Acute alteration of emotional behaviour in epileptic seizures is related to transient desynchrony in emotion-regulation networks.
OBJECTIVE
During focal epileptic seizures, patients may express intense agitation, screaming and facial expressions of rage, fear or anger. The precise anatomical origin of such intense ictal emotional behaviour is not fully understood and the mechanisms by which the epileptic discharges provoke these phenomena are unknown. In the present study, we analysed the neurophysiological mechanisms underlying ictal emotional behaviour in 3 patients with frontal lobe epilepsies undergoing intracerebral recordings for presurgical evaluation.


METHODS
We analyzed the interactions between regions forming 'emotional networks', before and during behavioural alterations. Intracerebral recordings (SEEG method) of seizures from 3 patients presenting with frontal lobe seizures were analyzed. A nonlinear measure of SEEG signal interdependencies was used to evaluate the functional couplings occurring between brain structures.


RESULTS
We found that these intense emotional alterations were associated with a decrease of synchrony between signals recorded from the neural networks known to be involved in emotional processing, and in particular a loss of synchrony between the orbito-frontal cortex and the amygdala. This disruption of functional connections could then result in the disruption of emotional regulation leading to the release of altered behaviour, as observed in epileptic patients during seizures.


CONCLUSIONS
We propose that the occurrence of intense ictal emotional behaviour disturbance in frontal lobe seizures is related to a disruption of the normal mechanisms of emotional regulation


CONCLUSIONS
These results provide some insight into our understanding of the pathophysiological processes involved in human partial epilepsies as well as in the interpretation of clinical semiology.
Bartolomei
Fabrice
F
Service de Neurophysiologie Clinique, INSERM EMI 9926, CHU TIMONE et Université de la Méditerranée, 264 Rue Saint-Pierre, 13385 Marseille Cedex 5, France. fabrice.bartolomei@ap-hm.fr
Trébuchon
Agnes
A
Gavaret
Martine
M
Régis
Jean
J
Wendling
Fabrice
F
Chauvel
Patrick
P
D000328:Adult; D001519:Behavior / Q000502:physiology*; D003344:Cortical Synchronization; D003627:Data Interpretation, Statistical; D004567:Electrodes, Implanted; D004569:Electroencephalography; D004644:Emotions / Q000502:physiology*; D004827:Epilepsy / Q000503:physiopathology / Q000523:psychology*; D005260:Female; D005625:Frontal Lobe / Q000503:physiopathology; D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009415:Nerve Net / Q000503:physiopathology*; D012640:Seizures / Q000503:physiopathology / Q000523:psychology; D012815:Signal Processing, Computer-Assisted; D013702:Temporal Lobe / Q000503:physiopathology