Behavioural expression of ictal embarrassment: a stereo-EEG case report

Embarrassment is a rare ictal manifestation whose neurophysiological basis remains poorly understood. We describe the case of a 40-year-old woman with drug-resistant focal epilepsy characterized by an unusual ictal semiology combining an intense positive emotional experience with behavioral manifestations of embarrassment. Stereo-EEG demonstrated seizure onset within the middle frontal gyrus bank of the superior frontal sulcus (F2sb), with rapid propagation to the dorsal anterior cingulate cortex (dACC) and superior anterior insula (sAI). Electrical stimulation of the F2sb reliably reproduced the habitual electroclinical seizure. While identical stimulation parameters elicited the subjective and autonomic manifestations in both supine and upright postures, the complete behavioral repertoire of embarrassment emerged only when stimulation was delivered in the standing position. Exploratory functional connectivity analyses revealed that overt embarrassment was associated with reduced node strength within a network encompassing the dACC, sAI, mesial prefrontal cortex (mPFC), and dorsolateral prefrontal cortex (dlPFC). More restricted network changes were associated with only mild sensations, whereas asymptomatic stimulation produced a distinct and partly reversed connectivity pattern. This case suggests that the behavioral expression of ictal embarrassment arises from the transient reconfiguration of a frontal-cingulo-insular network and is critically shaped by bodily context.