EDITOR'S COMMENT: The following article will be of interest to readers investigating the presence of learning disabilities in other specific populations. One intervention often employed in the field of learning disabilities, cognitive behavioral modification, appeared successful with the children in this study.—JLW
Comparison of Visual-Spatial Performance Strategy Training in Children with Turner Syndrome and Learning Disabilities Janet K. Williams, Lynn Charles Richman, and Donald B. Yarbrough
This study examined the effects of a verbal mediation strategy on three groups of subjects who had visual-spatial deficits. Thirteen females with Turner syndrome, 13 females with nonverbal learning disabilities, and 14 males with nonverbal learning disabilities, who ranged in age from 7 to 14 years, were taught via a cognitive behavioral modification approach to verbally mediate a spatial matching task. Pretest and posttest performance differences on parallel forms of a visual-spatial orientation task were examined. All three groups showed significant improvement in visual-spatial task performance after the training. There were no significant differences in the degree of improvement among the three groups. The results suggest that children with Turner syndrome may benefit from problem-solving strategy training in a manner similar to children with nonverbal learning disabilities.
I
ndividuals with Turner syndrome are at increased risk for deficits in nonverbal (visual-spatial) functioning, although they typically have average to above-average verbal skills (Downey et al., 1991; Garron, 1977; Gordon & Galatzer, 1980; Netley, 1983; Robinson, Bender, Borelli, Puck, & Salbenblatt, 1983). More specifically, children with Turner syndrome have been found to show deficits on spatial rotation tasks under both timed and untimed conditions (Bender, Puck, Salbenblatt, & Robinson, 1990; Rovet & Netley, 1980, 1982). Although the finding of visual-spatial deficits in females with Turner syndrome is con-
sistently reported by numerous investigators, the possibility that individuals with Turner syndrome might benefit from interventions utilized with children with learning disabilities has not been investigated. The intent of the present study was to examine the nature of strategy training on visualspatial deficits in children with Turner syndrome and to see if the outcomes were different or similar to those in children with nonverbal learning disabilities (NLD). Approximately 50 years ago, Henry Turner (1938) described a disorder in females in which individuals had sexual infantilism, webbed neck, and JOURNAL OF LEARNING DISABILITIES Downloaded from ldx.sagepub.com Purdue University on1992 May 24, 2015 VOLUME 25, NUMBERat10, DECEMBER
PAGES 658-664
elbow deformities. Turner syndrome is a disorder in which females are missing all or a part of one X chromosome. The most consistent physical features of Turner syndrome are small stature and gonadal dysgenesis (absence of ovaries). Congenital anomalies may also be present in the heart or kidneys, and individuals with this disorder may be more likely to have high-frequency hearing loss (Jones, 1988). It was first believed that mental retardation was commonly associated with Turner syndrome (Haddad & Wilkins, 1959); however, when intellectual testing was uniformly conducted on study subjects, and when other explanations for mental retardation were sought, increased frequency of mental retardation with Turner syndrome was not found (Sybert, Reed, & Hall, 1980). Results of intelligence testing also revealed a pattern of decreased nonverbal skills and average verbal skills (Buckley, 1971; Downey et al., 1991; Garron, 1977). In addition to the finding of deficits in nonverbal areas, there is some evidence regarding deficits in verbal and visual memory. Deficits
VOLUME 25, NUMBER 10, DECEMBER 1992
on the Digit Span subtest from the WISC-R were reported in individuals with Turner syndrome by several investigators (Garron, 1977; Silbert, Wolff, & Lillienthal, 1977; Waber, 1979). Memory deficits were also reported in investigations measuring long-term memory (Pennington, Heaton, Karzmark, & Pendleton, 1985) and visual memory (LaHood & Bacon, 1985). Waber reported deficits in both verbal and visual memory areas, and deficits in verbal memory and attention were reported by McGlone (1985) and McCauley, Ito, Kay, and Treder (1987). The cognitive deficits most frequently described in Turner syndrome resemble a subtype of learning disabilities (LD) in which deficits in nonverbal skills are present. Although specific approaches to the study of LD subtypes vary among investigators, outcomes of subtyping studies consistently include a group of children with deficits in nonverbal skills, such as visual-spatial orientation or visualmotor functions (Denkla & Rudel, 1976; Mattis, French, & Rapin, 1975; Rourke & Finlayson, 1978; Satz, Rardin, & Ross, 1971). Children with deficits in nonverbal skills have been found to be more likely to make errors in arithmetic, such as misaligning numbers in columns and misreading the mathematical sign (Rourke & Finlayson, 1978). Children with Performance Intelligence (PIQ) < Verbal Intelligence (VIQ) discrepancies have been shown to have poor performance on complex psychomotor measures and tactile-perceptual skills (Rourke & Strang, 1978). The accumulation of data on children with nonverbal LD led Rourke (1989) to summarize these findings as characteristic of a nonverbal learning disabilities syndrome. Rourke reported that these children's assets are principally their abilities to deal with auditory information and auditory perception. Reception, storage, and associations of verbal information are generally unaffected; however, content and pragmatics of language use are likely to be deficient. Thus, deficits in
academic areas are not necessarily confined to arithmetic and graphomotor skills, but may also encompass reading comprehension. Cognitive deficits also may be manifested in school subjects involving problem solving and concept formation, such as science (Rourke, 1989). Features of the NLD syndrome are reported to be present in children with various neurological disorders. Children with neurofibromatosis are more likely than other children to have a form of NLD (Eliason, 1986). Other conditions with which children are more likely to display signs of NLD are moderate to severe head injuries, hydrocephalus, congenital absence of the corpus callosum, loss of tissue from the right cerebral hemisphere, and survivors of childhood cancers who underwent large doses of x-irradiation for a prolonged period of time (Rourke, 1989). Interventions recommended to address the multiple problems experienced by children with NLD focus on utilizing their relatively stronger verbal skills as a means by which to analyze and understand their nonverbal experiences (Ozols & Rourke, 1985; Rourke, 1989; Wiig & Semel, 1976). A strategy that has been successfully used with some children with learning disabilities is cognitive behavioral modification (CBM) (Meichenbaum, 1985). CBM is aimed at enhancing strategic thinking processes associated with academic skills by utilizing verbal skills in planning and executing a learning task. It places emphasis on development of schemata in learning new information, teaching necessary thinking processes, and planning for generalization of the strategy (Bos, 1988). The cognitive mediation approach is designed to teach a child to engage in mediating responses that exemplify a general strategy for controlling behavior under various circumstances. It includes making verbal statements to oneself that prompt, direct, or maintain behavior (Meichenbaum, 1985). CBM has been found to be effective in improving ability to inhibit impul-
Downloaded from ldx.sagepub.com at Purdue University on May 24, 2015
659 sivity (Camp, Blom, Hebert, & vanDporninck, 1977; Meichenbaum & Goodman, 1971) and to improve academic tasks relying on verbal skills, such as reading (Malamuth, 1979; Wong & Sawatsky, 1984). Investigations of strategy training to improve nonverbal skills in children with LD have not been reported. However, several investigators have suggested that children with LD are deficient in their use of effective and task-appropriate strategies (Ceci & Baker, 1989; Swanson, 1984; Torgesen, 1977, 1980; Voelker, Carter, Sprague, Gdowski, & Lacher, 1989). Because cognitive patterns in individuals with Turner syndrome appear to be similar to those in children with NLD, it was decided that comparison of children with Turner syndrome to children with NLD could increase understanding of cognitive aspects of this disorder, and the usefulness of a particular strategy training approach. Deficits in nonverbal cognitive skills have been described as being gender specific in the general population, with nonverbal deficits more common in females and verbal deficits more common in males (Maccoby & Jacklin, 1974). This finding has not been uniformly endorsed in the general population (Petersen & Wittig, 1979). A pattern of stronger visual-spatial skills in males with LD and stronger visualmotor and verbal conceptualization skills in females with LD was reported in a study of college-age students (Vogel & Walsh, 1987). LD subtypes were not reported in these subjects. When subtype of LD was controlled in a sample of school-age children, no gender differences in cognitive patterns were found (Gilger, Eliason, & Richman, 1989). An absence of gender differences in the NLD population has also been reported by Rourke (1989). The role of gender in influencing cognitive abilities in individuals with Turner syndrome is not clear. Phenotypic sex in these individuals is uniformly female; however, the chromosomal sex is not identical to a female gender assignment (two X chro-
660
JOURNAL OF LEARNING DISABILITIES
mosomes). Individuals with Turner syndrome have only one complete X chromosome; some individuals may have a second incomplete X chromosome, and some have two types of cells: some with one X only and some with two X chromosomes. In contrast, males have one X chromosome as well as a Y chromosome. In previous studies of individuals with Turner syndrome, contrast or control groups have been composed of female subjects. Because the impact of genetic and social factors on cognitive abilities is not well understood, comparison groups chosen for this study included a group of females and a group of males with nonverbal LD. The purpose of this study was to determine if it was possible to alter performance on a visualspatial task for children with visualspatial deficits, and if the nature of the outcome of strategy training in children with Turner syndrome was similar to or different from that in children with NLD.
Method Subjects The subjects were 40 children selected from clients of the Pediatric Genetics, Endocrine, and Learning Disabilities Clinics at a university pediatric clinic. All subjects were members of white, middle class, nonminority families, and were residents of rural or urban midwestern communities. All subjects with LD were diagnosed as having visual-spatial deficits and LD according to both the State Department of Public Instruction intelligenceacademic achievement discrepancy criteria (Cone & Wilson, 1981) and the Learning Disabilities Clinic neuropsychological subtyping criteria (Eliason & Richman, 1988). These children functioned at least one grade level below peers in reading or arithmetic and achieved test scores on tests of nonverbal abilities that were greater than 1 standard deviation from the mean. Subjects with NLD were defined as meeting the above criteria for LD and
scoring at least 1 SD below average on both a visual-motor task and a visualspatial perception task. The visualmotor task was the Bender Visual Motor Gestalt Test (Koppitz, 1963), and the visual-spatial perception task was the Judgment of Line Orientation test (Benton, Hamsher, Varney, & Spreen, 1983). Those with Turner syndrome had had previous chromosomal confirmation of the diagnosis. A discussion of subjects with Turner syndrome was presented in an earlier publication (Williams, 1992). There were three groups in the study: individuals with Turner syndrome (n = 13), females with NLD (n = 13), and males with NLD (n = 14). Ages of subjects ranged from 7 to 14 years. The mean age in months and standard deviations for each group were as follows: Turner syndrome, M=115.3 (SD=25.9); LD female, M = 119.4 (SD = 26.4); and LD male, M = 124.9 (SD = 19.9). The mean VIQ and standard deviations for each group were as follows: Turner syndrome, M=100.5 (SD = 12.8); LD female, M= 100.3 (SD=5.6); and LD male, M=95.0 (SD = 8.7). Criteria for inclusion were (a) VIQ scores of at least 80, (b) scores on the visual-spatial perception test (Judgment of Line Orientation) and the visual-motor task (Bender Visual Motor Gestalt Test) 1 standard deviation or greater below the mean, and (c) no primary emotional or behavioral disorder.
Instruments Visual-spatial perception was evaluated on pretests and posttests using the Judgment of Line Orientation (JLO). This assessment tool was developed from Benton's investigations into the effects of right-hemisphere lesions on spatial orientation skills. During administration, the child was shown an array of lines varying from the horizontal in 18-degree increments. A number, moving in ascending order from 1 to 11, appeared at the end of each line. Once the child was familiar with the concept of each line having a
Downloaded from ldx.sagepub.com at Purdue University on May 24, 2015
numbered identity, he or she was shown another page displaying two lines from the entire pattern, but without numbers. The task for the child was to correctly identify what the number for each line would be. The entire test included 30 items, with 5 additional items appearing at the beginning for use as practice trials. Split-half reliability was established in a sample of 221 children ranging in age from 7 to 14 years (Lindgren & Benton, 1980). Two forms, Form H and Form V, were available for the JLO. Split-half reliability of Form H was .94 and of Form V was .89. Test-retest reliability was also assessed in a sample of 37 individuals. The mean scores for the first and second administration were almost identical (23.1 and 23.5, respectively), indicating the absence of a systematic practice effect (Benton et al., 1983). In the present study, each subject received Form H and Form V of the JLO as an assessment of visual-spatial perception. To avoid potential order effect, the order in which the forms were administered was alternated so that one subject received Form H as a pretest and Form V as a posttest, and the next subject received the tests in the opposite order. To avoid subject fatigue, only the odd-numbered items were administered at the pretest and posttest evaluations. Although there were repetitions of approximately half of the items on the two forms of the test, no systematic practice effect was found on the posttest.
Procedure Each child was tested individually by one of three examiners during a routine outpatient visit to the Pediatric Clinics. The JLO test was administered to each child for pretest and posttest assessments of visual-spatial perception. Cognitive behavior modification instruction was given immediately following the administration of the JLO pretest. The dialogue was adapted from that used by Camp et al. (1977) and Meichenbaum and Goodman (1971). The training session required
661
VOLUME 25, NUMBER 10, DECEMBER 1992
approximately 20 minutes to complete. The examiner began the dialogue by saying the following: That test with the lines can be a tough one to do. I am going to show you a way that will help you do a better job on that kind of task. When I do those, it helps me when I talk to myself while I work. I am going to show you how this is done and then you will have a chance to practice it. Training materials involved identification of an incomplete design. The items were modified from the Benton Visual Form Discrimination test (VFD) (Benton, Varney, & Hamsher, 1978). One design page from the Benton VFD was shown to the subject. Five incomplete designs for the training intervention were developed by tracing a set of two lines per page from the complete design. The training task required the subject to identify lines that were part of the complete design. Both the individual lines and the complete design were shown to the subject at each trial. This procedure was identical to the one followed in the administration of the JLO. In the first part, the examiner demonstrated matching a partial design with the entire design while talking to himself or herself out loud and stating what the examiner was supposed to do. In the second part of the instruction, the subject performed a similar task on another sample under the verbal direction of the examiner. In the third part, the subject performed a task while instructing himself or herself out loud. In the next part, the subject whispered instructions to himself or herself while performing the task and, in the last part, the subject performed the task while guiding the performance via private speech. Throughout the instruction, the examiner gave verbal cues to the subject in assisting him or her to engage in self-talk while performing the instructional task. All subjects showed ability to carry out the CBM, based on successful completion of training items. Following comple-
tion of the CBM instruction, the subjects were given the JLO as a posttest.
Analysis A mixed-model analysis of variance was used to analyze the effects of the four independent variables (group, time, order, and form) in the dependent variable (scores on the JLO). This design permitted counterbalancing of the test forms. Each of the three subject groups was subdivided into approximately equal-sized subgroups. One subgroup received Form H followed by Form V, and the other subgroup received Form V followed by Form H.
Results The means and standard deviations for the pretest and posttest visualspatial tests for the three groups are presented in Table 1. Results of pretest and posttest scores for each group are plotted in Figure 1. A four-way mixed model of analysis of variance was performed to evaluate two between-subject differences (group, order) and two within-subject differences (time, form). Group refers
to the three groups (Turner syndrome, females with LD, and males with LD); order refers to whether subjects received Form H or Form V first or second; time refers to Time 1 (pretest) and Time 2 (posttest); and form refers to the parallel tests Form H and Form V. The analyses indicated no significant main effect for Group, F(2,34)=2.21, p> .05, indicating no overall differences in the total visual-spatial scores for the three groups. Thus, each group performed in a similar manner on this intervention. There also was no significant difference for order in which the parallel forms of the test were administered, F(l,34) = 1.06, p> .05. This suggests that there was no confounding of the effect of strategy training by order of which test was administered first. Furthermore, no significant Group x Order interaction effect was found, F(2,34) = .34, p > .05. There was no significant within-subject interaction effect for Group x Form, F(2,34) = 1.38, p> .05. There was no significant main effect for Form, F(l,34) = .82, p>.05, indicating that the two parallel forms of the JLO showed good equality for these subjects. A significant main effect for time, F(l,34)=46.33, p
Comparison of Visual-Spatial Performance Strategy Training in Children with Turner Syndrome and Learning Disabilities Janet K. Williams, Lynn Charles Richman, and Donald B. Yarbrough
This study examined the effects of a verbal mediation strategy on three groups of subjects who had visual-spatial deficits. Thirteen females with Turner syndrome, 13 females with nonverbal learning disabilities, and 14 males with nonverbal learning disabilities, who ranged in age from 7 to 14 years, were taught via a cognitive behavioral modification approach to verbally mediate a spatial matching task. Pretest and posttest performance differences on parallel forms of a visual-spatial orientation task were examined. All three groups showed significant improvement in visual-spatial task performance after the training. There were no significant differences in the degree of improvement among the three groups. The results suggest that children with Turner syndrome may benefit from problem-solving strategy training in a manner similar to children with nonverbal learning disabilities.
I
ndividuals with Turner syndrome are at increased risk for deficits in nonverbal (visual-spatial) functioning, although they typically have average to above-average verbal skills (Downey et al., 1991; Garron, 1977; Gordon & Galatzer, 1980; Netley, 1983; Robinson, Bender, Borelli, Puck, & Salbenblatt, 1983). More specifically, children with Turner syndrome have been found to show deficits on spatial rotation tasks under both timed and untimed conditions (Bender, Puck, Salbenblatt, & Robinson, 1990; Rovet & Netley, 1980, 1982). Although the finding of visual-spatial deficits in females with Turner syndrome is con-
sistently reported by numerous investigators, the possibility that individuals with Turner syndrome might benefit from interventions utilized with children with learning disabilities has not been investigated. The intent of the present study was to examine the nature of strategy training on visualspatial deficits in children with Turner syndrome and to see if the outcomes were different or similar to those in children with nonverbal learning disabilities (NLD). Approximately 50 years ago, Henry Turner (1938) described a disorder in females in which individuals had sexual infantilism, webbed neck, and JOURNAL OF LEARNING DISABILITIES Downloaded from ldx.sagepub.com Purdue University on1992 May 24, 2015 VOLUME 25, NUMBERat10, DECEMBER
PAGES 658-664
elbow deformities. Turner syndrome is a disorder in which females are missing all or a part of one X chromosome. The most consistent physical features of Turner syndrome are small stature and gonadal dysgenesis (absence of ovaries). Congenital anomalies may also be present in the heart or kidneys, and individuals with this disorder may be more likely to have high-frequency hearing loss (Jones, 1988). It was first believed that mental retardation was commonly associated with Turner syndrome (Haddad & Wilkins, 1959); however, when intellectual testing was uniformly conducted on study subjects, and when other explanations for mental retardation were sought, increased frequency of mental retardation with Turner syndrome was not found (Sybert, Reed, & Hall, 1980). Results of intelligence testing also revealed a pattern of decreased nonverbal skills and average verbal skills (Buckley, 1971; Downey et al., 1991; Garron, 1977). In addition to the finding of deficits in nonverbal areas, there is some evidence regarding deficits in verbal and visual memory. Deficits
VOLUME 25, NUMBER 10, DECEMBER 1992
on the Digit Span subtest from the WISC-R were reported in individuals with Turner syndrome by several investigators (Garron, 1977; Silbert, Wolff, & Lillienthal, 1977; Waber, 1979). Memory deficits were also reported in investigations measuring long-term memory (Pennington, Heaton, Karzmark, & Pendleton, 1985) and visual memory (LaHood & Bacon, 1985). Waber reported deficits in both verbal and visual memory areas, and deficits in verbal memory and attention were reported by McGlone (1985) and McCauley, Ito, Kay, and Treder (1987). The cognitive deficits most frequently described in Turner syndrome resemble a subtype of learning disabilities (LD) in which deficits in nonverbal skills are present. Although specific approaches to the study of LD subtypes vary among investigators, outcomes of subtyping studies consistently include a group of children with deficits in nonverbal skills, such as visual-spatial orientation or visualmotor functions (Denkla & Rudel, 1976; Mattis, French, & Rapin, 1975; Rourke & Finlayson, 1978; Satz, Rardin, & Ross, 1971). Children with deficits in nonverbal skills have been found to be more likely to make errors in arithmetic, such as misaligning numbers in columns and misreading the mathematical sign (Rourke & Finlayson, 1978). Children with Performance Intelligence (PIQ) < Verbal Intelligence (VIQ) discrepancies have been shown to have poor performance on complex psychomotor measures and tactile-perceptual skills (Rourke & Strang, 1978). The accumulation of data on children with nonverbal LD led Rourke (1989) to summarize these findings as characteristic of a nonverbal learning disabilities syndrome. Rourke reported that these children's assets are principally their abilities to deal with auditory information and auditory perception. Reception, storage, and associations of verbal information are generally unaffected; however, content and pragmatics of language use are likely to be deficient. Thus, deficits in
academic areas are not necessarily confined to arithmetic and graphomotor skills, but may also encompass reading comprehension. Cognitive deficits also may be manifested in school subjects involving problem solving and concept formation, such as science (Rourke, 1989). Features of the NLD syndrome are reported to be present in children with various neurological disorders. Children with neurofibromatosis are more likely than other children to have a form of NLD (Eliason, 1986). Other conditions with which children are more likely to display signs of NLD are moderate to severe head injuries, hydrocephalus, congenital absence of the corpus callosum, loss of tissue from the right cerebral hemisphere, and survivors of childhood cancers who underwent large doses of x-irradiation for a prolonged period of time (Rourke, 1989). Interventions recommended to address the multiple problems experienced by children with NLD focus on utilizing their relatively stronger verbal skills as a means by which to analyze and understand their nonverbal experiences (Ozols & Rourke, 1985; Rourke, 1989; Wiig & Semel, 1976). A strategy that has been successfully used with some children with learning disabilities is cognitive behavioral modification (CBM) (Meichenbaum, 1985). CBM is aimed at enhancing strategic thinking processes associated with academic skills by utilizing verbal skills in planning and executing a learning task. It places emphasis on development of schemata in learning new information, teaching necessary thinking processes, and planning for generalization of the strategy (Bos, 1988). The cognitive mediation approach is designed to teach a child to engage in mediating responses that exemplify a general strategy for controlling behavior under various circumstances. It includes making verbal statements to oneself that prompt, direct, or maintain behavior (Meichenbaum, 1985). CBM has been found to be effective in improving ability to inhibit impul-
Downloaded from ldx.sagepub.com at Purdue University on May 24, 2015
659 sivity (Camp, Blom, Hebert, & vanDporninck, 1977; Meichenbaum & Goodman, 1971) and to improve academic tasks relying on verbal skills, such as reading (Malamuth, 1979; Wong & Sawatsky, 1984). Investigations of strategy training to improve nonverbal skills in children with LD have not been reported. However, several investigators have suggested that children with LD are deficient in their use of effective and task-appropriate strategies (Ceci & Baker, 1989; Swanson, 1984; Torgesen, 1977, 1980; Voelker, Carter, Sprague, Gdowski, & Lacher, 1989). Because cognitive patterns in individuals with Turner syndrome appear to be similar to those in children with NLD, it was decided that comparison of children with Turner syndrome to children with NLD could increase understanding of cognitive aspects of this disorder, and the usefulness of a particular strategy training approach. Deficits in nonverbal cognitive skills have been described as being gender specific in the general population, with nonverbal deficits more common in females and verbal deficits more common in males (Maccoby & Jacklin, 1974). This finding has not been uniformly endorsed in the general population (Petersen & Wittig, 1979). A pattern of stronger visual-spatial skills in males with LD and stronger visualmotor and verbal conceptualization skills in females with LD was reported in a study of college-age students (Vogel & Walsh, 1987). LD subtypes were not reported in these subjects. When subtype of LD was controlled in a sample of school-age children, no gender differences in cognitive patterns were found (Gilger, Eliason, & Richman, 1989). An absence of gender differences in the NLD population has also been reported by Rourke (1989). The role of gender in influencing cognitive abilities in individuals with Turner syndrome is not clear. Phenotypic sex in these individuals is uniformly female; however, the chromosomal sex is not identical to a female gender assignment (two X chro-
660
JOURNAL OF LEARNING DISABILITIES
mosomes). Individuals with Turner syndrome have only one complete X chromosome; some individuals may have a second incomplete X chromosome, and some have two types of cells: some with one X only and some with two X chromosomes. In contrast, males have one X chromosome as well as a Y chromosome. In previous studies of individuals with Turner syndrome, contrast or control groups have been composed of female subjects. Because the impact of genetic and social factors on cognitive abilities is not well understood, comparison groups chosen for this study included a group of females and a group of males with nonverbal LD. The purpose of this study was to determine if it was possible to alter performance on a visualspatial task for children with visualspatial deficits, and if the nature of the outcome of strategy training in children with Turner syndrome was similar to or different from that in children with NLD.
Method Subjects The subjects were 40 children selected from clients of the Pediatric Genetics, Endocrine, and Learning Disabilities Clinics at a university pediatric clinic. All subjects were members of white, middle class, nonminority families, and were residents of rural or urban midwestern communities. All subjects with LD were diagnosed as having visual-spatial deficits and LD according to both the State Department of Public Instruction intelligenceacademic achievement discrepancy criteria (Cone & Wilson, 1981) and the Learning Disabilities Clinic neuropsychological subtyping criteria (Eliason & Richman, 1988). These children functioned at least one grade level below peers in reading or arithmetic and achieved test scores on tests of nonverbal abilities that were greater than 1 standard deviation from the mean. Subjects with NLD were defined as meeting the above criteria for LD and
scoring at least 1 SD below average on both a visual-motor task and a visualspatial perception task. The visualmotor task was the Bender Visual Motor Gestalt Test (Koppitz, 1963), and the visual-spatial perception task was the Judgment of Line Orientation test (Benton, Hamsher, Varney, & Spreen, 1983). Those with Turner syndrome had had previous chromosomal confirmation of the diagnosis. A discussion of subjects with Turner syndrome was presented in an earlier publication (Williams, 1992). There were three groups in the study: individuals with Turner syndrome (n = 13), females with NLD (n = 13), and males with NLD (n = 14). Ages of subjects ranged from 7 to 14 years. The mean age in months and standard deviations for each group were as follows: Turner syndrome, M=115.3 (SD=25.9); LD female, M = 119.4 (SD = 26.4); and LD male, M = 124.9 (SD = 19.9). The mean VIQ and standard deviations for each group were as follows: Turner syndrome, M=100.5 (SD = 12.8); LD female, M= 100.3 (SD=5.6); and LD male, M=95.0 (SD = 8.7). Criteria for inclusion were (a) VIQ scores of at least 80, (b) scores on the visual-spatial perception test (Judgment of Line Orientation) and the visual-motor task (Bender Visual Motor Gestalt Test) 1 standard deviation or greater below the mean, and (c) no primary emotional or behavioral disorder.
Instruments Visual-spatial perception was evaluated on pretests and posttests using the Judgment of Line Orientation (JLO). This assessment tool was developed from Benton's investigations into the effects of right-hemisphere lesions on spatial orientation skills. During administration, the child was shown an array of lines varying from the horizontal in 18-degree increments. A number, moving in ascending order from 1 to 11, appeared at the end of each line. Once the child was familiar with the concept of each line having a
Downloaded from ldx.sagepub.com at Purdue University on May 24, 2015
numbered identity, he or she was shown another page displaying two lines from the entire pattern, but without numbers. The task for the child was to correctly identify what the number for each line would be. The entire test included 30 items, with 5 additional items appearing at the beginning for use as practice trials. Split-half reliability was established in a sample of 221 children ranging in age from 7 to 14 years (Lindgren & Benton, 1980). Two forms, Form H and Form V, were available for the JLO. Split-half reliability of Form H was .94 and of Form V was .89. Test-retest reliability was also assessed in a sample of 37 individuals. The mean scores for the first and second administration were almost identical (23.1 and 23.5, respectively), indicating the absence of a systematic practice effect (Benton et al., 1983). In the present study, each subject received Form H and Form V of the JLO as an assessment of visual-spatial perception. To avoid potential order effect, the order in which the forms were administered was alternated so that one subject received Form H as a pretest and Form V as a posttest, and the next subject received the tests in the opposite order. To avoid subject fatigue, only the odd-numbered items were administered at the pretest and posttest evaluations. Although there were repetitions of approximately half of the items on the two forms of the test, no systematic practice effect was found on the posttest.
Procedure Each child was tested individually by one of three examiners during a routine outpatient visit to the Pediatric Clinics. The JLO test was administered to each child for pretest and posttest assessments of visual-spatial perception. Cognitive behavior modification instruction was given immediately following the administration of the JLO pretest. The dialogue was adapted from that used by Camp et al. (1977) and Meichenbaum and Goodman (1971). The training session required
661
VOLUME 25, NUMBER 10, DECEMBER 1992
approximately 20 minutes to complete. The examiner began the dialogue by saying the following: That test with the lines can be a tough one to do. I am going to show you a way that will help you do a better job on that kind of task. When I do those, it helps me when I talk to myself while I work. I am going to show you how this is done and then you will have a chance to practice it. Training materials involved identification of an incomplete design. The items were modified from the Benton Visual Form Discrimination test (VFD) (Benton, Varney, & Hamsher, 1978). One design page from the Benton VFD was shown to the subject. Five incomplete designs for the training intervention were developed by tracing a set of two lines per page from the complete design. The training task required the subject to identify lines that were part of the complete design. Both the individual lines and the complete design were shown to the subject at each trial. This procedure was identical to the one followed in the administration of the JLO. In the first part, the examiner demonstrated matching a partial design with the entire design while talking to himself or herself out loud and stating what the examiner was supposed to do. In the second part of the instruction, the subject performed a similar task on another sample under the verbal direction of the examiner. In the third part, the subject performed a task while instructing himself or herself out loud. In the next part, the subject whispered instructions to himself or herself while performing the task and, in the last part, the subject performed the task while guiding the performance via private speech. Throughout the instruction, the examiner gave verbal cues to the subject in assisting him or her to engage in self-talk while performing the instructional task. All subjects showed ability to carry out the CBM, based on successful completion of training items. Following comple-
tion of the CBM instruction, the subjects were given the JLO as a posttest.
Analysis A mixed-model analysis of variance was used to analyze the effects of the four independent variables (group, time, order, and form) in the dependent variable (scores on the JLO). This design permitted counterbalancing of the test forms. Each of the three subject groups was subdivided into approximately equal-sized subgroups. One subgroup received Form H followed by Form V, and the other subgroup received Form V followed by Form H.
Results The means and standard deviations for the pretest and posttest visualspatial tests for the three groups are presented in Table 1. Results of pretest and posttest scores for each group are plotted in Figure 1. A four-way mixed model of analysis of variance was performed to evaluate two between-subject differences (group, order) and two within-subject differences (time, form). Group refers
to the three groups (Turner syndrome, females with LD, and males with LD); order refers to whether subjects received Form H or Form V first or second; time refers to Time 1 (pretest) and Time 2 (posttest); and form refers to the parallel tests Form H and Form V. The analyses indicated no significant main effect for Group, F(2,34)=2.21, p> .05, indicating no overall differences in the total visual-spatial scores for the three groups. Thus, each group performed in a similar manner on this intervention. There also was no significant difference for order in which the parallel forms of the test were administered, F(l,34) = 1.06, p> .05. This suggests that there was no confounding of the effect of strategy training by order of which test was administered first. Furthermore, no significant Group x Order interaction effect was found, F(2,34) = .34, p > .05. There was no significant within-subject interaction effect for Group x Form, F(2,34) = 1.38, p> .05. There was no significant main effect for Form, F(l,34) = .82, p>.05, indicating that the two parallel forms of the JLO showed good equality for these subjects. A significant main effect for time, F(l,34)=46.33, p
