Amygdala subfield and prefrontal cortex abnormalities in patients with functional seizures

Nilab Nasrullah; Wesley T Kerr; John M Stern; Yanlu Wang; Hiroyuki Tatekawa; John K Lee; Amir H Karimi; Siddhika S Sreenivasan; Jerome Engel Jr; Dawn E Eliashiv; Jamie D Feusner; Noriko Salamon; Ivanka Savic

doi:10.1016/j.yebeh.2023.109278

Amygdala subfield and prefrontal cortex abnormalities in patients with functional seizures

Epilepsy Behav. 2023 Aug:145:109278. doi: 10.1016/j.yebeh.2023.109278. Epub 2023 Jun 23.

Authors

Affiliations

¹ Department of Women's and Children's Health, Karolinska Institute, Stockholm, Sweden; Neurology Clinic, Karolinska University Hospital, Stockholm, Sweden.
² Department of Neurology, Michigan Medicine, University of Michigan, Ann Arbor, MI, USA; Department of Neurology, David Geffen School of Medicine at the University of California Los Angeles, Los Angeles, CA, USA.
³ Department of Neurology, David Geffen School of Medicine at the University of California Los Angeles, Los Angeles, CA, USA.
⁴ Medical Radiation Physics and Nuclear Medicine, Karolinska University Hospital, Stockholm, Sweden.
⁵ Department of Radiology, David Geffen School of Medicine at the University of California Los Angeles, Los Angeles, CA, USA.
⁶ Department of Neurology, David Geffen School of Medicine at the University of California Los Angeles, Los Angeles, CA, USA; Department of Psychiatry and Biobehavioral Sciences, University of California Los Angeles, Los Angeles, CA, USA; Brain Research Institute, University of California Los Angeles, Los Angeles, CA, USA; Department of Neurobiology, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA.
⁷ Department of Women's and Children's Health, Karolinska Institute, Stockholm, Sweden; Department of Psychiatry and Biobehavioral Sciences, University of California Los Angeles, Los Angeles, CA, USA; Centre for Addiction and Mental Health, Toronto, Canada; Department of Psychiatry, University of Toronto, Toronto, Canada.
⁸ Department of Women's and Children's Health, Karolinska Institute, Stockholm, Sweden; Neurology Clinic, Karolinska University Hospital, Stockholm, Sweden; Department of Neurology, David Geffen School of Medicine at the University of California Los Angeles, Los Angeles, CA, USA. Electronic address: Ivanka.Savic-Berglund@ki.se.

PMID: 37356226
DOI: 10.1016/j.yebeh.2023.109278

Abstract

Background: Functional seizures (FS) are paroxysmal episodes, resembling epileptic seizures, but without underlying epileptic abnormality. The aetiology and neuroanatomic associations are incompletely understood. Recent brain imaging data indicate cerebral changes, however, without clarifying possible pathophysiology. In the present study, we specifically investigated the neuroanatomic changes in subregions of the amygdala and hippocampus in FS.

Methods: T1 MRI scans of 37 female patients with FS and 37 age-matched female seizure naïve controls (SNC) were analyzed retrospectively in FreeSurfer version 7.1. Seizure naïve controls included patients with depression and anxiety disorders. The analysis included whole-brain cortical thickness, subcortical volumes, and subfields of the amygdala and hippocampus. Group comparisons were carried out using multivariable linear models.

Results: The FS and SNC groups did not differ in the whole hippocampus and amygdala volumes. However, patients had a significant reduction of the right lateral amygdala volume (p = 0.00041), an increase of the right central amygdala, (p = 0.037), and thinning of the left superior frontal gyrus (p = 0.024). Additional findings in patients were increased volumes of the right medial amygdala (p = 0.031), left anterior amygdala (p = 0.017), and left dentate gyrus of the hippocampus (p = 0.035).

Conclusions: The observations from the amygdala and hippocampus segmentation affirm that there are neuroanatomic associations of FS. The pattern of these changes aligned with some of the cerebral changes described in chronic stress conditions and depression. The pattern of detected changes further study, and may, after validation, provide biomarkers for diagnosis and treatment.

Keywords: Amygdala; Chronic stress; Cortical thickness; Hippocampus; Psychogenic nonepileptic seizures.

Publication types

Research Support, Non-U.S. Gov't
Research Support, N.I.H., Extramural

MeSH terms

Amygdala* / diagnostic imaging
Epilepsy*
Female
Hippocampus / diagnostic imaging
Humans
Magnetic Resonance Imaging / methods
Prefrontal Cortex / diagnostic imaging
Retrospective Studies
Seizures / diagnostic imaging

Abstract

Publication types

MeSH terms

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