Risk-Taking Behavior in Juvenile Myoclonic Epilepsy

In the October 23, 2013, early view of the journal Epilepsia, Drs. Wandschneider and colleagues from the Department of Clinical and Experimental Epilepsy at the UCL Institute of Neurology in the United Kingdom assess risk taking behavior or impulsivity in patients diagnosed with juvenile myoclonic epilepsy.

In the study, 21 juvenile myoclonic epilepsy patients and 11 controls using a particular test known as the Iowa Gambling Task, which measures decision making, were evaluated. Performance on this test correlates with particular activation patterns during functional MRI working memory tasks.

The investigators found:

• A greater proportion of patients with seizures than seizure-free patients have difficulties in making appropriate or advantageous decision making, but there was no difference in performance between the seizure-free patients or the control subjects.
• Functional imaging of working memory showed that overall poor Iowa Gambling Task performance was associated with increased activation in the dorsolateral prefrontal cortex in juvenile myoclonic epilepsy patients.
• Impaired learning during the task and ongoing seizures were associated with bilateral medial prefrontal cortex and pre-supplementary motor area and right superior frontal gyrus and left dorsolateral prefrontal cortex activation.

Their study provides evidence that patients with juvenile myoclonic epilepsy and ongoing seizures learned significantly less from previous experience, and inter-ictal dysfunction within normal working memory networks, specifically within the dorsolateral prefrontal cortex and medial prefrontal cortex structures, affects their ability to learn.