” Consequently, these studies underline that the brain structures and cognitive processes involved in time estimation may differ according to the paradigm used. In the last few years, a number of neuropsychological studies have been aimed at clarifying the relationships between time estimation and cognition by investigating time judgments in patients who present memory and attention dysfunctions following brain damage. In this Inhibitors,research,lifescience,medical article, we report on time estimation in
the second range. Time estimation: neuropsychological studies We conducted a series of neuropsychological studies using the same paradigm in an amnesic patient,30 in epileptic patients with temporal lobe resections,31 in traumatic brain selleck compound injury (TBI) patients,32 and in patients with Parkinson’s disease.33 Two time estimation tasks were used (duration reproduction task and production task), in two conditions (control counting and concurrent reading conditions), Inhibitors,research,lifescience,medical with the same three target durations (5, 14, and 38 seconds). Inhibitors,research,lifescience,medical In the control counting condition, the participants were told to count aloud for the stimulus duration, as regularly as possible and at the rate they preferred, throughout the encoding and the reproduction phases of the reproduction task and the production task. In the concurrent
reading condition, subjects were told to read aloud digits throughout the encoding phase of the reproduction task and until they felt that the target duration was over in the production task. Results will be described and discussed in the frame of other neuropsychological studies using a similar
paradigm. Inhibitors,research,lifescience,medical Time estimation in an amnesic patient The well-known patient “HM” was the first amnesic patient who was investigated regarding his duration judgments,34 and studies with other amnesic patients, Inhibitors,research,lifescience,medical or those with Korsakoff’s syndrome, have led to the same findings.35-37 Our patient, “AC,” was profoundly amnesic with an impairment of episodic memory, while semantic memory was relatively Florfenicol spared.38 The performances of AC on the reproduction and production tasks revealed a clear dissociation. In the reproduction task, AC exhibited a consistent underestimation of the longer durations (14 s and 38 s), while he performed similarly to control subjects in the production for the same durations. Considering the selectivity of AG’s memory deficit due to his medial temporal lesions, the underestimations in the reproduction task could come from a failure in the retrieval of information from episodic memory. Encoding temporal information (ie, time basis pulses) for the long durations would exceed the short-term memory capacity of AC.