Neural correlates of deficient response inhibition in mentally disordered violent individuals.
In this study, response inhibition and associated neural activation during a motor inhibition paradigm were investigated in (i) men with antisocial personality disorder (APD) with a history of violence (n = 14), (ii) men with schizophrenia with a history of violence (n = 12), (iii) men with schizophrenia without a history of violence (n = 12), and (iv) healthy control subjects (n = 14) using functional magnetic resonance imaging (fMRI). At the behavioural level, individuals with schizophrenia showed impaired performance across all conditions, whereas an increased error rate was seen in the APD group only during the conditions requiring inhibition. At the neural level, both violent groups showed reduced thalamic activity, compared with controls, in association with modulation of inhibition by task demands. In addition, the violent schizophrenia group, compared with controls, showed reduced activity in the caudate nucleus during the condition requiring inhibition. It is concluded that violence may not be specifically associated with impaired voluntary inhibition in schizophrenia but this is likely in APD. Reduced thalamic function, perhaps due to its known association with sensorimotor disturbances, is implicated in violent behaviour across both disorders. In addition, caudate dysfunction may contribute, given its role in timing and temporal processing as well as suppression of motor actions, to deficient inhibition and violent behaviour in schizophrenia.
Barkataki
Ian
I
Department of Psychology, School of HumanSciences, University of Surrey, Guildford GU2 7HX, UK. ibarkataki@gmail.com
Kumari
Veena
V
Das
Mrigen
M
Sumich
Alex
A
Taylor
Pamela
P
Sharma
Tonmoy
T
D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D000987:Antisocial Personality Disorder / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000523:psychology*; D016022:Case-Control Studies; D002421:Caudate Nucleus / Q000503:physiopathology; D006801:Humans; D007266:Inhibition, Psychological; D008279:Magnetic Resonance Imaging; D008297:Male; D001523:Mental Disorders; D008875:Middle Aged; D009474:Neurons; D011569:Psychiatric Status Rating Scales; D011859:Radiography; D012559:Schizophrenia / Q000000981:diagnostic imaging / Q000503:physiopathology; D012565:Schizophrenic Psychology; D014584:User-Computer Interface; D014754:Violence / Q000523:psychology*