Cognitive and psychosocial deficits in agenesis of the corpus callosum with normal intelligence

Abstract

Introduction. Cognitive disabilities in agenesis of the corpus callosum (ACC) have been described in scattered reports, but few complete case descriptions are available. Consequent psychosocial disabilities in ACC have received little attention. We expected that ACC would be manifest in deficits specific to complex reasoning, concept formation, and problem solving. We also expected that these cognitive problems would be particularly evident in difficulties interpreting and understanding social situations, and in abnormal self-perception. Methods. Cognitive and psychosocial deficits were studied in two adolescents with ACC and normal IQ using a battery of cognitive and psychological tests. Results. Test results indicated poor interhemispheric integration of complex material. Performance on tests of reasoning, and concept formation were clearly below expectations based on IQ. Significantly poor performance was also found on tests of social insight, proverb interpretation, social logic, self-perception, and interpretation of ambiguous stimuli. Gross behavioural disorder or psychopathology were not found. Conclusions. ACC results in disabilities in social cognition that appear to be secondary to deficits in complex cognitive operations such as reasoning, concept formation, and problem solving. It is suggested that these cognitive deficits may be related to diminished interhemispheric transfer of complex information.

Social and Behavioral Problems of Children with Agenesis of the Corpus Callosum

“…As of yet, the pattern of consistent cognitive deficits in ACC has not been fully described. However, our results thus far, and those appearing in the research literature, suggest that high-functioning adults with ACC typically have moderate but detectable deficits in the following areas: interhemispheric transfer of complex sensory information and learning [15][16][17][18][19][20]; bimanual motor coordination [18,21,22]; complex novel problem-solving [13,14,[23][24][25][26]; processing of subtle phonetic and semantic aspects of language [13,[27][28][29][30][31][32]; comprehension of second-order meanings of language [33][34][35]; and psychosocial understanding and behavior [14,35]. Since the individuals with ACC that we have studied have complete ACC, normal IQs, and few, if any, other structural brain abnormalities, we refer to this form of ACC as Primary ACC.…”

“…Recent research is consistent in suggesting that these seemingly ''asymptomatic'' individuals with ACC nevertheless have areas of specific cognitive deficit or learning disability [13,14]. As of yet, the pattern of consistent cognitive deficits in ACC has not been fully described.…”

“…Both anecdotal evidence and accumulating research suggest that high-functioning children with autism and children with Primary ACC have in common certain forms of social disability [14,39]. In addition, high-functioning individuals with autism and ACC also share diminished ability to infer what other people are thinking, referred to as ''theory of mind'' [40,41] and deficits in abstract reasoning [14,[42][43][44][45].…”

Regional atrophy of the corpus callosum in dementia

“…Studies of on neuropsychological and psychosocial outcomes in high-functioning (FSIQ . 80) individuals with ACC by Brown and colleagues (e.g., Brown & Paul, 2000) have suggested a syndrome of cognitive deficiencies in the following areas that are associated with callosal absence (described in detail in Badaruddin et al, 2007): interhemispheric transfer of complex sensory information and learning; bimanual motor coordination; complex novel problem-solving; comprehension of second-order meanings of language; speed of cognitive processing; and psychosocial understanding and behavior. Whereas there are many differences between ACC and dementing illnesses, it is not unreasonable to expect that degeneration of the CC in dementia would contribute to the outcome in these same cognitive domains.…”

A Neuropsychological Profile for Agenesis of the Corpus Callosum? Cognitive, Academic, Executive, Social, and Behavioral Functioning in School-Age Children

“…In contrast, executive functions, reading and spelling skills were relatively preserved. Studies examining social functioning in individuals with AgCC report a range of impairments, such as reduced understanding of jokes and humor (Brown, Paul, Symington, & Dietrich, 2005), proverb and non-literal items (Paul, Van Lancker-Sidtis, Schieffer, Dietrich, & Brown, 2003), complex social scenes (Brown & Paul, 2000;Paul, Schieffer, & Brown, 2004;Turk, Brown, Symington, & Paul, 2010), integration of social information from multiple sources (e.g., paralinguistic cues, nonliteral language; Symington, Paul, Symington, Ono, & Brown, 2010), story-generation skills (Paul et al, 2004), and difficulties experiencing and thinking about complex but not basic emotions in the context of social interactions (L. B. Anderson, Paul, & Brown, 2017).…”