Conversely, manic patients have the feeling of time passing more quickly than it actually is.49,50 In the duration production tasks, depressive patients are particularly impaired for the longer durations. This result is explained by the requirement of supplementary cognitive processes, in particular attention and memory, in time estimation in the second-to-minute range.47 Time estimation impairments in depressive patients have also been associated with retardation. Indeed, depressive patients
are known to show impaired executive functions as well as a slowing processing speed.51,52 The assessment of productions of long durations (35 and 90 s) reveal that both depressed and manic patients overestimate Inhibitors,research,lifescience,medical time, with the manic group Inhibitors,research,lifescience,medical overestimating even more prominently.48 The overestimation of time in manic patients (ie, shorter durations produced) appear compatible with the accelerated rate of mental events and agitation in these patients. Overestimation of time in depression is more difficult to explain. Although both groups
of depressed and manic patients show greater retardation compared with controls, there were no significant correlations between retardation and time productions in none Inhibitors,research,lifescience,medical of both groups. Thus, impaired productions in patients with affective disorders could be due to memory deficits. In the reproduction of durations in the second range (1 s, 6 s, and 37 s), which is supposed to involve memory, manic patients underestimate Inhibitors,research,lifescience,medical the long duration and depressive patients overestimate the short duration.49 A recent study has shown a similar pattern of impaired reproductions in depressed and manic patients related to severity of illness.50 Additional measurement of short-term and ABT-888 datasheet longterm memory
would be necessary to better understand the relationships between time estimation Inhibitors,research,lifescience,medical and memory in patients with affective disorders. A time estimation deficit in patients with schizophrenia is also often reported.53-55,57 Also, schizophrenic patients exhibit attention and memory dysfunctions as well as metabolic alterations, including in the dopaminergic systems.56 The results show a tendency for patients with schizophrenia to overestimate time and to be less accurate in time estimation tasks than controls.53 Results have been interpreted as a deficit in a specific timing process. However, most of these studies used other time estimation paradigms than the production Calpain and reproduction tasks, as well as short time intervals.54,57 Some authors investigated time productions in patients with schizophrenia and manipulated the amount of attention allocated to time.55 The results showed that the negative effect of the dual task paradigm on the accuracy of time productions was higher for the schizophrenic patients than for the controls. Thus, the authors explained the altered temporal judgments in schizophrenia by working memory deficits.