Comprehension of Proverbs in Individuals With Agenesis of the Corpus Callosum
Individuals with agenesis of the corpus callosum (ACC) can have normal measured intelligence and still show deficits in non-literal language comprehension. The nature of these deficits, however, is not entirely clear. Two experiments were run to analyze the relationship between ACC and proverb comprehension. In Experiment 1, 16 adults with complete or partial ACC and a full-scale intelligence quotient (FSIQ) equal to or greater than 80 (FSIQ ≥ 80) were compared to 13 control participants (FSIQ ≥ 80) in performance on the Gorham’s proverbs task (1956). In Experiment 2, 14 adults with complete or partial ACC (FSIQ > 80) were compared to 15 control participants (FSIQ ≥ 80) in performance on the proverbs subtest of the Delis-Kaplan Executive Function System (DKEFS, 2001). Additionally, Education, the Verbal Comprehension Index (VCI) and Performance Intelligence Quotient (PIQ) or Perceptual Organization Index (POI) of the Wechsler Adult Intelligence Scale, Third Edition (WAIS-III), as well as the non-literal and literal items of the Familiar and Novel Language Comprehension task (FANL-C) were used as covariates based on previous research that had showed evidence of shared variance between these or similar scales and proverb comprehension. The results showed a significant effect for groups on the free response task in both experiments, after controlling for VCI, such that the ACC groups were not able to generate interpretations for proverbs that were as accurate as those of the control groups. No group differences were found on the multiple-choice format in either experiment, and this did not change after introducing covariates.
Doctor of Philosophy in Clinical Psychology (PhD)
Brown, Warren S.
Corpus callosum, Abnormalities, Agenesis of corpus callosum