Neuroanatomic correlates of psychogenic nonepileptic seizures: A cortical thickness and VBM study

Abstract

SUMMARYPurpose: Psychogenic nonepileptic seizures (PNES) are among the most common clinical manifestations of conversion disorder and consist of paroxysmal behavior that resembles epileptic seizures. Preliminary data from functional neuroimaging studies gave plausible evidence that limbic circuits and sensorimotor cortex might be engaged in conversion disorder. Nonetheless, no advanced magnetic resonance imaging (MRI) studies have focused on patients with PNES. Methods: We enrolled 20 consecutive patients in whom the diagnosis of PNES was based on ictal video-electroencephalography (EEG) of the habitual episodes and 40 healthy subjects matched for age and sex All patients underwent a formal neuropsychological investigation and a neuropsychiatric assessment. All of the patients also underwent two distinct morphologic whole-brain MR measurements, voxel-based morphometry (VBM), and cortical thickness analysis, in a multimethod approach.Key Findings: None of the patients had serious medical or neurologic illness, substance abuse, or psychotic disorder, or were taking antipsychotic drugs. VBM and cortical thickness analyses in the patients with PNES revealed abnormal cortical atrophy of the motor and premotor regions in the right hemisphere and the cerebellum bilaterally. We also observed a significant association between increasing depression scores and atrophy involving the premotor regions. Significance: The results of this study illustrate that motor and premotor regions in the right hemisphere and the cerebellum bilaterally play an important role in the pathogenesis of PNES and that these structures are correlated with depressive symptoms. Our findings suggest a multistep model in the pathogenesis of PNES, in which the phenomenology is driven by psychological factors interacting with specific biologic abnormalities.

Neural generators of psychogenic seizures: Evidence from intracranial and extracranial brain recordings

“…Van der Kruijs and colleagues found stronger connectivity values between regions involved in emotion (insula), executive control (inferior-frontal and parietal cortices), and movement (precentral sulcus) [6]. Using voxel-based morphometry, Labate and colleagues [7] found abnormal cortical atrophy of the motor and premotor regions in the right hemisphere and the cerebellum bilaterally. Using EEG, Krishnan et al found "resetting" of brain dynamics in patients with ESs but not in patients with PSs [8].…”

Excitatory and inhibitory conversive experiences: neurobiological features involving positive and negative conversion symptoms

“…A decrease in the right motor and premotor cortex as well as in the cerebellum thickness has been found in patients with pseudoepileptic seizures (Labate et al, 2012). Van der Kruijs described a greater connectivity between emotion-related areas (insula), executive control areas (inferior frontal gyrus and parietal cortex) and movement control regions (precentral sulcus) in these patients.…”

Pszichogén nem epilepsziás rosszullétek a klinikai gyakorlatban

“…Labate és mtsai a corticalis vastagságot -köztük a szür-keállomány-térfogatot -vizsgálták voxelalapú morfometriával, amely az egészséges kontrollcsoporthoz viszonyítva a PNER-betegek körében szignifikáns corticalis elvékonyodást jelzett a jobb agyfélteke primer motoros és premotoros, valamint a kisagy bilateralis területein [50]. Az eredmények azonban fenntartásokkal kezelen-dők, mivel szinte az összes vizsgálati személyt depresszióval is diagnosztizálták; hasonló strukturális eltéréseket pedig depresszióban is kimutattak [51].…”