Adaptive behavior in primary agenesis of the corpus callosum

Background and aims: Primary agenesis of the corpus callosum (ACC) is a congenital neurological disorder characterized by the absence, either partial or complete, of the corpus callosum in individuals who do not have intellectual disability and are otherwise neurologically asymptomatic. While mild to moderate neurocognitive deficits have been observed in individuals with primary ACC using neuropsychological assessments, the impact of this syndrome on adaptive behavior remains insufficiently understood.

Methods: This study used self- and informant-ratings on the Adaptive Behavior Assessment System, Second Edition (ABAS-II) to evaluate adaptive behavior in 35 adults diagnosed with primary ACC.

Results: While adults with primary ACC reported adaptive functioning comparable to an age-adjusted normative sample, family informants rated their adaptive ability below norms in several skill domains, particularly social skills.

Conclusions: This pattern of lower ratings by informants than self-ratings suggests adults with ACC may have poor understanding of their own behavior and its consequences. This study demonstrates that informants observe significant deficiencies in the conceptual, social, and practical aspects of adaptive behavior in persons with primary ACC, and that these deficiencies are not seen as clearly by the persons themselves.