Attention and motor control Sample Clauses

Attention and motor control. Whether conscious perception is seen as the opponent computation of attention the question that holds here is in which situations may attention optimize the motor performance and in which situations attention cannot be used in this way and thus, conscious perception is required to maintain acceptable level of motor performance? It has been largely accepted since the precursor work of Xxxxxx that cues provided in a valid way, i.e., before the appearance of a target, lead to observed facilitation effects in the participants reaction times. Cues can be endogenous or exogenous. In the first case, while the targets are presented in the left or right visual hemifields, the cue is provided at the center of the screen and indi- cates where the target will potentially appear. In the second case the cues are directly and briefly displayed at the future location of appearance of the target. Both types of cues reveal facilitation effects on the participants’ performances through the orientation of attention to the target position that required pro- cessing. In a study by Xxxxxxx (1981), it was further demonstrated that cues provided at the spatial location of the target (exogenous cues) invariably and automatically attract attention while cues provided centrally (endogenous cues) affect attention depending on the participant’s desire to use the cue. Indeed, in this study, participants were asked to search for a letter (L or R) among an array of eight letters arranged in a circle. When the letter was found, their task was to press the corresponding left or right button. Arrowhead cues were used to orient attention in an endogenous way (the central cue was placed at the level of the fixation point); flashed cues placed to the right or to the left close to the target letters were used to attract attention in an exogenous way. Both cues could be valid or invalid. Two groups of participants did the experiment, i.e. the “attend” group, which was asked to focus attention on the cues, and the “ignore” group that was asked to ignore the cues. Distinct effects were reported on reaction times: while in the “attend group”, substantial effects of cue validity were reported for both types of cues, in the “ignore group” effects of cue validity was reported for the exogenous cues only. These results suggest that endoge- nous cues are effective only when participants voluntarily focus attention on the task; exogenous cues that are displayed close to the stimulus capture attention auto...