Lynn K. Paul (Senior Research Scientist at California Institute of Technology, Director of the Corpus Callosum Research Program, Founding President of the National Organisation of Disorders of the Corpus Callosum, NODCC in 2002)

The research led by Dr Lynn Paul has focused on cognition and social skills in individuals with primary ACC. Dr Paul has worked closely with Prof Warren Brown on defining what they see as the core syndrome of ACC, how this manifests in everyday life and throughout the lifespan.

An important finding is the pattern of strengths and weaknesses often seen in individuals with primary ACC; skills that can be consolidated with practice and overlearning are achieved well, but difficulties arise with more complex, novel, or open-ended tasks. Dr Paul outlined the following as examples:

  • good basic reading skills, but relatively poor reading comprehension
  • good rote learning of simple calculations, but poor mathematical problem solving
  • strong basic language skills, but difficulties understanding the subtleties in language that occur in everyday conversation, such as non-literal expressions and humour

Not being able to appreciate second-level meanings in language can lead to many social vulnerabilities; Dr Paul has found high-functioning individuals with ACC may not reliably determine whether someone is being sincere or sarcastic, with an over-tendency towards thinking someone is being sincere. They also had some problems identifying emotions as conveyed by actors, with particular difficulty with negative emotions such as sadness, anger and fear. Interestingly, a recent study found individuals with ACC did not look at the eye region as much as typically developing controls when asked to judge how someone was feeling from a photograph, and this seemed to contribute to their difficulty in correctly identifying emotions.

Difficulties appreciating the intended meaning behind statements, coupled with misreading emotional information, leads to the suggestion that behaviours seen in individuals with ACC may overlap with those on the autism spectrum. Indeed, in a study of adults with ACC, 31% (8 from 26) presented with an autism spectrum disorder, with others being on the borderline range showing impairments in social interaction and communication.

Dr Paul observed that children with primary ACC who are generally functioning well during early childhood seem to “grow into their difficulties” with behavioural and social problems becoming apparent in later childhood and adolescence. It is thought that as the complexity of social information increases with age, as well as higher expectations, difficulties become more visible. However there are few studies that track early development and these problems may be apparent in younger children with ACC, but have not yet been systematically studied.

In response to this Dr Paul is conducting a longitudinal study of infants with ACC along with Prof Jed Elison (Institute of Child Development and Department of Pediatrics, University of Minnesota). This is the first study looking at the behavioural impact of disorders of the corpus callosum from birth into early childhood. Information is being collected from families through online questionnaires with the aim to better understand how ACC influences behaviour and neurological development during this critical period. Knowing these factors will help in the development of more effective intervention methods and support children and adults with ACC.

For more information about this study and how to enrol go to: http://emotion.caltech.edu/?page_id=11851