Abstract
Purpose: Attentional blink (AB) refers to people's inability to detect and identify the second of two targets presented in close temporal succession, typically in a rapid serial visual presentation (RSVP) stream. Is the attentional mechanism governing the temporal selection of sensory information the same or different between foveal and peripheral vision? Here we assess the temporal dynamics of attention in foveal versus peripheral vision using the AB paradigm. Method: Six normally sighted young adults participated in each of the two experiments (E1 and E2). RSVP streams of 24 distractor letters with two target letters (T1 and T2) of a different color periodically embedded within them were presented at a rate of 9.44 Hz in foveal or in peripheral vision. Eccentricities of stimuli in the peripheral condition were 4.0° (E1) and 8.0° (E2) in lower right visual field. The stimuli subtended visual angle of about 1.3° and 2.6° (E1), and 0.5° and 3.0° (E2) in the foveal and peripheral conditions, respectively. Foveal and peripheral trials were presented in separate blocks (4 blocks per condition) of 80 trials. Results: Analysis of the proportion of correct T2 reports given correct T1 identification, P(T2|T1), showed the typical AB findings in both the foveal and peripheral conditions. Inverted Gaussian functions were fitted to the P(T2|T1) data to estimate the magnitude of the AB effects. Average magnitudes of AB in the foveal and peripheral conditions were 0.73±0.06 and 0.46±0.07 (E1), and 0.57±0.08 and 0.34±0.08 (E2), respectively. Magnitude of AB was significantly smaller in peripheral than in foveal vision in both experiments (ps<.05). Conclusion: The results appear to suggest a weaker temporary reduction in attention in peripheral than in foveal vision during AB. The findings taken together may imply systematic temporal variations in selective attentional deployment across the visual field as a function of eccentricity.