Dissociation in epilepsy and conversion nonepileptic seizures

Area of Science:

• Neuroscience
• Psychiatry
• Psychology

Background:

• The Dissociative Experiences Scale (DES) is widely used to assess dissociative symptoms.
• Understanding the dimensionality of the DES is crucial for accurate interpretation in clinical populations.

Purpose of the Study:

• To examine the item content dimensionality of the Dissociative Experiences Scale (DES).
• To investigate the relationship between DES dimensions and clinical diagnoses of conversion nonepileptic seizures (C-NES) versus complex partial epilepsy (CPE).

Main Methods:

• A sample of 132 patients with C-NES and 169 with complex partial epilepsy (CPE) completed the DES.
• Factor analysis using principal components analysis (PCA) with varimax rotation was performed on the DES data.

Main Results:

• Principal components analysis revealed distinct factors within the DES, differentiating C-NES and CPE groups more effectively than total scores.
• A 'depersonalization-derealization' factor was significantly higher in the C-NES group.
• An 'absorption-imaginative involvement' factor was associated with childhood abuse history, irrespective of diagnosis.
• An 'amnestic' factor showed a trend toward elevation in CPE, potentially confounding distinctions based on total DES scores.

Conclusions:

• The DES comprises separate dimensions related to depersonalization/derealization, childhood trauma, and neurological impairment.
• The heterogeneous nature of DES items can act as a confound when studying dissociation in neuropsychiatric populations, requiring careful consideration.