Latency shifts in early event-related potentials in a crossmodal attention task
Poster Presentation

Jonas Vibell
Department of Psychology, Oxford University

Corinna Klinge
Department of Psychology, Oxford University; Goettingen University, Germany

Massimiliano Zampini
Department of Psychology, Oxford University; Department of Cognitive Sciences and Education, University of Trento, Italy

Charles Spence
Department of Psychology, Oxford University

Anna C Nobre
Department of Psychology, Oxford University

     Abstract ID Number: 139
     Full text: Not available
     Last modified: March 21, 2005

Abstract
Behavioural studies have shown that attended stimuli are reported as occurring relatively earlier than unattended stimuli in temporal order judgement tasks. The nature of this effect, however, is not well characterised. The prior-entry effect could reflect modulation of early perceptual analysis of stimuli, as has been observed in spatial attention tasks, or it could reflect differential weighting of task relevant versus irrelevant information at decision-making or response stages. We used event-related potentials to test whether attention directed to the visual or tactile modality modulates perceptual and/or post-perceptual analysis during a temporal-order judgement task. During each trial visual and/or tactile stimuli were presented, one to each hand with different stimulus onset asynchronies. Trials could be unimodal (two stimuli in the same modality) or bimodal. The participant decided whether the stimulus presented on the left or on the right occurred first. During experimental blocks, attention was directed to either the visual or the tactile modality by a higher frequency of visual or tactile unimodal trials respectively. ERPs revealed that directing attention to vision significantly decreased the latency of the visual P1 component, showing that prior-entry during temporal-order judgement tasks is accompanied by changes in the timing of early perceptual analysis of stimuli.