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Spatiotemporal dynamics of the human brain associated with transitions in coordination timing

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Date Issued:
1995
Summary:
Recent studies have demonstrated that the strategy an individual uses to synchronize motor behavior (e.g. finger flexions) with externally delivered, periodic stimuli depends, in part, on the stimulus presentation rate (Mates, Muller, Radil, and Poppel, 1994; Engstrom, Kelso, and Holroyd, 1995). At rates slower than approximately 0.5 Hz, subjects typically exhibit a reactive-type coordination pattern where the response follows the stimulus by an order of magnitude consistent with typical response times (i.e. 150-250 milliseconds). At faster rates, however, subjects typically anticipate the impending stimulus in order to synchronize movement with it. In the present study, scalp electroencephalographic (EEG) signals (61 channels) were recorded during a sensorimotor task designed to investigate transitions from one coordination mode to another. We found that subjects exhibited a spontaneous transition from reactive to anticipatory behavior as the stimulus presentation rate increased past some critical frequency. A spatiotemporal analysis of the EEG signals accompanying this task revealed: (1) a widespread frequency component in the EEG matching that of both the stimulus and movement; (2) peak spectral power density over central and antero-central regions in both men and women during reactive behavior; (3) an additional bilaterally distributed frontal component at the most anterior portion of the scalp in men during anticipatory behavior; (4) an additional left fronto-central component which extended posteriorly toward antero-central regions in women during anticipatory behavior; (5) fluctuation enhancement in both the EEG spectral power density and the time lag ($\tau$) between the movement and stimulus accompanying the transition from reactive to anticipatory behavior; (6) that the spectral power density patterns obtained in the primary experimental condition (REACTIVE) were more similar in terms of their spatial distribution with a control condition in which subjects were asked to produce rhythmic movements without benefit of an external stimulus (MOTOR-ONLY) than with a control condition in which subjects passively watched a periodic visual stimulus (STIMULUS-ONLY); (7) that the spectral power density patterns obtained during reactive behavior in the primary experimental condition were more similar spatially to the MOTOR-ONLY condition than du ring anticipatory behavior; and finally (8) that the spectral power density patterns obtained during the experimental condition are not completely accounted for in terms of purely motor- or stimulus-related components. These results are discussed within a common framework of pattern formation instigated by dynamic instabilities in the human brain and behavior.
Title: Spatiotemporal dynamics of the human brain associated with transitions in coordination timing.
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Name(s): Wallenstein, Gene Vincent
Florida Atlantic University, Degree Grantor
Charles E. Schmidt College of Science
Center for Complex Systems and Brain Sciences
Type of Resource: text
Genre: Electronic Thesis Or Dissertation
Issuance: monographic
Date Issued: 1995
Publisher: Florida Atlantic University
Place of Publication: Boca Raton, Fla.
Physical Form: application/pdf
Extent: 257 p.
Language(s): English
Summary: Recent studies have demonstrated that the strategy an individual uses to synchronize motor behavior (e.g. finger flexions) with externally delivered, periodic stimuli depends, in part, on the stimulus presentation rate (Mates, Muller, Radil, and Poppel, 1994; Engstrom, Kelso, and Holroyd, 1995). At rates slower than approximately 0.5 Hz, subjects typically exhibit a reactive-type coordination pattern where the response follows the stimulus by an order of magnitude consistent with typical response times (i.e. 150-250 milliseconds). At faster rates, however, subjects typically anticipate the impending stimulus in order to synchronize movement with it. In the present study, scalp electroencephalographic (EEG) signals (61 channels) were recorded during a sensorimotor task designed to investigate transitions from one coordination mode to another. We found that subjects exhibited a spontaneous transition from reactive to anticipatory behavior as the stimulus presentation rate increased past some critical frequency. A spatiotemporal analysis of the EEG signals accompanying this task revealed: (1) a widespread frequency component in the EEG matching that of both the stimulus and movement; (2) peak spectral power density over central and antero-central regions in both men and women during reactive behavior; (3) an additional bilaterally distributed frontal component at the most anterior portion of the scalp in men during anticipatory behavior; (4) an additional left fronto-central component which extended posteriorly toward antero-central regions in women during anticipatory behavior; (5) fluctuation enhancement in both the EEG spectral power density and the time lag ($\tau$) between the movement and stimulus accompanying the transition from reactive to anticipatory behavior; (6) that the spectral power density patterns obtained in the primary experimental condition (REACTIVE) were more similar in terms of their spatial distribution with a control condition in which subjects were asked to produce rhythmic movements without benefit of an external stimulus (MOTOR-ONLY) than with a control condition in which subjects passively watched a periodic visual stimulus (STIMULUS-ONLY); (7) that the spectral power density patterns obtained during reactive behavior in the primary experimental condition were more similar spatially to the MOTOR-ONLY condition than du ring anticipatory behavior; and finally (8) that the spectral power density patterns obtained during the experimental condition are not completely accounted for in terms of purely motor- or stimulus-related components. These results are discussed within a common framework of pattern formation instigated by dynamic instabilities in the human brain and behavior.
Identifier: 12436 (digitool), FADT12436 (IID), fau:9331 (fedora)
Collection: FAU Electronic Theses and Dissertations Collection
Note(s): Advisers: J. A. Scott Kelso; Steven L. Bressler.
Thesis (Ph.D.)--Florida Atlantic University, 1995.
Subject(s): Biology, Neuroscience
Psychology, Psychobiology
Held by: Florida Atlantic University Libraries
Persistent Link to This Record: http://purl.flvc.org/fcla/dt/12436
Sublocation: Digital Library
Use and Reproduction: Copyright © is held by the author, with permission granted to Florida Atlantic University to digitize, archive and distribute this item for non-profit research and educational purposes. Any reuse of this item in excess of fair use or other copyright exemptions requires permission of the copyright holder.
Use and Reproduction: http://rightsstatements.org/vocab/InC/1.0/
Host Institution: FAU
Is Part of Series: Florida Atlantic University Digital Library Collections.