies they use to generate impossible houses[ Speci_cally\ children with RH injury should show limited use of strategies which
293
J[ Stiles et al[:The development of drawing in children with congenital focal brain injury
involve re!analysis of the spatial array[ Rather than adopting strategies involving con_gural distortion of the parts and wholes of an array\ the children should use strategies that allow them to retain the con_gural organ! ization of their graphic formulas but still render the house impossible[
Study 1a] Cross!sectional data from normally developing children Karmilo}!Smith ð03Ł described a range of drawing strategies used by normally developing 4! to 09!year!olds on the impossible drawing task[ As indicated in Study 0\ the children with RH injury still exhibited considerable di.culty in simple house drawing at age 4\ thus we did not begin to collect data from the more di.cult imposs! ible house task until age 5 to 6\ and we continued data collection beyond age 09[ For this reason\ we collected a separate sample of data from 004 normally developing children in the 5! to 04!year age range\ and we examined the type and distribution strategies they used to create impossible houses[ Study 1a presents those data[
Method Subjects The sample for this study included 009 children between 5! and 04!years of age[ A total of 44 children constituted a younger group that ranged in age from 5!years "5!9# to 7!years and 00! months "7!00#\ and 59 children constituted the older group that ranged from 8!9 to 04!9[ The children were tested in a variety of school and laboratory settings[
Scoring Each drawing was scored according to the drawing strategy or strategies used to produce an impossible house[ The scoring system was adapted from Karmilo}!Smith\ and consisted of the following eight categories] 0[ Con_`ural distortions including "a# scrambling the parts\ "b# distortion of the outer form and "c# distortion of the parts[ 1[ Rotation[ 2[ Part deletion "a# or repetition "b#[ 3[ Reduction[ 4[ Object transformation which involved either turning a second object into a house by adding doors and windows\ or turning a house into something else by adding atypical features such as facial features[ 5[ Object substitution which involved the simple replacement of one object for another without transformation[ 6[ Placement in an atypical location such as on the moon or under the earth[ 7[ Verbal description which involved production of a typical house accompanied with a description of why the house was impossible[ Typical examples of each of these categories drawn from the
sample of normally developing children are shown in Fig[ 2[ It was possible for a child to include more than one strategy in his:her drawing[ For example\ a child could distort the overall con_guration and turn it upside!down[ In scoring\ each drawing was assigned all appropriate category scores[ All 004 drawings could be assigned to at least one of the eight categories[ The drawings were scored by a single rater[ To assess reliability\ 14) of the drawings were scored by a second rater[ Scoring reliability was 099)[
Results and discussion The purpose of this study was to determine the fre! quencies with which normally developing children use the strategies originally described by Karmilo}!Smith as typical responses to the instruction to draw an impossible house[ Table 1 shows the frequency distributions across the eight categories for the full sample\ and the dis! tributions for the younger and older groups separately[ Note that because some children used more than one strategy in their drawing\ the percentages within each distribution sum to more than 099)[ Thus the data re~ect the percentage of children who used a strategy\ rather than the proportional use of strategies across the group[ Within the full sample\ 81 drawings were assigned to a single category\ 11 were assigned to two categories and 0 was assigned to three categories[ It is evident from the table that the predominant strategy among normally developing children involved con_gural distortion of the parts\ the whole or the relation between the parts and the whole[ In over half the cases "20 of 46# con_gural distortions involved some combination of part distortion\ whole\ distortion and scrambling[ There were only _ve cases in which only the parts were distorted[ The remain! ing seven strategies were all used regularly\ though less frequently\ by normally developing children\ and all were clearly viable strategies for rendering a house {imposs! ible|[ Nonetheless\ they were nondominant strategies[ Finally\ note that the distribution of strategy use among older and young children was very similar[
Study 1b] Cross!sectional data from children with early focal brain injury This study examined the performance of a cross!sec! tional sample of children with unilateral focal brain injury on the {impossible houses| task[ The purpose was to examine all the possible strategies used by the di}erent groups in solving the problem of graphically depicting an impossible house[
Method Subjects This study focused on a cross!sectional sample of children with unilateral focal brain injury in the 6! to 04!year age range[
J[ Stiles et al[:The development of drawing in children with congenital focal brain injury
294
Fig[ 2[ All of the impossible house drawings were scored as representing eight categories[ An example of a typical drawing from each category is shown[ These examples were drawn from the cross!sectional sample of 004 normally developing children included in Study 1a[ Note that a drawing could be assigned to more than one category score[
All of the children listed in Table 0 were included in this sample[ There were nine children in each group[ The age at test for each child is indicated in the table[ The two lesion groups were comparable in age "M 8!00 for the RH and 8!7 for the LH group# with the following IQ means] VIQ] PIQ] FSIQ]
LH 092[2 LH 099 LH 091
RH 099[11 RH 78[2 RH 83[1
In addition\ a group of 01 normally developing controls of comparable age "M 8!4# and FSIQ "M 009#\ VIQ "M 001[56# and PIQ"M 095# were included in the analyses[
Procedure Each child was asked to draw a house\ and then an impossible house[ Drawings were scored according to the system described in Study 1a\ above[
Results and discussion Study 1a indicated that the most common strategy for creating an impossible house among normally developing
295
J[ Stiles et al[:The development of drawing in children with congenital focal brain injury Table 1[ Distribution of category usage by 004 normal 5! to 04!year!old children
Category 0 Con_g[ Dist[ Scramble Whole Part 1 Rotation 2 Part Del:Rep 3 Reduction 4 Object Conv[ 5 Form[ Sub[ 6 Placement 7 Verbal
All Children "n 004# Percent of Number of uses drawings 46 06 30 20 01 07 00 04 4 07 3
Ages 5Ð7\ 00 "n 44# Percent of Number of uses drawings
38[5
09[3 04[6 8[5 02 3[2 04[6 2[4
children was distortion of the spatial con_guration[ It was predicted that children with RH injury would have di.culty using this strategy because it requires re!analysis of the spatial array[ Chi squared analysis was used to examine the frequency of usage of the con_gural dis! tortion strategy "Category 0# versus the other seven stra! tegies[ The results of the analysis showed signi_cant di}erences between the groups[ The RH group used the con_gural distortion strategy signi_cantly less often than normally developing children or children with LH injury\ X1 7[06\ P³9[94[ Figures 3 and 4 show the possible and impossible drawings of the children with LH and RH injury\ respectively[ The subject|s initials and age at test is noted at the top left of each child|s possible house drawing^ the strategy category "0Ð6\ see above# is noted at the bottom left of the impossible drawing[ The draw! ings of the LH children were indistinguishable from those of children in the normally developing group in terms of type and distribution of strategies[ Note that the children with RH injury generally used strategies that are typical of normally developing children\ but they di}ered in the distribution of strategies used[ Speci_cally\ only one of the children with RH injury "M[G[# used con_gural dis! tortion[ In addition\ one of the children|s drawings "E[M[# did not _t easily into any of the strategy categories[
Study 2] Longitudinal data from the {impossible house| task Study 2 was intended as an expansion of the _ndings from Study 1b[ This study focused on the longitudinal series of {impossible house| drawings from the same six children with RH injury whose free drawings were pre! sented in Study 0[ One data point from each of these children was included in the analysis from Study 1b[ The purpose of this study was to provide a more extensive body of data on the performance of children with RH injury\ and to demonstrate the persistence of their failure to use con_gural strategies on this task[ For complete! ness\ {impossible house| data from the six children with
13 5 10 01 2 8 5 8 0 09 1
32[5
4[4 05[3 09[8 05[3 0[7 07[1 2[5
Ages 8Ð04 "n 59# Percent of Number of uses drawings 22 00 19 08 8 8 4 5 3 7 1
44
04 04 7[2 09 5[6 02[2 2[2
LH injury included in Study 0 are presented brie~y at the beginning of this section[
Longitudinal series of {impossible house| drawings] Children with early LH injury Figure 5 shows the longitudinal series of {impossible house| drawings from six children with LH injury[ The range of strategies used in these series approximated those found among the large cross!sectional sample of normally developing children reported in Study 1a[
Longitudinal series of {impossible house| drawings] Children with early RH injury The impossible house drawings of six children with RH injury are shown in Fig[ 6[ P[K[ was _rst asked to draw an impossible house at age 8!0[ At ages 8!0\ 8!6 and 09!0\ he used the object substitution strategy[ At ages 00!0 and 01!1\ P[K[ used the atypical location strategy\ placing the house on a cloud\ a roof and Mars\ re! spectively[ At 00!6 he said that the house was impos! sible because it is impossible for someone to _t under the roof[ At 4!09 M[B[ was asked for the _rst time to draw an impossible house[ His response was to draw a ~ower\ which was scored as a object substitution response[ Object substitution is a very infrequent response among normal children[ Yet it is one that M[B[ used three time in this series[ Two other strategies were evident in M[B[|s drawings[ At age 5!3\ when asked to draw an impossible house\ he gleefully returned the blank paper to the exper! imenter and announced he had drawn an invisible house[ When pressed to draw something\ he produced an object substitution[ He drew a person and labeled it a house[ At 6!00 M[B[ used a rotation strategy which persisted to the next session[ In the _nal session he used a reduction strategy[ He attached two little houses to the big one[ M[G[|s _rst attempt at an impossible house at age 7!9
J[ Stiles et al[:The development of drawing in children with congenital focal brain injury
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Fig[ 3[ The impossible house drawings from the cross!sectional sample of nine children with LH injury included in Study 1b are shown[ The age at test is listed in the upper left corner[ The assigned category score"s# is indicated at the lower left[
was classi_ed as a reduction[ At 8!1 there was some distortion of the central area of the house\ but the overall shape was consistent with his house formula[ M[G[|s last four attempts\ at 8!8\ 00!9\ 01!1\ and 02!0\ each showed some deviation from the canonical representation of a house[ However\ close inspection shows that for each drawing the core form remained in tact\ and the devi! ations consisted of elements added around the basic house[ Indeed\ at 00!9\ one of the impossible features is the safe "attached to the right side of the house# which contains a million dollars[ At 02!0\ solar panels have been added around the roof[
J[D[ _rst attempted impossible houses at age 5!9[ The house was classi_ed an a object conversion[ The child drew her basic house and then added a face and wings[ She used a similar strategy at 8!7[ At 5!5 she stacked a series of squares thus achieving a distortion of the whole[ At 6!9 she drew a scribble\ with a cloud above and said that the clouds had crushed the house[ At 00!0 she used a rotation strategy[ E[M[|s _rst attempt at an impossible house at 5!0 was a tiny closed form at the bottom of the page that was classi_ed as a reduction[ In her second attempt at age 6! 7\ she produced a house nearly identical to her canonical
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J[ Stiles et al[:The development of drawing in children with congenital focal brain injury
Fig[ 4[ The impossible house drawings from the cross!sectional sample of nine children with RH injury included in Study 1b are shown[ The age at test is listed in the upper left corner[ The assigned category score"s# is indicated at the lower left[
representation\ but with an added chimney[ When asked why the house was impossible she used a verbal strategy\ {{because in the kitchen everything is _re\ it|s hot so you can|t touch it||[ In her attempt at drawing an impossible house at age 7!7\ she added a mouth and arms thus using an object conversion strategy[ At 09!5 she was scored as using a deletion and an atypical placement strategy[ She crossed out the places for windows and doors\ and said you could not get to it[ R[D[ used a reduction strategy for his _rst and second impossible houses at ages 8!3 and 09!2[ At 00!2 he drew three houses\ and reported that one had windows that
were too large\ one had windows that were too small and the third house was so small nobody could live in it[ Thus\ although he was scored as using both a reduction and a part distortion strategy\ the distortion involved changing the size of the parts[
General discussion All of the children with focal brain injury presented in this study showed notable and continuous improvement in their graphic representation of {possible| houses[ Over
J[ Stiles et al[:The development of drawing in children with congenital focal brain injury
298
Fig[ 5[ The longitudinal series of impossible house drawings for six children with LH injury are shown[
time the houses became more complex\ incorporating more features and more complex sets of spatial structures[ For example\ by the late school age period\ many of the children attempted to represent three!dimensionality in their drawings[ However\ the consistency of the children|s depictions over time is also striking[ Consistent with earl! ier literature\ it appears that the children did indeed
develop formulaic graphic expressions for representing houses[ Thus\ in the series presented here\ we see the emergence and the elaboration of graphic formulas in all of the children tested[ The graphic formula appears to be a useful and e.cient strategy for representing objects\ here houses\ symbolically[ It is particularly notable that even those children with RH injury with documented
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J[ Stiles et al[:The development of drawing in children with congenital focal brain injury
Fig[ 6[ The longitudinal series of impossible house drawings for six children with RH injury are shown[
di.culty in early graphic production "i[e[ P[K[\ M[B[\ J[D[\ E[M[# were able to develop graphic formulas which accurately portrayed houses[ The question asked at the beginning of this study was how do children who show such marked impairment early in development improve so dramatically< One possible answer is that their improvement was due to some general
underlying recovery of their spatial analytic skills[ By this account\ the children should have become pro_cient in drawing gradually\ and eventually reach a level of per! formance that was indistinguishable from other children[ An alternative possibility is that the task of gradually building a repertoire of formulas served compensatory strategy which allowed for a much more limited form of
J[ Stiles et al[:The development of drawing in children with congenital focal brain injury
improvement[ By this account performance would improve such that the drawing of particular graphic objects would gradually become indistinguishable from those of other children\ but the range and ~exibility of the children|s drawings would be more limited[ Under these conditions\ children with RH injury would be much more reliant on these formulaic expressions than children without such de_cits[ The data from the impossible _g! ures task supports the later account[ The results of this study showed that children with RH injury did not produce new or novel graphic forms with new and unusual organization properties[ They did not alter the spatial structures of their drawing formulas[ The most common strategies were reduction\ rotation and object conversion[ None of these strategies required the child to generate an alternative spatial con_guration\ and thus did not require the child to re!analyze the spatial properties of the target form[ In several cases the children used rotation\ which clearly has a spatial component[ However in executing the drawings\ the children rotated their arms and heads\ and thus generated the drawing from a canonical perspective[ It might be argued that the present task did not speci_cally instruct the child to alter the structure of the house\ and that the children might have used distortion strategies with greater frequency if explicitly asked to do so[ While this is a possibility that should be tested\ the resistance to spatial distortion stra! tegies among children with RH injury in the present stud! ies is striking[ Over periods of three to _ve years\ spanning the school age period the absence of distortion strategies is notable\ and contrasts markedly with the performance of children with LH injury[ It should also be noted that this failure to deviate from preexisting graphic formulas did not mean that the children lacked imaginative ~exibility\ or that they failed to understand the task[ Indeed they came up with many very creative solutions for this rather unusual task[ In all but a few cases the children|s solution to the problem of making an impossible house fell with the range of stra! tegies used by normally developing children[ What was unusual among children with RH injury was the dis! tribution of strategies\ and speci_cally\ their extremely limited use of what is the dominant strategy among nor! mal children\ con_gural distortion[ In summary\ the children with RH injury reported in this study showed clear evidence of development and apparent recovery of spatial ability on a free drawing task in which they were simply asked to draw a house[ In contrast to their performance early in development ð18Ł\ the children produced organized and well!integrated forms[ This could be interpreted as representing an initial\ brief period of developmental delay followed by recovery[ However\ the children|s performance on the impossible _gures task suggests an alternative explanation[ Those data suggest that rather than general recovery of basic spatial integrative skills\ the children with RH injury\ like the other children in the study\ appear to have acquired a repertoire of graphic formulas[ These formulas allowed
200
the children to perform at the level of their peers in the free drawing task[ However\ the children with RH injury appear to rely upon these formulas more than normal children or children with LH injury[ This reliance on formulaic drawing strategies became evident within the context of the impossible _gures task[ While all of the children with RH injury successfully solved the problem of producing an {impossible| house\ they rarely used the strategy that is adopted most frequently by normal chil! dren and children with LH injury\ con_gural distortion[ Thus\ the children with RH injury were able to solve the problem of impossibility\ but they did not use strategies that involve spatial reorganization[ In this sense\ the chil! dren are limited in the ~exibility of their graphic expression[ It is this lack of ~exibility with the structure of formula itself that suggests a persistent di.culty in their ability to reorganize and reformulate the spatial structure of the graphic object[ If this is the case then\ while the children are clearly demonstrating functional recovery in their acquisition of graphic formulas\ the degree of recovery may be more restricted than the data _rst suggest[
References 0[ Alajouanine\ T[ and Lhermitte\ F[ Acquired aphasia in children[ Brain 77\ 442Ð451\ 0854[ 1[ Aram\ D[ M[\ Ekelman\ B[ L[\ Rose\ D[ F[ and Whi! taker\ H[ A[ Verbal and cognitive sequelae following unilateral lesions acquired in early childhood[ Jour! nal of Clinical and Experimental Neuropsycholo`y 6\ 44Ð67\ 0874[ 2[ Aram\ D[ M[\ Ekelman\ B[ L[ and Whitaker\ H[ A[ Spoken syntax in children with acquired unilateral hemisphere lesions[ Brain and Lan`ua`e 16\ 64Ð099\ 0875[ 3[ Aram\ D[ M[\ Rose\ D[ F[\ Rekate\ H[ L[ and Whitaker\ H[ A[ Acquired capsular:striatal aphasia in childhood[ Archives of Neurolo`y 39\ 503Ð506\ 0872[ 4[ Brown\ J[ W[ and Ja}e\ J[ Hypothesis on cerebral dominance[ Neuropsycholo`ia 02"0#\ 096Ð009\ 0864[ 5[ Carlson\ J[\ Netley\ C[\ Hendrick\ E[ and Pritchard\ J[ A reexamination of intellectual abilities in hemi! decorticated patients[ Transactions of the American Neurolo`ical Association 82\ 087Ð190\ 0857[ 6[ Day\ P[ S[ and Ulatowska\ H[ K[ Perceptual\ cogni! tive\ and linguistic development after early hemi! spherectomy] Two case studies[ Brain and Lan`ua`e 6\ 06Ð22\ 0868[ 7[ Fenson\ L[ The transition from construction to sket! ching in children|s drawings[ In Visual Order] The Nature and Development of Pictorial Representation\ N[H[ Freeman and M[V[ Cox "Editors#\ pp[ 263Ð273[ Cambridge\ New York\ 0874[ 8[ Freeman\ N[ H[ Strate`ies of Representation in Youn` Children] Analysis of Spatial Skills and Drawin` Pro! cesses[ Academic Press\ New York\ 0879[
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09[ Goodnow\ J[ J[ Children|s Drawin`s[ Open\ London\ 0866[ 00[ Gott\ P[ S[ Cognitive abilities following right and left hemispherectomy[ Cortex 8\ 155Ð163\ 0862[ 01[ Gridley\ P[ F[ Graphic!representation of a man by four!year!old children in nine prescribed drawing situations[ Genetic Psycholo`y Mono`raphs 19\ 072Ð 249\ 0827[ 02[ Hammill\ D[ and Irwin\ O[ C[ I[Q[ di}erences of right and left spastic hemiplegic children[ Perceptual and Motor Skills 11\ 082Ð083\ 0855[ 03[ Karmilo}!Smith\ A[ Constraints on representational change] Evidence from children|s drawing[ Co`nition 23\ 46Ð72\ 0889[ 04[ Krashen\ S[ D[ Lateralization\ language learning\ and the critical period] Some new evidence[ Lan`ua`e Learnin` 12"0#\ 52Ð64\ 0862[ 05[ Lenneberg\ E[ The Biolo`ical Foundations of Lan`! ua`e[ Wiley\ New York\ 0856[ 06[ Markham\ S[ An item analysis of children|s drawings of a house[ Journal of Clinical Psycholo`y 09\ 074Ð 076\ 0843[ 07[ Mc_e\ J[ The e}ects of hemispherectomy on intel! lectual functioning in cases of infantile hemiplegia[ Journal of Neurolo`y\ Neurosur`ery\ and Psychiatry 13\ 139Ð138\ 0850[ 08[ Reed\ J[ C[ and Reitan\ R[ M[ Verbal and per! formance di}erences among brain!injured children with lateralized motor de_cits[ Neuropsycholo`ia 8\ 390\ 0860[ 19[ Rudel\ R[ G[ and Teuber\ H[ L[ Spatial orientation in normal children and in children with early brain damage[ Neuropsycholo`ia 8\ 390Ð396\ 0860[ 10[ Rudel\ R[ G[\ Teuber\ H[ L[ and Twitchell\ T[ Levels of impairment of sensorimotor function in children with early brain damage[ Neuropsycholo`ia 01\ 84Ð 097\ 0863[ 11[ Stiles\ J[\ Stern\ C[\ Trauner\ D[ and Nass\ R[ Devel! opmental change in spacial grouping activity among children with early focal brain injury] Evidence from a modeling task[ Brain and Co`nition\ 23\ 35Ð51 "0885#[ 12[ Stiles\ J[ The early use of graphic formulas] Case study reports of graphic formula production by 1! to 2!year!old children[ International Journal of Devel! opmental Psycholo`y\ 016Ð038\ 0884[
13[ Stiles\ J[ Plasticity and development] Evidence from children with early occurring focal brain injury[ In Maturational Windows and Adult Cortical Plasticity\ B[ Julesz and I[ Kovacs "Editors#\ Vol[ XXIV[ Addison!Wesley\ Santa Fe\ CA\ 0884[[ 14[ Stiles\ J[ and Thal\ D[ Linguistic and spatial cognitive development following early focal brain injury] Pat! terns of de_cit and recovery[ In Brain Development and Co`nition\ M[ Johnson "Editor#\ pp[ 533Ð553[ Blackwell\ Cambridge\ MA\ 0882[ 15[ Stiles\ J[ and Nass\ R[ Spatial grouping activity in young children with congenital right or left hemi! sphere brain injury[ Brain and Co`nition 04\ 190Ð111\ 0880[ 16[ Stiles!Davis\ J[\ Sugarman\ S[ and Nass\ R[ The development of spatial and class relations in four young children with right cerebral hemisphere dam! age] Evidence for early spatial!constructive de_cit[ Brain and Co`nition 3\ 277Ð301\ 0874[ 17[ Stiles!Davis\ J[ Spatial dysfunction in young children with right cerebral hemisphere injury[ In Spatial Co`! nition] Brain Bases and Development\ J[ Stiles!Davis\ M[ Kritchevsky\ and U[ Bellugi "Editor#[ Lawrence Erlbaum\ Hillsdale\ N[J[\ 0877[ 18[ Stiles!Davis\ Janowsky\ J[\ Engel\ M[ and Nass\ R[ Drawing ability in four young children with con! genital unilateral brain lesions[ Neuropsycholo`ia 15\ 248Ð260\ 0877[ 29[ Swindell\ C[ S[\ Hoolland\ A[ L[\ Fromm\ D[ and Greenhouse\ J[ B[ Characteristics of recovery of drawing ability in left and right brain!damaged pat! ients[ Brain and Co`nition 6\ 05Ð29\ 0877[ 20[ Thomas\ G[V[\ and Silk\ A[M[ "0889#[ An Intro! duction to the Psycholo`y of Children|s Drawin`s[ Harvester Wheatsheaf\ New York[[ 21[ van Sommers\ P[ Drawin` and Co`nition] Descriptive and Experimental Studies of Graphic Production Pro! cesses[ Cambridge University Press\ New York\ 0873[ 22[ Vargha!Khadem\ F[\ O|Gorman\ A[ and Watters\ G[ Aphasia and handedness in relation to hemispheric sides\ age at injury and severity of cerebral lesion during childhood[ Brain 097\ 556Ð585\ 0874[ 23[ Stiles\ J[\ Delis\ D[ C[ and Tada\ W[ L[ GlobalÐlocal processing in preschool children[ Child Development 51\ 0147Ð0164\ 0880[