Event-Related Desynchronization of Spontaneous Rhythm Caused by Anticipation of Collision
-
1
Hokkaido University, Japan
-
2
Tokyo Denki University, Japan
Animals, including human beings, subconsciously evade collisions. We have been investigating endogenous brain activity by MEG when humans anticipate a collision or intend to take evasive action. A form that expands rapidly while maintaining shape is recognized as a collision [1]. We presented participants with a collision-simulating image with a prior cue signal. Here we report results showing how spontaneous brain activity is modified by anticipation of a collision. MEG signals were recorded with a 76-ch helmet system (Elekta-Neuromag, custom-type) from 11 healthy male volunteers (24.9±3.9 years old). Each participant was presented with a visual collision-simulating stimulus in which a black indeterminate form expanded on a grey background in 170 ms (A: collision stimulus). As controls, two kinds of stimuli were presented. One was a uniform background, the brightness of which decreased with time to darkness (B: darkening stimulus), and the other was the black indeterminate form that changed in size in a random manner (C: random stimulus). A cue stimulus was given visually two seconds before each (A, B, or C) stimulus to enable the participant to anticipate the coming stimulus. One experimental session included 120 epochs per stimulus, in random order. Amplitude of spontaneous alpha band (8-13 Hz) rhythm decreased just after the onset of each stimulus and increased dramatically 400 ms later. The most notable result was that the amplitude of alpha rhythm before the collision stimulus (A) was significantly smaller than that before each control stimulus (B or C) (p<0.05) during the period between cue and stimulus. This result suggests that spontaneous brain activity in the alpha band is reduced by anticipating a negative (dangerous) event, possibly to prepare evasive action.
References
1. Lee DN. (1976) A theory of visual control of braking based on information about time-to-collision. Perception 5: 437-59.
Conference:
Biomag 2010 - 17th International Conference on Biomagnetism , Dubrovnik, Croatia, 28 Mar - 1 Apr, 2010.
Presentation Type:
Poster Presentation
Topic:
Neurocognition and Functional Connectivity
Citation:
Aoyama
G,
Yokosawa
K,
Kuriki
S and
Takahashi
M
(2010). Event-Related Desynchronization of Spontaneous Rhythm Caused by Anticipation of Collision.
Front. Neurosci.
Conference Abstract:
Biomag 2010 - 17th International Conference on Biomagnetism .
doi: 10.3389/conf.fnins.2010.06.00241
Copyright:
The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers.
They are made available through the Frontiers publishing platform as a service to conference organizers and presenters.
The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated.
Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed.
For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions.
Received:
31 Mar 2010;
Published Online:
31 Mar 2010.
*
Correspondence:
Gakuto Aoyama, Hokkaido University, Sapporo, Japan, aoga@ist.hokudai.ac.jp