Original Research Article
Event related potentials reveal that increasing perceptual load leads to increased responses for target stimuli and decreased responses for irrelevant stimuli
1 Department of Communication Sciences and Disorders, University of South Carolina, USA
2 Department of Psychology, University of Hull, UK
3 School of Psychology, University of Aberdeen, UK
4 School of Psychology, University of Aberdeen, UK
5 Department of Psychology, University of South Carolina, USA
2 Department of Psychology, University of Hull, UK
3 School of Psychology, University of Aberdeen, UK
4 School of Psychology, University of Aberdeen, UK
5 Department of Psychology, University of South Carolina, USA
Lavie and colleagues (1995, JEP:HPP 9: 497-) have suggested that perceptual processing is influenced by perceptual load. Specifically, relevant information receives additional processing in high load situations exhausting the available capacity. On the other hand, irrelevant information receives less processing with increasing load on a relevant task, as there is a reduced amount of residual processing available. Rees et al. (1997, Science 278: 1616-) provided the first physiological evidence for this model, showing this pattern in a functional magnetic resonance imaging (fMRI) study. Likewise, Handy et al. (2001, Psych Sci 12: 213-) offered supporting evidence measuring event related potentials (ERPs). Both of these studies presented irrelevant information in peripheral vision. Here we manipulated load while using the identical stimuli and the same task (a peripheral gap judgment task) with centrally presented irrelevant stimuli. Event related potentials show the pattern predicted by Lavie and colleagues, specifically for the N1 component. This work offers further evidence that visual attention modulates relatively early processing of perceptual information. Specifically, increasing load resulted in stronger N1 responses to relevant information and weaker N1 responses to irrelevant information.
Keywords: human, perception, spatial attention, perceptual load
Copyright: © 2008 Rorden, Guerrini, Swainson, Lazzeri and Baylis. This is an open-access article subject to an exclusive license agreement between the authors and the Frontiers Research Foundation, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are credited.
*Correspondence: Chris Rorden, University of South Carolina,Columbia, SC 29208, USA. Tel: +1 803 777 9241. e-mail: rorden@gwm.sc.edu
Citation: Rorden C, Guerrini C, Swainson R, Lazzeri M and Baylis GC (2008) Event related potentials reveal that increasing perceptual load leads to increased responses for target stimuli and decreased responses for irrelevant stimuli. Front. Hum. Neurosci. (2008) 2:4. doi:10.3389/neuro.09.004.2008
Received: 13 March 2008; paper pending published: 10 April 2008; accepted: 05 May 2008; published online: 23 May 2008.
Edited by:
Kenneth Hugdahl, University of Bergen, Norway
Reviewed by:
Stefan Pollmann, Otto-von-Guericke-University, Germany
Kimmo A. Alho, University of Helsinki, Finland
Kimmo A. Alho, University of Helsinki, Finland
*Correspondence: Chris Rorden, University of South Carolina,Columbia, SC 29208, USA. Tel: +1 803 777 9241. e-mail: rorden@gwm.sc.edu
