BACKGROUND Research suggests an association between frontal and temporal injury and antisocial conduct. We studied the frequency of antisocial behaviours in fronto-temporal dementia (FTD) where pathology is anterior frontal-temporal, compared with Alzheimer's disease (AD) where pathology is primarily posterior temporal-parietal.
METHOD The presence of antisocial conduct was compared in 22 FTD versus 22 AD subjects. All FTD patients had anterior frontal or temporal hypoperfusion with single photon emission computed tomography, whereas those with AD had posterior temporal-parietal hypoperfusion.
RESULTS Ten FTD and one AD subject showed antisocial behaviours, which included assault, indecent exposure, shoplifting and hit-and-run driving. Three FTD subjects were arrested. This difference was highly significant (P = 0.004).
CONCLUSIONS Degeneration of frontal and temporal lobes predisposes to antisocial behaviour. This study supports a relationship between frontal-temporal dysfunction and certain types of antisocial activities.