Cognitive Impairment Is Not Equal in Patients with Epileptic and Psychogenic Nonepileptic Seizures

Abstract

Summary:Purpose: Patients with psychogenic nonepileptic seizures (PNES) and those with epileptic seizures (ES) purportedly have roughly equal neurocognitive deficits. However, recent findings suggest that patients with somatoform disorders exhibit more variable effort on neurocognitive testing than do controls. We reexamined neurocognitive function in patients with ESs and PNES by using symptom validity testing to control for variability in effort.Methods: Patients referred for video-EEG monitoring were administered the Word Memory Test (WMT), a measure of symptom validity, as part of neuropsychological evaluation. Patients classified with ictal video-EEG recordings as having ES (n = 41) or PNES (n = 43) were compared on neurocognitive and WMT performance and demographic, psychiatric, and medical variables.Results: Striking rates of WMT failure were observed in the PNES (51.2%) group, but not in the ES (8.1%) group (p = <0.001) after controlling for false-positive errors. Although the PNES and ES groups reported equivalent neurologic histories, the PNES group exhibited less objective evidence of impairment as measured by valid neuropsychological testing, MRI of the brain, and video-EEG monitoring.Conclusions: Many patients with PNES do not put forth maximal effort during neuropsychological assessment. When patients with PNES put forth valid effort, they demonstrate less objective evidence of neuropathologic injury or disease than do patients with ES. The cognitive impairment reported by this group appears to be more a function of motivational (although not necessarily intentional) factors than of verifiable neuropathology.

Explicit Facial Emotion Processing in Patients With Dissociative Seizures

“…There has been some literature suggesting that poor performance on cognitive tests in this group might be explained by reduced effort (61). However, this explanation does not adequately explain the specificity of the deficits to recognition accuracy, as it might be expected that reduced effort would also lead to poor performance for intensity judgements and/or on the standardised cognitive tests administered here.…”

Functional Neuroanatomy and Neurophysiology of Functional Neurological Disorders (Conversion Disorder)

“…122 Binder et al 123 compared individuals with intractable seizures, showing that patients with PNES (N=34) had fewer correct on the Portland Digit Recognition Test (PDRT). Drane et al 124 compared individuals with PNES (N=43) and ES (N=70) using the WMT and a battery of cognitive tests, which provided the Dodrill Discrimination Index (DDI) or percentage of scores falling in the abnormal range. Although both groups had the same DDI score (50.3 versus 52.6), patients with PNES who failed the WMT performed much worse on the DDI than those who did not fail the WMT.…”

Functional (Psychogenic) Cognitive Disorders: A Perspective from the Neurology Clinic

“…A Dutch study of nearly 2000 healthy subjects found that as many as 29% of people aged [25][26][27][28][29][30][31][32][33][34][35] considered themselves forgetful, rising to 34% (40-50 years), 41% (55-65) years and 52% between 70-85 years [3]. High proportions (47-60%) of these respondents said they were worried to some extent about their forgetfulness Complaints of forgetfulness were correlated with depression and poor subjective health.…”