BACKGROUND/AIM: Working memory (WM) and attentional deficits have been implicated in the pathophysiology of both obsessive-compulsive disorder (OCD) and opioid addiction. The P300 component of event-related potentials (ERPs) is considered as an index of on-line updating of WM and/or attentional operations involved in this function. The present study aimed at comparing the P300 elicited during a WM test in patients with prolonged heroin abstinence, those with OCD and healthy controls, in order to demonstrate possibly common underlying psychophysiological mechanisms. METHODS: The P300 component was evaluated during the anticipatory period of a WM test in 20 patients characterized by a past history of opioid dependence (6 months abstinence), in 18 OCD patients, and 20 healthy subjects matched for age, sex and educational level. RESULTS: The two patient groups showed a considerable reduction of the P300 amplitudes, located at the right frontal area as compared with healthy controls. The abstinent heroin addicts exhibited a significantly lower P300 amplitude at central frontal areas and a significantly higher P300 amplitude at the left occipital region relative to the other two groups. Furthermore, the abstinent group showed a notable delay of P300 latency relative to controls and OCD patients at the right occipital region. Moreover, the OCD patients manifested a significant prolongation of P300 located at the central prefrontal area, relative to addicts and healthy controls. CONCLUSIONS: These findings point to considerable WM and/or attentional deficits in the long-term abstinent syndrome of heroin misuse and OCD associated with distributed and prefrontal cortical circuits, respectively. Furthermore, the present findings suggest that both OCD and long-term abstinent heroin addicts may share a common impairment of WM and/or attention involving or affecting the right prefrontal areas. Copyright 2003 S. Karger AG, Basel
BACKGROUND/AIM: Working memory (WM) and attentional deficits have been implicated in the pathophysiology of both obsessive-compulsive disorder (OCD) and opioid addiction. The P300 component of event-related potentials (ERPs) is considered as an index of on-line updating of WM and/or attentional operations involved in this function. The present study aimed at comparing the P300 elicited during a WM test in patients with prolonged heroin abstinence, those with OCD and healthy controls, in order to demonstrate possibly common underlying psychophysiological mechanisms. METHODS: The P300 component was evaluated during the anticipatory period of a WM test in 20 patients characterized by a past history of opioid dependence (6 months abstinence), in 18 OCDpatients, and 20 healthy subjects matched for age, sex and educational level. RESULTS: The two patient groups showed a considerable reduction of the P300 amplitudes, located at the right frontal area as compared with healthy controls. The abstinent heroin addicts exhibited a significantly lower P300 amplitude at central frontal areas and a significantly higher P300 amplitude at the left occipital region relative to the other two groups. Furthermore, the abstinent group showed a notable delay of P300 latency relative to controls and OCDpatients at the right occipital region. Moreover, the OCDpatients manifested a significant prolongation of P300 located at the central prefrontal area, relative to addicts and healthy controls. CONCLUSIONS: These findings point to considerable WM and/or attentional deficits in the long-term abstinent syndrome of heroin misuse and OCD associated with distributed and prefrontal cortical circuits, respectively. Furthermore, the present findings suggest that both OCD and long-term abstinent heroin addicts may share a common impairment of WM and/or attention involving or affecting the right prefrontal areas. Copyright 2003 S. Karger AG, Basel
Authors: Muhammad A Parvaz; Nelly Alia-Klein; Patricia A Woicik; Nora D Volkow; Rita Z Goldstein Journal: Rev Neurosci Date: 2011-11-25 Impact factor: 4.353