Post-perceptual processing during the attentional blink is modulated by inter-trial task expectancies

Jocelyn L Sy,James C Elliott,Barry Giesbrecht

doi:10.3389/fnhum.2013.00627

Abstract

The selective processing of goal-relevant information depends on an attention system that can flexibly adapt to changing task demands and expectations. Evidence from visual search tasks indicates that the perceptual selectivity of attention increases when the bottom-up demands of the task increase and when the expectations about task demands engendered by trial history are violated. Evidence from studies of the attentional blink (AB), which measures the temporal dynamics of attention, also indicates that perceptual selectivity during the AB is increased if the bottom-up task demands are increased. The present work tested whether expectations about task demands engendered by trial history also modulate perceptual selectivity during the AB. Two experiments tested the extent to which inter-trial switches in task demands reduced post-perceptual processing of targets presented during the AB. Experiment 1 indexed post-perceptual processing using the event-related potential (ERP) technique to isolate the context sensitive N400 ERP component evoked by words presented during the AB. Experiment 2 indexed post-perceptual processing using behavioral performance to determine the extent to which personal names survive the AB. The results of both experiments revealed that both electrophysiological (Exp. 1) and behavioral (Exp. 2) indices of post-perceptual processing were attenuated when consecutive trials differed in terms of their perceptual demands. The results are consistent with the notion that the selectivity of attention during the AB is modulated not only by within-trial task demands, but also can be flexibly determined by trial-by-trial expectations.

Highlights

Human selective attention is often characterized as being flexible and dynamic, continually adapting to the information processing demands imposed by the external world and our internal goals and expectations (e.g., Corbetta and Shulman, 2002; Kastner and Pinsk, 2004; Vogel et al, 2005; Ristic and Giesbrecht, 2011; Franconeri et al, 2013)
Both the mere presence of an AB for one’s own name on switch trials and the fact that the severity of the AB for one’s own name can be modulated by intertrial task dependencies (i.e., AB magnitude was larger on switch relative to repeat trials) supports the idea that the post-perceptual processing of high priority stimuli can be attenuated during the AB by a violation of trial-by-trial expectancies generated during the course of one’s experience with a task
A final interesting finding is that while previous work has shown that increases in T1 task demands can cause an AB for one’s own name (Giesbrecht et al, 2009), the absence of an AB for one’s own name on repeat high load trials is suggestive evidence that the expectancies generated by inter-trial repetitions of high load are sufficient to override the effect of load on the current trial

Summary

Introduction

Human selective attention is often characterized as being flexible and dynamic, continually adapting to the information processing demands imposed by the external world and our internal goals and expectations (e.g., Corbetta and Shulman, 2002; Kastner and Pinsk, 2004; Vogel et al, 2005; Ristic and Giesbrecht, 2011; Franconeri et al, 2013). During visual search tasks in which difficulty varies from trial-to-trial, when the difficulty on trialn and trialn−1 are different (switch trials) the amount of interference caused by stimuli presented at task-irrelevant locations can be reduced compared to when the search difficulty on consecutive trials is the same (repeat trials, e.g., Theeuwes et al, 2004) Together these studies, as well as other similar behavioral and neuroimaging evidence (e.g., Yantis and Johnston, 1990; Handy et al, 2001; Yi et al, 2004), support the notion that the selectivity of spatial attention is not fixed, but rather flexibly adapts to both the inherent difficulty of the task as well as one’s expectations about the task

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