Reduction of frontal neocortical grey matter associated with affective aggression in patients with temporal lobe epilepsy: an objective voxel by voxel analysis of automatically segmented MRI.
BACKGROUND
Interictal episodes of aggression are often reported in patients with epilepsy. Some have characteristics of what has been referred to as episodic dyscontrol or intermittent explosive disorder (IED). Although structural brain abnormalities are thought to play a part in the pathophysiology of aggression, there are few in vivo studies of structural cerebral changes in patients with epilepsy and aggression. Using quantitative MRI, subtle structural brain abnormalities can be investigated in subgroups of patients with both epilepsy and episodes of affective aggression.


METHODS
After automated segmentation of cerebral grey matter from T1 weighted MRI, the objective technique of statistical parametric mapping (SPM) was applied to the analysis of 35 control subjects, 24 patients with temporal lobe epilepsy (TLE) with a history of repeated, interictal episodes of aggression, and 24 patients with TLE without episodes of aggression. Both TLE patient groups were compared with each other and with the control subjects on a voxel by voxel basis for increases and decreases of grey matter.


RESULTS
The patients with TLE with aggressive episodes had a decrease of grey matter, most markedly in the left frontal lobe, compared with the control group and with patients with TLE without aggressive episodes.


CONCLUSIONS
These findings suggest that a reduction of frontal neocortical grey matter might underly the pathophysiology of aggression in TLE. These voxel by voxel comparisons can guide further in vivo studies into aggression.
Woermann
F G
FG
Epilepsy Research Group, Institute of Neurology, Department of Clinical Neurology and National Society for Epilepsy, Queen Square, London WC1N 3BG, UK.
van Elst
L T
LT
Koepp
M J
MJ
Free
S L
SL
Thompson
P J
PJ
Trimble
M R
MR
Duncan
J S
JS
D000293:Adolescent; D000328:Adult; D000374:Aggression; D002648:Child; D002675:Child, Preschool; D004569:Electroencephalography; D004833:Epilepsy, Temporal Lobe / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology*; D005260:Female; D005625:Frontal Lobe / Q000002:abnormalities* / Q000503:physiopathology; D006801:Humans; D007223:Infant; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D019964:Mood Disorders / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology*; D019579:Neocortex / Q000002:abnormalities* / Q000503:physiopathology; D011569:Psychiatric Status Rating Scales; D011594:Psychometrics / Q000706:statistics & numerical data