Functional imaging reveals working memory and attention interact to produce the attentional blink

Abstract

If two centrally presented visual stimuli occur within approximately half a second of each other, the second target often fails to be reported correctly. This effect, called the attentional blink (AB; Raymond, J. E., Shapiro, K. L., & Arnell, K. M. Temporary suppression of visual processing in an RSVP task: An attentional blink? Journal of Experimental Psychology, Human Perception and Performance, 18, 849-860, 1992], has been attributed to a resource "bottleneck," likely arising as a failure of attention during encoding into or retrieval from visual working memory (WM). Here we present participants with a hybrid WM-AB study while they undergo fMRI to provide insight into the neural underpinnings of this bottleneck. Consistent with a WM-based bottleneck account, fronto-parietal brain areas exhibited a WM load-dependent modulation of neural responses during the AB task. These results are consistent with the view that WM and attention share a capacity-limited resource and provide insight into the neural structures that underlie resource allocation in tasks requiring joint use of WM and attention.

Figure 1

Schematic of the AB–WM trial procedure.

Figure 2

Behavioral results of the AB–WM experiment, shown are overall T1 accuracy as a function of WM load (left) and T2 accuracy, conditional on correct T1, as a function of WM load (right). Each mean is shown with its associated SE.

Figure 3

Areas active in the functional imaging data in the AB × WM Load interaction shown overlaid on the average of all participant’s anatomical images. Areas shown are the clusters located in the SPL/IPL boundary and MFG and a cluster in the fusiform gyrus.

Figure 4

A graph of the mean beta values in examplar regions, fusiform gyrus (FG; 29 −74 −2), MFG (−43 44 20), middle temporal gyrus (MTG; 49 −39 5), and SPL/IPL (27 −64 21).

Figure 5

Nine axial slices show the areas responsive to the contrast of WM Load (red), AB (blue), and the interaction of WM Load × AB (green). Overlap between areas active in each condition is denoted through color additions according to the red–green–blue system (e.g., yellow: overlap between WM Load [red] and WM Load × Interaction [green]).