Pre-target oscillatory brain activity and the attentional blink

Abstract

Reporting the second of two targets within a stream of distracting words during rapid serial visual presentation (RSVP) is impaired when the targets are separated by a single distractor word, a deficit in temporal attention that has been referred to as the attentional blink (AB). Recent conceptual and empirical work has pointed to pre-target brain states as potential mediators of the AB effect. The current study examined differences in pre-target electrophysiology between correctly and incorrectly reported trials, considering amplitude and phase measures of alpha oscillations as well as the steady-state visual evoked potential (ssVEP) evoked by the RSVP stream. For incorrectly reported trials, relatively lower alpha-band power and greater ssVEP inter-trial phase locking were observed during extended time periods preceding presentation of the first target. These results suggest that facilitated processing of the pre-target distracter stream indexed by reduced alpha and heightened phase locking characterizes a dynamic brain state that predicts lower accuracy in terms of reporting the second target under strict temporal constraints. Findings align with hypotheses in which the AB effect is attributed to neurocognitive factors such as fluctuations in pre-target attention or to cognitive strategies applied at the trial level.

Keywords: Attention control; Electroencephalography (EEG); Oscillatory activity; Steady-state visual evoked potential (ssVEP); Visual rapid serial processing.

Fig. 1

The sequence of one trial of the RSVP paradigm. Items were presented for 116 ms each resulting in a presentation rate of 8.56 Hz. The present illustration depicts a trial in which the target words are separated by a single distractor word. Target words were neutrally valenced and displayed in a green font, whereas all distractor words were presented in a white font. All words were presented in the center of a computer screen

Fig. 2

Mean (n = 17) report accuracy for T2 on trials in which T1 was reported correctly for the Lag 2 (M = 60.72 %, SE = 3.69 %), Lag 4 (M = 86.06 %, SE = 2.30 %), and Lag 6 (M = 89.88 %, SE = 2.20 %) conditions. Standard errors are indicated by the vertical bars. A significant linear trend was observed across all three lag conditions

Fig. 3

Wavelet illustrations for ITPL (left, top), power (left, bottom), for frequencies 6.73–20.50 Hz from −1100 to 1104 ms relative to T1 onset from one representative sensor, with time periods of significant incorrect versus correct differences indicated by the black box. Topographical distribution of t values (right) taken at the time point containing the maximum t value

Fig. 4

Wavelet illustrations for ISPL taken from one representative sensor within the right frontal (left, top) and right parietal (left, bottom) for frequencies 6.73–20.50 Hz from −1100 to 1104 ms relative to T1 onset from one representative sensor, with time periods of significant incorrect versus correct differences indicated by the gray or black box. Topographical distribution of t values (right) taken at the time point containing the maximum t value for either sensor cluster

Fig. 5

a p values across time for incorrect versus correct comparison of ongoing phase for ssVEP (gray) and alpha (black) at one representative sensor. The black bar indicates the time window in which the p values exceeded significance. b Rose plots of the phase angle distribution for all correct (left, bottom) and incorrect trials (left, top) at one representative time point within the time window of significant alpha p values. The topographical distribution of p values of correct versus incorrect alpha phase angles at this time point is illustrated (right)

Fig. 6

Inter-individual relationship between alpha-power differences (correct–incorrect) and AB performance (Lag 4 % correct = Lag 2 % correct) from one representative sensor with a Spearman's Rho of −0.60 (p < 0.05). Spearman's Rho values across sensors illustrated in the topographical distribution