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This study examined the ability of executive functions (EF) to account for the relationship between Attention Deficit Hyperactivity Disorder (ADHD) status and social adjustment as indexed by parent and teacher report and by performance on a standardized observational "chat room" task. Children with the Combined subtype (ADHD-C; n = 23), the Primarily Inattentive Subtype (ADHD-I; n = 33), and non-ADHD controls (n = 36) participated. EF did not mediate the relationship between ADHD status and parent or teacher report of social adjustment. EF accounted for about 40-50% of the variance between ADHD status and the ability of children to detect subtle verbal cues as well as memory for the conversation in the chat room task, but did not mediate the relationship between ADHD and the number of prosocial, hostile, or on-topic statements that were made. Results are consistent with other recent reports, and suggest that the role of EF deficits in the production of social skill deficits in ADHD may not be as prominent as is typically assumed. The implications for the development of intervention programs designed to target core cognitive etiologic factors are discussed.

Objectives: The purpose of this work was to determine whether visual impairment caused by toxoplasmic chorioretinitis is associated with impaired performance of specific tasks on standardized tests of cognitive function. If so, then we worked to determine whether there are patterns in these difficulties that provide a logical basis for development of measures of cognitive function independent of visual impairment and compensatory intervention strategies to facilitate learning for such children., Methods: Sixty-four children with congenital toxoplasmosis with intelligence quotient scores > or = 50 and visual acuity sufficient to cooperate with all of the intelligence quotient subscales had assessments of their vision, appearance of their retinas, and cognitive testing performed between 3.5 and 5 years of age. These evaluations took place between 1981 and 1998 as part of a longitudinal study to determine outcome of congenital toxoplasmosis. Children were evaluated at 3.5 or 5 (37 children) or both 3.5 and 5 (27 children) years of age. Cognitive function was measured using the Wechsler Preschool and Primary Scale of Intelligence-Revised. Wechsler Preschool and Primary Scale of Intelligence-Revised scale scores were compared for children grouped as those children who had normal visual acuity in their best eye (group 1), and those who had impaired vision in their best eye (acuity < 20/40) because of macular disease (group 2). Demographic characteristics were compared for children in the 2 groups. Test scores were compared between groups using all of the 3.5-year-old visits, all of the 5-year-old visits, and using each child's "last" visit (ie, using the 5-year-old test results when a child was tested at both 3.5 and 5 years of age or only at 5 years, otherwise using the 3.5-year-old test results). The results were similar and, therefore, only the results from the last analysis are reported here., Results: There were 48 children with normal visual acuity in their best eye (group 1) and 16 children with impaired vision because of macular involvement in their best eye (group 2). Ethnicity and socioeconomic scores were similar. There was a significantly greater proportion of males in group 2 compared with group 1 (81% vs 46%). There was no significant diminution in Wechsler Preschool and Primary Scale of Intelligence-Revised test scores between 3.5 and 5 years of age for the 27 children tested at both of these ages. Verbal intelligence quotient, performance intelligence quotient, full-scale intelligence quotient scores, and all of the scaled scores except arithmetic and block design were significantly lower for children in group 2 compared with group 1. The majority of the differences remained statistically significant or borderline significant after adjusting for gender. However, the difference in overall verbal scores does not remain statistically significant. Mean +/- SD verbal (98 +/- 20) and performance (95 +/- 17) intelligence quotients were not significantly different for children in group 1. However, verbal (88 +/- 13) and performance intelligence quotients (78 +/- 17) were significantly different for children in group 2. For children in group 2, their lowest scale scores were in object assembly, geometric design, mazes, and picture completion, all timed tests that involved visual discrimination of linear forms with small intersecting lines. In the 2 scales scored that did not differ between groups 1 and 2, arithmetic and block design, timing and vision but not linear forms were components of the tasks. Children with monocular and binocular normal visual acuity did not differ in verbal, performance, or full-scale intelligence quotients or any of the subscale tests. Difficulty with sight or concomitant neurologic involvement also seemed to impact the ability to acquire information, comprehension skills, and vocabulary and performance in similarities testing. After controlling for gender, however, these differences were diminished, and there were no longer differences in overall verbal scores. As noted above, results were generally similar when all of the tests for 3.5-year-olds or 5-year-olds were analyzed separately. At the 3.5-year visit there were fewer significant differences between the 2 groups for the verbal components than at the 5-year visit., Conclusions: In children with congenital toxoplasmosis and bilateral macular disease (group 2) because of toxoplasmic chorioretinitis, scaled scores were lowest on timed tests that require discrimination of fine intersecting lines. Although the severity of ocular and neurologic involvement is often congruent in children with congenital toxoplasmosis, ophthalmologic involvement seems to account for certain specific limitations on tests of cognitive function. Children with such visual impairment compensate with higher verbal skills, but their verbal scores are still less than those of children with normal vision, and in some cases significantly so, indicating that vision impairment might affect other aspects of cognitive testing. Patterns of difficulties noted in the subscales indicate that certain compensatory intervention strategies to facilitate learning and performance may be particularly helpful for children with these impairments. These patterns also provide a basis for the development of measures of cognitive function independent of visual impairment.

Inconsistent alertness and orientation (sluggishness, drowsiness, daydreaming) were reported to accompany Attention Deficit Disorder (ADD) without Hyperactivity in DSM-III. Such Sluggish Cognitive Tempo items were tested in the DSM-IV Field Trial for ADHD, but were discarded from the Inattention symptom list because of poor negative predictive power. Using 692 children referred to a pediatric subspecialty clinic for ADHD, Sluggish Tempo items were re-evaluated. When Hyperactivity-Impulsivity was absent (i.e., using only cases of Inattentive Type plus clinic controls), Sluggish Tempo items showed substantially improved utility as symptoms of Inattention. Factor analyses distinguished a Sluggish Tempo factor from an Inattention factor. When DSM-IV ADHD types were compared, Inattentive Type was uniquely elevated on Sluggish Tempo. These findings suggest that (a) Sluggish Tempo items are adequate symptoms for Inattentive Type, or (b) Sluggish Tempo may distinguish two subtypes of Inattentive Type. Either conclusion is incompatible with ADHD nosology in DSM-IV.