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Intermanual differences in performing a visuoconstructional task
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Intermanual Differences in Performing a Visuoconstructional Task Shane Bush, PhD ABSTRACT. Bush S. Intermanual differences in performing a visuoconstructional task. Arch Phys Med Rehabil 2000;81: 1151-2. Objective: To examine intermanual differences in performing a clinical, visuoconstructional task. While many examiners have their hemiparetic patients complete visuospatial tasks with their nondominant hand, normative data have only been available based on dominant hand performance. This study sought to determine normal differences in intermanual visuoconstructional performance. Design: A group of individuals with no history of neurologic disorder completed a visuoconstruction task with their dominant and nondominant hands. Intermanual differences were compared. Setting: General metropolitan community. Participants: Forty-four individuals with no history of psychiatric, neurologic, visual, or motor impairment. Mean age was 29 years. Mean education level was 16 years. Main Outcome Measure: Free-drawn clock drawings. Results: The intermanual difference was not significant (t(43) ⫽ 1.95, p ⫽ .06). Ninety-three percent scored within normal limits with their nondominant hand. Conclusions: Use of the nondominant hand for clock drawing appears to be a reasonable alternative for those who are unable to use their dominant hand. Key Words: Visuospatial; Visuoconstructional; Clock drawing; Intermanual; Rehabilitation. r 2000 by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation
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ISUOSPATIAL SKILLS are frequently impaired following neurologic insults, and constructional tasks are often used in the assessment of visuospatial skills. Constructional performance combines spatial orientation, perceptual activity, motor skills, and executive functions, thus receiving contributions from diverse cerebral regions.1 Because of this complexity of neurocognitive skills, constructional tasks have been found to be sensitive to many different kinds of organic disabilities.2 Clock-drawing tasks are frequently used throughout the world for the assessment of visuoconstruction skills in patients who have had a brain injury.1 Although clock drawings are usually performed with the dominant hand, many individuals who have sustained brain injuries have impaired function of the dominant upper extremity. For example, hemiparesis is a frequent symptom following cerebrovascular accidents. While examiners may choose to
From The Head Injury Rehabilitation Unit at St. Johnland, Kings Park, NY. Accepted February 8, 2000. No commercial party having a direct financial interest in the results of the research supporting this article has or will confer a benefit upon the authors or upon any organization with which the authors are associated. Reprint requests to Shane Bush, PhD, The Head Injury Rehabilitation Unit at St. Johnland, 395 Sunken Meadow Rd, Kings Park, NY 11754. 0003-9993/00/8109-5965$3.00/0 doi:10.1053/apmr.2000.7169
have their patients complete visuoconstruction tasks with their nondominant hand, normative data are only available based on standard administration with the dominant hand. Without evidence related to nondominant hand efficiency with visuoconstruction skills, the examiner must interpret the findings without empirically based guidelines. For example, poor performance on a visuoconstruction task with the nondominant hand may reflect impaired visuoconstruction skills or natural intermanual differences. The purpose of this study was to investigate intermanual differences in clock-drawing performance in individuals without brain injuries to establish a baseline against which to compare the performances of those who have sustained brain injuries. Such information would provide examiners with preliminary evidence on which to base conclusions regarding visuoconstruction skills with the nondominant hand for those who are unable to complete the task with their dominant hand. A similar study that examined intermanual performances on the Trail Making Test3 found nonsignificant differences between hands.4 METHOD The subjects were 44 individuals without brain injuries from a general metropolitan community. Subjects ranged in age from 15 years to 45 years, with a mean age of 29 years. Their mean level of education was 16 years. Thirty-one of the subjects were women, and 13 were men. Thirty-eight of the subjects reported right-hand dominance, and 6 reported dominance of the left hand. None of the subjects had significant psychiatric or neurologic histories, and all subjects were free of visual and upper extremity motor impairment. Visuoconstruction skills were assessed with clock drawings. Subjects completed free-drawn clocks with each hand. Subjects were instructed to set the hands to the 11:10 position. Clock drawings were scored according to a 15-point system.1 This system provides for scoring according to four general categories: contour, numbers, hands, and center. Within these categories, points are given for acceptable representation of the figure and the interior details. Slight variability in the accuracy of line and detail placement is acceptable. In contrast, points are not given for gross spatial distortions or dysexecutive errors. Scoring is not based on speed of performance. The intermanual visuoconstructional difference was computed, and the significance of the difference was determined with a paired t test. Qualitative differences were also assessed. RESULTS Dominant-hand clock-drawing scores ranged from 13 to 15, with a mean of 14.61 (standard deviation, .69). Scores with the nondominant hand ranged from 12 to 15, with a mean of 14.39 (standard deviation, .87). The intermanual difference was not significant (t(43) ⫽ 1.95, p ⫽ .06). The percentages of subjects with given dominant-hand and nondominant-hand scores are listed in table 1. One subject (2%) scored 1 point below the range of published normative data with the dominant hand (40- to 49-yr age range).1 Two subjects (5%) scored 1 point below the Arch Phys Med Rehabil Vol 81, September 2000
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INTERMANUAL VISUOCONSTRUCTIONAL DIFFERENCES, Bush
Table 1: 11:10 Free-Drawn Clock: Percentage of Subjects With a Given Total Score Dominant Hand (n ⫽ 44)
Nondominant Hand (n ⫽ 44)
Score
%
Cumulative %
%
Cumulative %
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
11.36 15.91 72.73
11.36 27.27 100.00
4.55 9.09 27.27 59.09
4.55 13.64 40.91 100.00
normative data range with their nondominant hands (20- to 29-yr age range).1 Twenty-three percent of the subjects had a quantitative decline in performance of 1 or 2 points with their nondominant hand, but remained within the normative data range.1 The errors with the dominant hand and the percentage of subjects making each error included: contour overdrawn (16%), hands not in correct proportion (7%), numbers omitted or extra numbers added (5%), superfluous markings (5%), numbers not in correct position (2%), and absent or inaccurate center (2%). Errors with the nondominant hand included: contour overdrawn (27%), numbers omitted or extra numbers added (5%), no Arabic number representation (5%), superfluous markings (5%), absent or inaccurate center (5%), and paper rotated while drawing numbers (2%). Nine percent of the subjects demonstrated improved visuoconstruction skill with the nondominant hand. Twenty-seven percent of the subjects evidenced a mild degree of qualitative change in clock-drawing performance with the nondominant hand. These negative qualitative changes consisted of overdrawn details, slight tremor, rotation of numbers, superfluous marks, and distorted contour. In general, nondominant-hand drawings were slightly less efficient, such as
Arch Phys Med Rehabil Vol 81, September 2000
lines not being quite as straight or angles on numbers not being as sharp. DISCUSSION Clock drawings are frequently used in the assessment of visuoconstruction skills with individuals who have sustained injuries to the brain that resulted in hemiparesis of the dominant hand. The results of this study provide preliminary evidence that nondominant-hand performance on clock drawings is essentially comparable with the dominant hand. Although the difference between groups approached statistical significance, 95% of the subjects scored within the range of published normative data1 with their nondominant hands. This intermanual consistency supports the use of the nondominant hand for clock drawings in the assessment of visuoconstruction skills following brain injury when the dominant upper extremity is not functional. These findings are consistent with a previous study that found no significant difference between hands on the Trail Making Test.4 One limitation of this study may be the demographic composition of the subjects. The subjects used in this study are younger and have a higher level of education than many rehabilitation patients with hemiparesis. An extension of this study is underway to examine intermanual clock-drawing performance with rehabilitation patients who have not sustained brain injuries. Future studies may examine intermanual visuoconstruction skills with additional measures. CONCLUSION Although slight qualitative intermanual differences were evident on clock drawings, differences were not statistically significant. Therefore, the use of the nondominant hand for clock drawing appears to be a reasonable alternative for those who are unable to use their dominant hand. References 1. Freedman M, Leach L, Kaplan E, Winocur G, Shulman KI, Delis DC. Clock drawing: a neuropsychological analysis. New York: Oxford Univ Pr; 1994. 2. Lezak MD. Neuropsychological assessment. 3rd ed. New York: Oxford Univ Pr; 1995. 3. Partington JE, Leiter RG. Partington’s Pathway Test. Psychol Serv Cent Bull 1949;1:9-20. 4. Horowitz T, Caplan B. Dominant and nondominant hand performance on the trail making test [abstract]. Arch Clin Neuropsychol 1998;13:71-2.
Intermanual Differences in Performing a Visuoconstructional Task Shane Bush, PhD ABSTRACT. Bush S. Intermanual differences in performing a visuoconstructional task. Arch Phys Med Rehabil 2000;81: 1151-2. Objective: To examine intermanual differences in performing a clinical, visuoconstructional task. While many examiners have their hemiparetic patients complete visuospatial tasks with their nondominant hand, normative data have only been available based on dominant hand performance. This study sought to determine normal differences in intermanual visuoconstructional performance. Design: A group of individuals with no history of neurologic disorder completed a visuoconstruction task with their dominant and nondominant hands. Intermanual differences were compared. Setting: General metropolitan community. Participants: Forty-four individuals with no history of psychiatric, neurologic, visual, or motor impairment. Mean age was 29 years. Mean education level was 16 years. Main Outcome Measure: Free-drawn clock drawings. Results: The intermanual difference was not significant (t(43) ⫽ 1.95, p ⫽ .06). Ninety-three percent scored within normal limits with their nondominant hand. Conclusions: Use of the nondominant hand for clock drawing appears to be a reasonable alternative for those who are unable to use their dominant hand. Key Words: Visuospatial; Visuoconstructional; Clock drawing; Intermanual; Rehabilitation. r 2000 by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation
V
ISUOSPATIAL SKILLS are frequently impaired following neurologic insults, and constructional tasks are often used in the assessment of visuospatial skills. Constructional performance combines spatial orientation, perceptual activity, motor skills, and executive functions, thus receiving contributions from diverse cerebral regions.1 Because of this complexity of neurocognitive skills, constructional tasks have been found to be sensitive to many different kinds of organic disabilities.2 Clock-drawing tasks are frequently used throughout the world for the assessment of visuoconstruction skills in patients who have had a brain injury.1 Although clock drawings are usually performed with the dominant hand, many individuals who have sustained brain injuries have impaired function of the dominant upper extremity. For example, hemiparesis is a frequent symptom following cerebrovascular accidents. While examiners may choose to
From The Head Injury Rehabilitation Unit at St. Johnland, Kings Park, NY. Accepted February 8, 2000. No commercial party having a direct financial interest in the results of the research supporting this article has or will confer a benefit upon the authors or upon any organization with which the authors are associated. Reprint requests to Shane Bush, PhD, The Head Injury Rehabilitation Unit at St. Johnland, 395 Sunken Meadow Rd, Kings Park, NY 11754. 0003-9993/00/8109-5965$3.00/0 doi:10.1053/apmr.2000.7169
have their patients complete visuoconstruction tasks with their nondominant hand, normative data are only available based on standard administration with the dominant hand. Without evidence related to nondominant hand efficiency with visuoconstruction skills, the examiner must interpret the findings without empirically based guidelines. For example, poor performance on a visuoconstruction task with the nondominant hand may reflect impaired visuoconstruction skills or natural intermanual differences. The purpose of this study was to investigate intermanual differences in clock-drawing performance in individuals without brain injuries to establish a baseline against which to compare the performances of those who have sustained brain injuries. Such information would provide examiners with preliminary evidence on which to base conclusions regarding visuoconstruction skills with the nondominant hand for those who are unable to complete the task with their dominant hand. A similar study that examined intermanual performances on the Trail Making Test3 found nonsignificant differences between hands.4 METHOD The subjects were 44 individuals without brain injuries from a general metropolitan community. Subjects ranged in age from 15 years to 45 years, with a mean age of 29 years. Their mean level of education was 16 years. Thirty-one of the subjects were women, and 13 were men. Thirty-eight of the subjects reported right-hand dominance, and 6 reported dominance of the left hand. None of the subjects had significant psychiatric or neurologic histories, and all subjects were free of visual and upper extremity motor impairment. Visuoconstruction skills were assessed with clock drawings. Subjects completed free-drawn clocks with each hand. Subjects were instructed to set the hands to the 11:10 position. Clock drawings were scored according to a 15-point system.1 This system provides for scoring according to four general categories: contour, numbers, hands, and center. Within these categories, points are given for acceptable representation of the figure and the interior details. Slight variability in the accuracy of line and detail placement is acceptable. In contrast, points are not given for gross spatial distortions or dysexecutive errors. Scoring is not based on speed of performance. The intermanual visuoconstructional difference was computed, and the significance of the difference was determined with a paired t test. Qualitative differences were also assessed. RESULTS Dominant-hand clock-drawing scores ranged from 13 to 15, with a mean of 14.61 (standard deviation, .69). Scores with the nondominant hand ranged from 12 to 15, with a mean of 14.39 (standard deviation, .87). The intermanual difference was not significant (t(43) ⫽ 1.95, p ⫽ .06). The percentages of subjects with given dominant-hand and nondominant-hand scores are listed in table 1. One subject (2%) scored 1 point below the range of published normative data with the dominant hand (40- to 49-yr age range).1 Two subjects (5%) scored 1 point below the Arch Phys Med Rehabil Vol 81, September 2000
1152
INTERMANUAL VISUOCONSTRUCTIONAL DIFFERENCES, Bush
Table 1: 11:10 Free-Drawn Clock: Percentage of Subjects With a Given Total Score Dominant Hand (n ⫽ 44)
Nondominant Hand (n ⫽ 44)
Score
%
Cumulative %
%
Cumulative %
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
11.36 15.91 72.73
11.36 27.27 100.00
4.55 9.09 27.27 59.09
4.55 13.64 40.91 100.00
normative data range with their nondominant hands (20- to 29-yr age range).1 Twenty-three percent of the subjects had a quantitative decline in performance of 1 or 2 points with their nondominant hand, but remained within the normative data range.1 The errors with the dominant hand and the percentage of subjects making each error included: contour overdrawn (16%), hands not in correct proportion (7%), numbers omitted or extra numbers added (5%), superfluous markings (5%), numbers not in correct position (2%), and absent or inaccurate center (2%). Errors with the nondominant hand included: contour overdrawn (27%), numbers omitted or extra numbers added (5%), no Arabic number representation (5%), superfluous markings (5%), absent or inaccurate center (5%), and paper rotated while drawing numbers (2%). Nine percent of the subjects demonstrated improved visuoconstruction skill with the nondominant hand. Twenty-seven percent of the subjects evidenced a mild degree of qualitative change in clock-drawing performance with the nondominant hand. These negative qualitative changes consisted of overdrawn details, slight tremor, rotation of numbers, superfluous marks, and distorted contour. In general, nondominant-hand drawings were slightly less efficient, such as
Arch Phys Med Rehabil Vol 81, September 2000
lines not being quite as straight or angles on numbers not being as sharp. DISCUSSION Clock drawings are frequently used in the assessment of visuoconstruction skills with individuals who have sustained injuries to the brain that resulted in hemiparesis of the dominant hand. The results of this study provide preliminary evidence that nondominant-hand performance on clock drawings is essentially comparable with the dominant hand. Although the difference between groups approached statistical significance, 95% of the subjects scored within the range of published normative data1 with their nondominant hands. This intermanual consistency supports the use of the nondominant hand for clock drawings in the assessment of visuoconstruction skills following brain injury when the dominant upper extremity is not functional. These findings are consistent with a previous study that found no significant difference between hands on the Trail Making Test.4 One limitation of this study may be the demographic composition of the subjects. The subjects used in this study are younger and have a higher level of education than many rehabilitation patients with hemiparesis. An extension of this study is underway to examine intermanual clock-drawing performance with rehabilitation patients who have not sustained brain injuries. Future studies may examine intermanual visuoconstruction skills with additional measures. CONCLUSION Although slight qualitative intermanual differences were evident on clock drawings, differences were not statistically significant. Therefore, the use of the nondominant hand for clock drawing appears to be a reasonable alternative for those who are unable to use their dominant hand. References 1. Freedman M, Leach L, Kaplan E, Winocur G, Shulman KI, Delis DC. Clock drawing: a neuropsychological analysis. New York: Oxford Univ Pr; 1994. 2. Lezak MD. Neuropsychological assessment. 3rd ed. New York: Oxford Univ Pr; 1995. 3. Partington JE, Leiter RG. Partington’s Pathway Test. Psychol Serv Cent Bull 1949;1:9-20. 4. Horowitz T, Caplan B. Dominant and nondominant hand performance on the trail making test [abstract]. Arch Clin Neuropsychol 1998;13:71-2.