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Cortical and Subcortical Mechanisms of Time Perception
Dušek, Petr ; Jech, Robert (advisor) ; Mareš, Jaroslav (referee) ; Bareš, Martin (referee)
Deficits in interval timing have been described in focal brain lesions and in various neuropsychiatric disorders including Parkinson's disease (PD). The aim of this study was to explore brain areas responsible for human time perception and for the timing deficit in PD. We used a time reproduction task (TRT) which consisted of an encoding phase (during which visual stimuli of durations from 5 to 16.6 sec were presented) and a reproduction phase (during which interval durations were reproduced by a button pressing). In our first fMRI study, we used a parametric modulated analysis searching for brain areas with activity, expressed as Blood Oxygenation Level Dependent (BOLD) signal, correlated with the duration of time interval. During the encoding phase, there was a gradual deactivation of the left prefrontal cortex (PFC) and cingulate gyrus. During the reproduction phase, there was a gradual deactivation in precuneus and an accumulation of activity in the left PFC, primary motor area, right caudate and supplementary motor area (SMA). The second study aimed at supporting the role of two of these areas, SMA and precuneus in interval timing by repetitive transcranial magnetic stimulation (rTMS). Accuracy and variability of time estimates were compared before and after rTMS. Accuracy of estimates was not...
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Cortical and Subcortical Mechanisms of Time Perception
Dušek, Petr ; Jech, Robert (advisor) ; Mareš, Jaroslav (referee) ; Bareš, Martin (referee)
Deficits in interval timing have been described in focal brain lesions and in various neuropsychiatric disorders including Parkinson's disease (PD). The aim of this study was to explore brain areas responsible for human time perception and for the timing deficit in PD. We used a time reproduction task (TRT) which consisted of an encoding phase (during which visual stimuli of durations from 5 to 16.6 sec were presented) and a reproduction phase (during which interval durations were reproduced by a button pressing). In our first fMRI study, we used a parametric modulated analysis searching for brain areas with activity, expressed as Blood Oxygenation Level Dependent (BOLD) signal, correlated with the duration of time interval. During the encoding phase, there was a gradual deactivation of the left prefrontal cortex (PFC) and cingulate gyrus. During the reproduction phase, there was a gradual deactivation in precuneus and an accumulation of activity in the left PFC, primary motor area, right caudate and supplementary motor area (SMA). The second study aimed at supporting the role of two of these areas, SMA and precuneus in interval timing by repetitive transcranial magnetic stimulation (rTMS). Accuracy and variability of time estimates were compared before and after rTMS. Accuracy of estimates was not...
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