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Internal And External Triggers For Action, Shannon Matkovich

Theses and Dissertations (Comprehensive)

When the self paced preparation of an action is interrupted by a stimulus prompting the same motor response there is an increase in the reaction time to the stimulus as compared to an external or simple reaction time (SRT) condition (Obhi & Haggard, 2004). Previous studies have suggested that this cost is not attributable to perceptual or attentional factors. Therefore, to investigate the source of this RT cost we varied the motor demands of movements in Experiments one and two. Results indicated that the level of motor programming demands did not influence the RT cost in these experiments. While RTs …