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Research findings link rolandic beta-band activity to voluntary movements, but a linkage with the decision time to move remains unknown. We found that beta-band (16-28Hz) activity shortly before the movement onset is relevant for the decision time to move: the more pronounced the decrease in beta-band synchronization, the earlier the subjective experience of the decision to move. The linkage was relevant regarding 'decision', but not regarding 'intention' timing that has been often applied in the study of free will. Our findings suggest that oscillatory neural activity in the beta-band is an important neural signature pertaining to the subjective experience of making a decision to move.
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The "dual klepsydra model" (DKM) of internal time representation successfully models duration reproduction data, but relations between the DKM-based parameter kappa ("loss rate") and procedural variables (presentation modality) or individual characteristics (cognitive indices, age, sex) remained as yet unexplored. For that purpose, were-analyzed data from an earlier time reproduction study (N = 100), using visually or acoustically presented intervals of 1-5 sec. duration. Typical values of parameter kappa were approximately 0.03-0.04 sec.(-1), corresponding to relaxation times of internal "lossy integrators" of approximately 30 sec. Significant effects of presentation modality (smaller kappa values for the visual reproduction task) and of age (greater kappa in acoustic reproduction with increasing age) were observed. Cognitive variables (working memory, general fluid reasoning, attention) and sex of participants were not associated with kappa. Cognitive functions seem to play only a minor, if any, role at the level of time representation addressed by the DKM.
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The present paper investigates the effects of age, sex, and cognitive factors on temporal-order perception. Nine temporal-order tasks were employed using two and four stimuli presented in the auditory and visual modalities. Significantly increased temporal-order thresholds (TOT) in the elderly were found for almost all tasks, while sex differences were only observed for two tasks. Multiple regression analyses show that the performance on most temporal-order tasks can be predicted by cognitive factors, such as speed of fluid reasoning, short-term memory, and attention. However, age was a significant predictor of TOT in three tasks using visual stimuli. We conclude (1) that age-related differences can often be attributed to cognitive factors involved in temporal-order perception, and (2) that the concept of temporal-order perception is more complex than implied by the current models.
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On duration judgments lasting seconds to minutes, which are thought to be cognitively mediated, women typically perceive time intervals as longer than men do. On a perceptual level in the milliseconds range, few reports indicate higher acuity of temporal processing in men than in women. In this study, sex differences in the perception of temporal order of two acoustic stimuli were identified in neurologically healthy subjects, as well as in brain-injured patients with lesions in either the left or the right hemisphere. Women needed longer interstimulus intervals than men before they were able to indicate the correct temporal order of two clicks. Neurobiological evidence and findings on cognitive strategies are discussed to explain the apparent psychophysical sex differences.
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The present study was conducted to demonstrate classic conditioning in electrodermal (ED) and heart rate (HR) responses by using a nonaversive reaction time (RT) task as unconditional stimulus (US). Three groups of 12 subjects each were studied to test the efficacy of this US procedure by varying the essential components of the RT task-US between groups. Eight seconds differential delay conditioning was applied in each group. Simple geometric features (square, cross) displayed on a TV screen were used as CS+ and CS-. RT task consisted of a nonaversive tone (72 dBA, 1000 or 1200 Hz) and a motor response (pressing a button with the left index finger). Subjects were asked to respond as soon as the tone stimulus was presented. The three groups received different stimulus sequences during the 16-trial acquisition phase only. In one group (Group C1), CS+ was followed by a tone to which subjects were to respond, whereas CS- was not followed by a tone. Similarly, in a second group (Group H), CS+ was followed by a tone, whereas CS- was not; however, subjects of Group H (habituation group) were not required to respond to the tone. In a third group, (Group C2) CS+ was followed by a tone to which subjects were to respond, while CS- was followed by a different tone requiring no response. According to analysis of Group C1 data, differential conditioning was obtained in each response measure. Group H displayed habituation in each response measure obtained. In Group C2, differential conditioning was obtained in the second latency window of ED responses only.(ABSTRACT TRUNCATED AT 250 WORDS)
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Eintragsart
Sprache
- Englisch (5)
Thema
- Acoustic Stimulation
- Adult (5)
- Age Factors (1)
- Aged (3)
- Aged, 80 and over (2)
- Aging/*psychology (1)
- Analysis of Variance (1)
- Aphasia/physiopathology/psychology (1)
- *Attention (1)
- Attention/physiology (1)
- *Auditory Perception/physiology (1)
- Beta oscillation (1)
- *Beta Rhythm (1)
- Brain Injury, Chronic/physiopathology/*psychology (1)
- Brain Mapping (1)
- Cerebral Cortex/physiopathology (1)
- Cerebral Infarction/physiopathology/psychology (1)
- *Cognition (2)
- Conditioning, Classical (1)
- Decision (1)
- *Decision Making (1)
- Dominance, Cerebral/physiology (1)
- Electric Conductivity (1)
- Event-related desynchronization (1)
- Female (5)
- *Gender Identity (1)
- Heart Rate (1)
- Humans (5)
- Intention (1)
- Male (5)
- *Memory, Short-Term (1)
- Middle Aged (4)
- *Movement (1)
- Photic Stimulation (2)
- Psychoacoustics (1)
- Psychomotor Performance (1)
- *Reaction Time (1)
- Reaction Time (1)
- Reference Values (1)
- Regression Analysis (1)
- *Sex Characteristics (1)
- Sex Factors (1)
- Skin (1)
- Task Performance and Analysis (1)
- Time Factors (1)
- *Time Perception (2)
- *Time Perception/physiology (1)
- Verbal Behavior (1)
- Volition (1)
- Young Adult (2)