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An experimental investigation of developmental differences in ability to recognise faces presented to the left and right cerebral hemispheres
Neuropsychologia, t976, Vol. 14, pp. 495 to 498. Pergamon Press. Printed in England.
NOTE AN EXPERIMENTAL INVESTIGATION OF DEVELOPMENTAL DIFFERENCES IN ABILITY TO RECOGNISE FACES PRESENTED TO THE LEFT AND RIGHT CEREBRAL HEMISPHERES ANDREW W. YOUNG and HADYN D. ELLIS Department of Psychology, University of Aberdeen, Old Aberdeen AB9 2UB, Scotland
(Received 13 November 1975) Abstract--Right-handed children aged 5, 7 and 11 yr were shown faces presented briefly to their left visual field or right visual field. After a short interval they were asked whether a comparison face was the same as or different to the face they had seen. The results indicate right hemisphere superiority at all three ages and are discussed in the context of theoretical accounts of the development of lateralisation of brain function. INTRODUCTION MUCH EVmENCE relating to asymmetries of human cerebral function has been gathered from studies of patients with cerebral dysfunction or damage [1], particularly those with section of the corpus callosum and anterior commissures [2]. It is also possible to study asymmetries of function in intact brains by utilising the fact that each cerebral hemisphere subserves its contralateral limbs, ear and binocular visual hemi-field [3]. The results of such studies suggest that for right-handed adults the left cerebral hemisphere is dominant for verbal and linguistic functions, with right hemisphere dominance for spatial functions and analysis of non-linguistic sound patterns. The right hemisphere has also been found to be superior at processing visual stimuli (Kar~URAand DtrRr,rrORD [4]) and pictures of faces in particular (RIZZOLAa'rI, U~ILTA and BERLtr¢CHI [5], HILLIARD [6], ELLIS a n d SHEPHERD [7]).
Theories to account for the development of hemisphere dominance have been proposed by ANr~ETr [8, 9] and LENNEBERG[10]. These incorporate available data on the course of language lateralisation and recovery from brain damage in childhood, but there is little developmental information available concerning the lateralisation of functions associated with the right hemisphere. It is often reported that males, both adults and boys, are superior to females on tests involving proficiency in spatial skills whilst females are superior on tests of linguistic skills [11], but this evidence is indirect. BUFFERYand GRAY [12], reviewing the available data (including Buffery's studies of sex differences in simultaneous inter-modal matching by children) suggest that girls develop a more left-sided cerebral dominance for language function than boys, and that boys develop a more bilateral representation of spatial function than girls. The present study investigated the development of lateralisation of processing of pictorial stimuli with a technique similar to that used by ELLISand SHEPHERDto demonstrate right hemisphere superiority in adults. This involved presentation of pictures of faces to subjects' right or left hemispheres by showing them tachistoscopically in the left visual field (LVF) or right visual field (RVF). A comparison face was presented after an interval and subjects were asked whether this was the same as the face they had seen or different. One difficulty in using such a technique with children is that failure to look at the fixation point defining the border of the LVF and RVF will lead to stimuli presented in what the experimenter believes to be the subject's LVF arriving at either the left or right hemispheres, and hence an artifactual result in the direction of apparent non-lateralisation. This is, of course, increasingly likely the younger the age of the children studied. To minimise this possibility, the present study used material presented centrally (i.e. at the fixation poin0 as well as peripherally (left or right of the fixation poin0, and only subjects whose performance was no poorer with centrally presented stimuli than stimuli presented to either periphery were included. SUBJECTS Three groups of right-handed children, mean ages 5 yr 8 months, 7 yr 8 months, and 11 yr 10 months, were drawn from two local schools in predominantly middle-class areas. The criteria for classifying children 495
496
NOTE
as right-handed consisted of a writing test and teacher's evaluation. Twenty-two 5 yr old children (13 boys, 9 girls), thirty-three 7 yr olds (20 boys, 13 girls), and sixteen 11 yr olds (8 boys, 8 girls) were tested, in order to build up groups of 14 children of each age (7 boys, 7 girls) who satisfied the criterion of equal or better performance with the central stimuli than with stimuli presented to either periphery. METHOD On each trial the child was asked to fixate a small black spot in the centre of a two-field tachistoscope adaptation field and a picture of a face was presented briefly in the right, centre, or left of the tachistoscope field. The 5 yr old children were given presentation times of 70 ms for each stimulus, the 7 yr old group had presentation times of 50 ms, and the 11 yr old group 40 ms. These times were determined by pilot work in order to obtain sufficient errors at each age level to reveal any lateralisation effect without degenerating to chance level performance. After each stimulus face had occurred the child was shown a comparison face mounted on a piece of white card and asked if this was the same as the face he had seen, or different in any way. Sixty trials were given, 40 of which used LVF and RVF stimuli described by ELLIS and SHEPHERD [7] and 20 of which formed the centre control. The stimuli subtended a visual angle of 3° 48', and the boundaries of the RVF and LVF stimuli were offset from the centre by 1° 16'. There were equal numbers of LVF, centre, and RVF trials, with equal numbers of same and different pairs in each condition. The order of presentation of stimuli was randomised and half the subjects of each sex were given the stimuli in forward order, half in reverse order. The LVF and RVF presentation of particular stimuli was also balanced between subjects and across sexes. Experimental trials were preceded by one demonstration and six practice trials (two RVF, two centre, two LVF). During these trials any errors made were brought to the child's attention by repeating the trial until a correct decision was achieved. Care was taken in emphasising the importance of always looking at the fixation point, and the subject was reminded to 'look at the dot' before every experimental trial (the form of this instruction was varied as much as possible to minimise the danger of its being ignored). The fact that the pairs of faces were to be 'sometimes the same and sometimes different' was also emphasised. After every trial the experimenter provided encouragement by saying 'good'. RESULTS The results of the investigation are summarised in Table 1. An analysis of variance indicates that the difference between the number of LVF and RVF errors within the three age levels is significant at the 0.001 level ( F = 22-68, df 1,39). The difference among ages is not significant (F < 1), and there is no significant interaction ( F < 1). Table 1. Mean error rates and between subjects standard deviations for stimuli falling in the left visual field (LVF), the centre, and the right visual field (RVF) of boys and girls aged 5, 7 and 11 yr.
X Boys SD included in the study
5 yr old group 7 yr old group 11 yr old group LVF Centre RVF Total LVF Centre RVF Total LVF Centre RVF Total 5'14 3"86 7.00 16.00 5.71 3"43 7"00 16-14 5'43 3.71 6"57 15"71 1"95 2"19 1"63 5.03 1'38 1'40 1.00 2"97 1"72 0.76 1"90 2.63
5'86 2-54
3"57 2-51
7"86 2-41
17"29 6.18
7-00 1.73
4"29 l'70
8'14 2'54
19'42 6"29 5-06 2.06
4'29 1.89
7"86 18"43 1.77 4"89
Overall Ji" for subjects included in the study
5'50
3.71
7-43
16"64
6.36
3"86
7.57
17.29
5.86
4.29
7.21
17"36
.gfor excluded subjects
4"66
6'33
6"66 17.65
6.76
7"29
6'17
20.22
5.00
9"50
4.50
19.00
Girls SD included in the study
The total number of errors made by the experimental subjects and those who failed to meet the experimental criteria (collapsed data for all ages) were compared by means of a t test, the superior performance of the experimental group just failing to achieve significance (t = 1"98, df = 65, P > 0"05). The difference between the LVF and RVF error totals for the children failing to meet the criteria (all ages collapsed) is also non-significant (t = 0"13, df = 24, P > 0.05). Twenty of the excluded children were boys and only
NOtE
497
nine girls; this sex difference is significant (X ~ = 4"0, d f = 1, P < 0"05), but the differences between the numbers of LVF and RVF errors made by boys and girls meeting the experimental criterion did not achieve significance (t < 1). DISCUSSION The results indicate that lateralisation is present in right-handed children at age 5, 7 and 11, with the right hemisphere being superior on this task (LVF stimuli are processed initially by the right hemisphere). There is no evidence of any increase in the degree of lateralisation with increasing age, in contrast to the suggestions of ZANGWILL [1] and LEr~N~ERG [10] that lateralisation of abilities is established gradually during childhood. However, it is possible that the method used was not sufficiently sensitive to detect increases in lateralisation which may have been present, due possibly to the necessity of using different stimulus presentation times with the different age groups. Studies with other methods and materials may reveal a different situation in this respect. K.UaURA [13] found that spoken material arriving at the right ear (and hence predominantly left hemisphere) was more accurately reported than spoken material arriving at the left ear from at least age 4. As she points out, such evidence for a left hemisphere predominance for speech perception from an early age does not rule out greater flexibility of organisation in the young brain nor the participation of the other hemisphere in the same functions. The same qualifications apply to the present findings. The importance of the centrally presented control stimuli is clear from the fact that the children excluded from the experimental groups show no significant lateralisation effect. These children are probably a heterogeneous collection of individuals who failed to obey the experimental instructions and those for whom the tachistoscope setting (fixed for each age rather than each individual) was unsuitable. However, there may be some more fundamental difference such as a lower degree of lateralisation, or more bilateral representation of function among children not meeting the experimental criterion. MARCEL et al. [14] found evidence of a greater degree of lateralisation of word recognition in the left hemisphere in good readers than poor readers, and a possible speculation would be that they would also show greater lateralisation of right hemisphere skills. However, this was not confirmed by MARCEL and RAJAN [15], who conclude that the development of hemispheric specialisation for verbal processing is unrelated to that for visuo-spatial processing. The teachers of the children involved in the present study were asked to comment on any obvious differences between those meeting and failing to meet the experimental criterion (such as attentiveness or reading ability), but none were reported. The fact that there were significantly more boys than girls among the excluded children is interesting, and consistent with the common finding that girls tend to be more advanced than boys on a variety of intellectual skills. BUFFERY and GRAY'S [12] claim that boys have a more bilateral cerebral representation of spatial function than girls of the same age is interesting in this respect because spatial functions are often thought to be lateralised in favour of the right hemisphere. The present study does not reveal sex differences in lateralisation of face recognition among the subjects meeting the centre criterion, but the fact that more boys than girls fail to meet this criterion could be interpreted as indicating a greater degree of hemispheric competition' among the boys. Clearly, a more careful analysis of the factors differentiating the children meeting the criterion from those who do not is required. In the meantime, there is good reason to believe that lateralisation of visual information processing is well advanced by age 5. Acknowledgements The authors would like to thank staff and pupils of Mile End School and Airyhall School, particularly Mr. SMITh, Mr. Cotrrrs, and Miss CLARK, for their generous co-operation in this study. REFERENCES
1. ZANGWILL, O. L. Cerebral Dominance and its Relation to Psychological Function. Oliver & Boyd Edinburgh, 1960. 2. G A Z Z A ~ A , M. S. The Bisected Brain. Appleton-Century-Crofts, New York, 1970. 3. DIMOND, S. J. and BEAUMONT,J. G. Experimental studies of hemisphere function of the human brain. In Hemisphere Function in the Human Brain, S. J. DIMOND and J. G. BEAUMONT (Editors). Paul Elek, London, 1974. 4. KIMURA, D. and DURrCFORO, M. Normal studies on the function of the right hemisphere in vision. In Hemisphere Function in the Human Brain, S. J. DIMOND and J. G. BEAUMONT (Editors). Paul Elek, London, 1974. 5. RIZZOLATrI, G., UMILXA, C. and BERLUCCrtI, G. Opposite superiorities of the right and left cerebral hemispheres in discriminative reaction time to physiognomic and alphabetical material. Brain 94, 431442, 1971. 6. HILLIARD, R. D. Hemispheric laterality effects on a facial recognition task in normal subjects. Cortex 9, 246-258, 1973.
498
NOTE
7. ELLIS, H. D. and SHEPHERD,J. Recognition of upright and inverted faces presented in the left and right visual fields. Cortex 11.3-7, 1975. 8. ANNEX, M. A model of the inheritance of handedness and cerebral dominance. Nature, (Lend.) 204, 5960,1964. 9. ANNETT,M. The distribution of manual asymmetry. Br. J. Psychol. 63, 343-358, 1972. 10. LENNEBERG,E. H. Biological Foundations of Language. John Wiley, New York, 1967. 11. GUILFORD,J. P. The Nuture of Human Intelligence. McGraw-Hill, New York, 1967. 12. BUFFERY,A. W. H. and GRAY, J. A. Sex differences in the development of spatial and linguistic skills. In Gender Differences: Their Ontogeny and Significance, C. OUNSTEDand D. C. TAYLOR(Editors). Churchill Livingstone, Edinburgh, 1973. 13. KIMURA, D. Speech lateralisation in young children as determined by an auditory test. J. cotp. physiol. Psychol. 56,899~902, 1963. 14. MARCEL,T., KATZ, L. and SMITH,M. Laterality and reading proficiency. Neuropsychologia 1974.
15. MARCEL,T. and RAJAN, P. Lateral specialisation readers. Neuropsychologia 13,489-497, 1975.
12,131-139,
for recognition of words and faces in good and poor
RQsum6 : On a pr6sent6 brievement a des enfants droitiers ages de 5, 7 et 11 ans des repr&.entations
de visages soit a l'hemichamp
gauche soit B l'hemichamp droit. AprSs un bref intervalle, on leur demandait de comparer un visage pour dire s'il etait le meme
ou
different de celui qu'il venait de voir. Les resultats montrent une superiorit& de 1'hemisphSre droit aux 3 dyes. On discute ces r&xltats en tenant compte des points de we
theoriques sur le d&eloppe-
ment de la lateralisation des fonctions c&X?brales.
Deutschsprachige
Zusammenfassung:
Rechtshgndige IiiEder im Alter von 5, 7 und 11 Jahren bekamen Gesichter im rechten und linken Gesi.chtsfeldkurzzeitig gezeigt. Nach einem Interval1 wurden sie gefragt, ob ein Vergleichsgesicht mit demjenigen, das sie vorher sahen, identisch oder different war, Die Ergebnisse sprachen fur eine rech'cshemispharische tiberlegenheitin allen drei Altersstufen. Im Context mit theoretischen Erdrterungen iiberdie Entwicklung der funktionellen Lateralisierung des Gehirns wurden die Ergebnisse diskutlert.
NOTE AN EXPERIMENTAL INVESTIGATION OF DEVELOPMENTAL DIFFERENCES IN ABILITY TO RECOGNISE FACES PRESENTED TO THE LEFT AND RIGHT CEREBRAL HEMISPHERES ANDREW W. YOUNG and HADYN D. ELLIS Department of Psychology, University of Aberdeen, Old Aberdeen AB9 2UB, Scotland
(Received 13 November 1975) Abstract--Right-handed children aged 5, 7 and 11 yr were shown faces presented briefly to their left visual field or right visual field. After a short interval they were asked whether a comparison face was the same as or different to the face they had seen. The results indicate right hemisphere superiority at all three ages and are discussed in the context of theoretical accounts of the development of lateralisation of brain function. INTRODUCTION MUCH EVmENCE relating to asymmetries of human cerebral function has been gathered from studies of patients with cerebral dysfunction or damage [1], particularly those with section of the corpus callosum and anterior commissures [2]. It is also possible to study asymmetries of function in intact brains by utilising the fact that each cerebral hemisphere subserves its contralateral limbs, ear and binocular visual hemi-field [3]. The results of such studies suggest that for right-handed adults the left cerebral hemisphere is dominant for verbal and linguistic functions, with right hemisphere dominance for spatial functions and analysis of non-linguistic sound patterns. The right hemisphere has also been found to be superior at processing visual stimuli (Kar~URAand DtrRr,rrORD [4]) and pictures of faces in particular (RIZZOLAa'rI, U~ILTA and BERLtr¢CHI [5], HILLIARD [6], ELLIS a n d SHEPHERD [7]).
Theories to account for the development of hemisphere dominance have been proposed by ANr~ETr [8, 9] and LENNEBERG[10]. These incorporate available data on the course of language lateralisation and recovery from brain damage in childhood, but there is little developmental information available concerning the lateralisation of functions associated with the right hemisphere. It is often reported that males, both adults and boys, are superior to females on tests involving proficiency in spatial skills whilst females are superior on tests of linguistic skills [11], but this evidence is indirect. BUFFERYand GRAY [12], reviewing the available data (including Buffery's studies of sex differences in simultaneous inter-modal matching by children) suggest that girls develop a more left-sided cerebral dominance for language function than boys, and that boys develop a more bilateral representation of spatial function than girls. The present study investigated the development of lateralisation of processing of pictorial stimuli with a technique similar to that used by ELLISand SHEPHERDto demonstrate right hemisphere superiority in adults. This involved presentation of pictures of faces to subjects' right or left hemispheres by showing them tachistoscopically in the left visual field (LVF) or right visual field (RVF). A comparison face was presented after an interval and subjects were asked whether this was the same as the face they had seen or different. One difficulty in using such a technique with children is that failure to look at the fixation point defining the border of the LVF and RVF will lead to stimuli presented in what the experimenter believes to be the subject's LVF arriving at either the left or right hemispheres, and hence an artifactual result in the direction of apparent non-lateralisation. This is, of course, increasingly likely the younger the age of the children studied. To minimise this possibility, the present study used material presented centrally (i.e. at the fixation poin0 as well as peripherally (left or right of the fixation poin0, and only subjects whose performance was no poorer with centrally presented stimuli than stimuli presented to either periphery were included. SUBJECTS Three groups of right-handed children, mean ages 5 yr 8 months, 7 yr 8 months, and 11 yr 10 months, were drawn from two local schools in predominantly middle-class areas. The criteria for classifying children 495
496
NOTE
as right-handed consisted of a writing test and teacher's evaluation. Twenty-two 5 yr old children (13 boys, 9 girls), thirty-three 7 yr olds (20 boys, 13 girls), and sixteen 11 yr olds (8 boys, 8 girls) were tested, in order to build up groups of 14 children of each age (7 boys, 7 girls) who satisfied the criterion of equal or better performance with the central stimuli than with stimuli presented to either periphery. METHOD On each trial the child was asked to fixate a small black spot in the centre of a two-field tachistoscope adaptation field and a picture of a face was presented briefly in the right, centre, or left of the tachistoscope field. The 5 yr old children were given presentation times of 70 ms for each stimulus, the 7 yr old group had presentation times of 50 ms, and the 11 yr old group 40 ms. These times were determined by pilot work in order to obtain sufficient errors at each age level to reveal any lateralisation effect without degenerating to chance level performance. After each stimulus face had occurred the child was shown a comparison face mounted on a piece of white card and asked if this was the same as the face he had seen, or different in any way. Sixty trials were given, 40 of which used LVF and RVF stimuli described by ELLIS and SHEPHERD [7] and 20 of which formed the centre control. The stimuli subtended a visual angle of 3° 48', and the boundaries of the RVF and LVF stimuli were offset from the centre by 1° 16'. There were equal numbers of LVF, centre, and RVF trials, with equal numbers of same and different pairs in each condition. The order of presentation of stimuli was randomised and half the subjects of each sex were given the stimuli in forward order, half in reverse order. The LVF and RVF presentation of particular stimuli was also balanced between subjects and across sexes. Experimental trials were preceded by one demonstration and six practice trials (two RVF, two centre, two LVF). During these trials any errors made were brought to the child's attention by repeating the trial until a correct decision was achieved. Care was taken in emphasising the importance of always looking at the fixation point, and the subject was reminded to 'look at the dot' before every experimental trial (the form of this instruction was varied as much as possible to minimise the danger of its being ignored). The fact that the pairs of faces were to be 'sometimes the same and sometimes different' was also emphasised. After every trial the experimenter provided encouragement by saying 'good'. RESULTS The results of the investigation are summarised in Table 1. An analysis of variance indicates that the difference between the number of LVF and RVF errors within the three age levels is significant at the 0.001 level ( F = 22-68, df 1,39). The difference among ages is not significant (F < 1), and there is no significant interaction ( F < 1). Table 1. Mean error rates and between subjects standard deviations for stimuli falling in the left visual field (LVF), the centre, and the right visual field (RVF) of boys and girls aged 5, 7 and 11 yr.
X Boys SD included in the study
5 yr old group 7 yr old group 11 yr old group LVF Centre RVF Total LVF Centre RVF Total LVF Centre RVF Total 5'14 3"86 7.00 16.00 5.71 3"43 7"00 16-14 5'43 3.71 6"57 15"71 1"95 2"19 1"63 5.03 1'38 1'40 1.00 2"97 1"72 0.76 1"90 2.63
5'86 2-54
3"57 2-51
7"86 2-41
17"29 6.18
7-00 1.73
4"29 l'70
8'14 2'54
19'42 6"29 5-06 2.06
4'29 1.89
7"86 18"43 1.77 4"89
Overall Ji" for subjects included in the study
5'50
3.71
7-43
16"64
6.36
3"86
7.57
17.29
5.86
4.29
7.21
17"36
.gfor excluded subjects
4"66
6'33
6"66 17.65
6.76
7"29
6'17
20.22
5.00
9"50
4.50
19.00
Girls SD included in the study
The total number of errors made by the experimental subjects and those who failed to meet the experimental criteria (collapsed data for all ages) were compared by means of a t test, the superior performance of the experimental group just failing to achieve significance (t = 1"98, df = 65, P > 0"05). The difference between the LVF and RVF error totals for the children failing to meet the criteria (all ages collapsed) is also non-significant (t = 0"13, df = 24, P > 0.05). Twenty of the excluded children were boys and only
NOtE
497
nine girls; this sex difference is significant (X ~ = 4"0, d f = 1, P < 0"05), but the differences between the numbers of LVF and RVF errors made by boys and girls meeting the experimental criterion did not achieve significance (t < 1). DISCUSSION The results indicate that lateralisation is present in right-handed children at age 5, 7 and 11, with the right hemisphere being superior on this task (LVF stimuli are processed initially by the right hemisphere). There is no evidence of any increase in the degree of lateralisation with increasing age, in contrast to the suggestions of ZANGWILL [1] and LEr~N~ERG [10] that lateralisation of abilities is established gradually during childhood. However, it is possible that the method used was not sufficiently sensitive to detect increases in lateralisation which may have been present, due possibly to the necessity of using different stimulus presentation times with the different age groups. Studies with other methods and materials may reveal a different situation in this respect. K.UaURA [13] found that spoken material arriving at the right ear (and hence predominantly left hemisphere) was more accurately reported than spoken material arriving at the left ear from at least age 4. As she points out, such evidence for a left hemisphere predominance for speech perception from an early age does not rule out greater flexibility of organisation in the young brain nor the participation of the other hemisphere in the same functions. The same qualifications apply to the present findings. The importance of the centrally presented control stimuli is clear from the fact that the children excluded from the experimental groups show no significant lateralisation effect. These children are probably a heterogeneous collection of individuals who failed to obey the experimental instructions and those for whom the tachistoscope setting (fixed for each age rather than each individual) was unsuitable. However, there may be some more fundamental difference such as a lower degree of lateralisation, or more bilateral representation of function among children not meeting the experimental criterion. MARCEL et al. [14] found evidence of a greater degree of lateralisation of word recognition in the left hemisphere in good readers than poor readers, and a possible speculation would be that they would also show greater lateralisation of right hemisphere skills. However, this was not confirmed by MARCEL and RAJAN [15], who conclude that the development of hemispheric specialisation for verbal processing is unrelated to that for visuo-spatial processing. The teachers of the children involved in the present study were asked to comment on any obvious differences between those meeting and failing to meet the experimental criterion (such as attentiveness or reading ability), but none were reported. The fact that there were significantly more boys than girls among the excluded children is interesting, and consistent with the common finding that girls tend to be more advanced than boys on a variety of intellectual skills. BUFFERY and GRAY'S [12] claim that boys have a more bilateral cerebral representation of spatial function than girls of the same age is interesting in this respect because spatial functions are often thought to be lateralised in favour of the right hemisphere. The present study does not reveal sex differences in lateralisation of face recognition among the subjects meeting the centre criterion, but the fact that more boys than girls fail to meet this criterion could be interpreted as indicating a greater degree of hemispheric competition' among the boys. Clearly, a more careful analysis of the factors differentiating the children meeting the criterion from those who do not is required. In the meantime, there is good reason to believe that lateralisation of visual information processing is well advanced by age 5. Acknowledgements The authors would like to thank staff and pupils of Mile End School and Airyhall School, particularly Mr. SMITh, Mr. Cotrrrs, and Miss CLARK, for their generous co-operation in this study. REFERENCES
1. ZANGWILL, O. L. Cerebral Dominance and its Relation to Psychological Function. Oliver & Boyd Edinburgh, 1960. 2. G A Z Z A ~ A , M. S. The Bisected Brain. Appleton-Century-Crofts, New York, 1970. 3. DIMOND, S. J. and BEAUMONT,J. G. Experimental studies of hemisphere function of the human brain. In Hemisphere Function in the Human Brain, S. J. DIMOND and J. G. BEAUMONT (Editors). Paul Elek, London, 1974. 4. KIMURA, D. and DURrCFORO, M. Normal studies on the function of the right hemisphere in vision. In Hemisphere Function in the Human Brain, S. J. DIMOND and J. G. BEAUMONT (Editors). Paul Elek, London, 1974. 5. RIZZOLATrI, G., UMILXA, C. and BERLUCCrtI, G. Opposite superiorities of the right and left cerebral hemispheres in discriminative reaction time to physiognomic and alphabetical material. Brain 94, 431442, 1971. 6. HILLIARD, R. D. Hemispheric laterality effects on a facial recognition task in normal subjects. Cortex 9, 246-258, 1973.
498
NOTE
7. ELLIS, H. D. and SHEPHERD,J. Recognition of upright and inverted faces presented in the left and right visual fields. Cortex 11.3-7, 1975. 8. ANNEX, M. A model of the inheritance of handedness and cerebral dominance. Nature, (Lend.) 204, 5960,1964. 9. ANNETT,M. The distribution of manual asymmetry. Br. J. Psychol. 63, 343-358, 1972. 10. LENNEBERG,E. H. Biological Foundations of Language. John Wiley, New York, 1967. 11. GUILFORD,J. P. The Nuture of Human Intelligence. McGraw-Hill, New York, 1967. 12. BUFFERY,A. W. H. and GRAY, J. A. Sex differences in the development of spatial and linguistic skills. In Gender Differences: Their Ontogeny and Significance, C. OUNSTEDand D. C. TAYLOR(Editors). Churchill Livingstone, Edinburgh, 1973. 13. KIMURA, D. Speech lateralisation in young children as determined by an auditory test. J. cotp. physiol. Psychol. 56,899~902, 1963. 14. MARCEL,T., KATZ, L. and SMITH,M. Laterality and reading proficiency. Neuropsychologia 1974.
15. MARCEL,T. and RAJAN, P. Lateral specialisation readers. Neuropsychologia 13,489-497, 1975.
12,131-139,
for recognition of words and faces in good and poor
RQsum6 : On a pr6sent6 brievement a des enfants droitiers ages de 5, 7 et 11 ans des repr&.entations
de visages soit a l'hemichamp
gauche soit B l'hemichamp droit. AprSs un bref intervalle, on leur demandait de comparer un visage pour dire s'il etait le meme
ou
different de celui qu'il venait de voir. Les resultats montrent une superiorit& de 1'hemisphSre droit aux 3 dyes. On discute ces r&xltats en tenant compte des points de we
theoriques sur le d&eloppe-
ment de la lateralisation des fonctions c&X?brales.
Deutschsprachige
Zusammenfassung:
Rechtshgndige IiiEder im Alter von 5, 7 und 11 Jahren bekamen Gesichter im rechten und linken Gesi.chtsfeldkurzzeitig gezeigt. Nach einem Interval1 wurden sie gefragt, ob ein Vergleichsgesicht mit demjenigen, das sie vorher sahen, identisch oder different war, Die Ergebnisse sprachen fur eine rech'cshemispharische tiberlegenheitin allen drei Altersstufen. Im Context mit theoretischen Erdrterungen iiberdie Entwicklung der funktionellen Lateralisierung des Gehirns wurden die Ergebnisse diskutlert.