Executive Function Deficits and Emotion Recognition Problems In Boys with Klinefelter Syndrome, Related to Social Dysfunction and Autism

Background:

Klinefelter syndrome, determined by a XXY chromosomal pattern, affects approximately 1 in 700 male individuals and is the most common sex chromosomal disorder. Apart from a variety of phenotypes, like hypogonadism, androgen deficiency and infertility, cognitive and behavioral dysfunctions are recognized to be associated with this chromosomal pattern. Especially social dysfunction is reported. Shyness, high levels of social anxiety, social impulsiveness and social withdrawal have been found in Klinefelter man. High levels of autism traits in men with Klinefelter syndrome were reported by our group, findings that draw even more attention to the vulnerability for social dysfunctions associated with Klinefelter syndrome. Studies so far mainly focus on adult populations and data about the social development of boys with Klinefelter syndrome are scarce, although recent studies of our group revealed 25% autism related disorders in boys with Klinefelter. 

Objectives:

We addressed the question whether children with Klinefelter syndrome have EF problems and problems in social cognition that are associated with social problems and autism symptoms. The EF domains of attention regulation, inhibition and mental flexibility, were evaluated as well as the social cognition domains recognition of faces and the ability to recognize emotional expressions on faces.

Methods:

56 boys with Klinefelter syndrome (mean age 10.7) were compared to a group of 112 normal control boys, matched on age. Social dysfunction and autism symptoms were measured by the Child Behavior Checklist (CBCL) and the Autism Diagnostic Interview (ADI). Attention regulation was measured by a classic Continuous Performance Task (CPT), inhibition of processing of irrelevant information was indicated by the proportion of impulsive responses (misses) on the CPT. Mental (in)flexibility was indicated by the score on the incompatible respons on a set shifting task (SS-VIS) task. In addition, tasks of face recognition and facial emotion recognition were used as measures for social cognition.

Results:

35% of the Klinefelter population had scores above the clinical cut-off point on the social problem scale of the CBCL. 25% of the children did meet the criteria for autism on the ADI. Attention regulation was less well developed in Klinefelter boys ( p=.000). Klinefelter boys showed much difficulty in inhibition of responses ( p=.000) and their mental flexibility was less well developed (p=.000). Boys with Klinefelter were less accurate in recognition of faces (p=.001). They also had much more difficulty in fast and accurate recognition of emotional facial expression (p=.000).

Conclusions:

Boys with Klinefelter syndrome show difficulty with attention regulation, inhibition, and mental flexibility. These EF functions are known to be essential in regulation of thought and behavior, especially social adaptive behavior. Therefore, social adaptive problems in Klinefelter and autism symptoms, might be associated with less well developed EF. Moreover, children with Klinefelter syndrome appeared to have difficulty in recognition of faces and facial emotions, which is associated with social dysfunction as well.