PNES, Intelligence and Mental Functions

Psychogenic Non Epileptic Seizures Information

What are intelligence and mental functions like in persons with PNES?

• Intellectual functioning of patients with PNES ranges from the very superior range to the intellectually disabled range. However, most often IQ scores lie in the normal range.

• Patients with PNES report considerable difficulties with memory, attention and concentration, and word finding and other language functions. It is for this reason that neuropsychological testing is often conducted to determine whether this is a quantifiable problem that requires remediation.

For example, a recent study our group conducted compared executive functions (planning and organizing, problem solving, attention, working memory, mental flexibility, set shifting) in patients with psychogenic non-epileptic seizures (PNES) and temporal lobe epilepsy patients (TLE). In order to make sure that everyone who was included made a good effort we removed those who did not pass a test that looks at symptom exaggeration from our analysis.
Deficits in working memory and executive functioning have already been reported in patients with psychogenic seizures (Chapman et al., 2011). We looked at whether those with a diagnosis of PNES had problems in executive functioning that were similar to those with temporal lobe epilepsy. We thought they might but needed to verify it and in order to do it, we gave both groups of patients a battery of tests that assessed different types of executive functioning. We had 97 patients with psychogenic non epileptic seizures and 89 patients with temporal lobe epilepsy.
We found that a similarly large number of patients with psychogenic non-epileptic seizures and temporal lobe epilepsy had weaknesses on tests of executive function. Eighteen to 23 percent of patients with psychogenic seizures and 22 to 30% of patients with temporal lobe epilepsy earned below normal scores on all three executive function subtests. These findings are intriguing and support that future studies to continue to explore these issues and new studies to check that this finding comes up again are needed. Future research should also explore what might be contributing to these problems in both of these patient groups.

A recent publication of ours from 2014 (Cognitive differences between patients who have psychogenic nonepileptic seizures (PNESs) and posttraumatic stress disorder (PTSD) and patients who have PNESs without PTSD) revealed that patients with PNESs who also had PTSD performed significantly worse on episodic verbal memory (narrative memory); had greater self-reported Total, Verbal, and Visual Memory impairments; and had higher substance abuse history and use of psychopharmacological agents compared with patients without PTSD regardless of a history of trauma. These findings are proving helpful in identifying discrete intragroup differences within PNESs.