The present research utilized electrophysiological responses in the form of the event-related potential (ERPs) to measure the influence of expectation and motivation on visual orientation and attention. The ERPs were subsequently used to identify the involvement of specific brain structures engaged in the visual attention process. The research design is an adaptation of a modified Posner attention task originally published by Derryberry & Reed (1994). The work extended the findings of Derryberry & Reed (1994) while examining the neurological changes associated with orienting to positive or negative incentives. Cues preceded target locations in three horizontally lined boxes containing either positive or negative incentives. Speed and accuracy of responses determined whether an incentive was rewarded or removed. Two types of attention were studied: voluntary (effortful) and involuntary (automatic). Both forms of attention were altered by cues that were valid or invalid depending, in part, on the inter-stimulus-interval between cue and target. Two ERP components, P1 and N1, were extracted to investigate the differences in attention orientation. The results indicated that the N1 was sensitive to cue location. Cues that were presented in a location incongruent to the target location caused an increased response in the N1 amplitude. The N1 was generated by multiple sources in the medial temporal lobe, dorsal occipital lobe and the inferior parietal lobe. In contrast, an enhanced P1 effect occurred to targets that were presented in the negative incentive location. The larger P1 to negative target locations, generated in the dorsal occipital region, suggests that attention was oriented toward a location associated with losing points. This extends previous research that attention is oriented toward negative information. However, no effects were found in either the P1 or N1 response following positive or negative feedback. The results from all three analyses suggested that the N1 reflected the orientation of attention to invalid cues, while the P1 was sensitive to targets located in the negative incentive condition.
|School:||University of Louisville|
|School Location:||United States -- Kentucky|
|Source:||DAI-B 69/08, Dissertation Abstracts International|
|Subjects:||Psychobiology, Experimental psychology, Cognitive psychology|
|Keywords:||Attention, Brain, ERP, Incentives, Motivation, Reward, Selective attention, Visual attention|
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