Distinct Response Inhibition Patterns in Obsessive Compulsive Disorder Patients and Pathological Gamblers.

Background: Obsessive-compulsive disorder (OCD) and pathological gambling (PG) are common disorders. The cognitive models of OCD and PG focus on abnormalities in response inhibition. Although, these functions have been studied in different PG and OCD samples, no study has compared the response inhibition in both. Methods: Medication-naïve OCD (n = 61) and PG subjects (n = 109) and healthy controls (n = 131) performed CPT and Go/NoGo tasks. Results: Compared to healthy controls (HC), PG and OCD groups underperformed on speed and exhibited larger time variability on the CPT and Go/NoGo task. Only in OCD patients, a positive correlation between omission errors and response time (RT) was observed in the CPT. At the Go/NoGo task, a negative correlation between false alarms and RT (a fast-errors trade-off) was significant only in the PG group. The HC group had greater sensitivity values (d') than the OCD and PG groups in the Go/NoGo task. The PG group displayed lower d' values and more conservative response criterion in the CPT. In addition, only the OCD group expressed a high switching cost compared to both the PG and HC groups in terms of the RT and d' values. Conclusions: Both the PG and OCD groups demonstrated impaired response inhibition compared to the HC group. On several measures, the OCD and PG groups showed comparable impairments, and in others these were distinct. Thus, it appears that distinct neurocognitive patterns are involved in performance of the CPT and the Go/NoGo tasks among OCD and PG subjects whose cognitive status is currently under intensive investigation.

Hamilton Depression Scale in dementia.

INTRODUCTION: Wide variations in frequency of depression in primary degenerative dementia (PDD) and in vascular dementia (VD) have been reported. This may perhaps be due to inadequacy of common diagnostic tools in detecting depression in the face of cognitive decline. We evaluated here the Hamilton Depression Rating Scale (HDRS) in demented patients with PDD and VD. METHODS: We examined 50 consecutive patients with PDD and 50 consecutive patients with VD. All patients underwent neurological examination and their depression was evaluated using DSM-III-R criteria and the HDRS. The data obtained were analysed for distribution of depression and pattern of responses obtained in the HDRS. Sensitivity, specificity and Youden's J-indices for different cut-off scores of the HDRS in its ability to detect depression in this population were calculated. RESULTS: Dementia was associated with depression in 38% of the patients (DSM-III-R criteria). HDRS scores were higher in depressed patients (z= -5.7, P < 0.0001) with an HDRS cut-off score of 10 being indicative of depression in demented patients. Symptoms related to 'affective' components of the HDRS (such as depressive mood and anxiety) were strongly associated with the diagnosis of depression (Mann-Whitney tests, P < 0.0001). CONCLUSION: Depression is frequent in demented patients. The HDRS has good criterion validity in the evaluation of depression in demented patients. (Int J Psych Clin Pract 2002; 6: 91-94).