The attentional blink (AB) is a deficit in detecting a second target (T2) when it appears within approximately 200-500 milliseconds of a first target (T1) in a rapid serial visual presentation (RSVP) stream. Discovered by Jane Raymond, Kimron Shapiro, and Karen Arnell (1992), the AB reveals a fundamental bottleneck in temporal attention: the act of processing one target temporarily impairs the ability to process the next.
The Basic Phenomenon
In the typical RSVP paradigm, items (usually letters or digits) are presented one at a time at fixation at a rate of about 10 per second. Observers must identify two targets embedded in the stream (e.g., two letters among digit distractors). When T2 appears within 200-500 ms of T1, T2 identification is severely impaired. At very short lags (within ~100 ms, called "Lag 1 sparing"), T2 is often spared, suggesting the two targets are processed within the same attentional episode.
Theories of the Attentional Blink
Multiple theories have been proposed. The two-stage model (Chun and Potter, 1995) proposes that targets are first detected rapidly (Stage 1) but require a slower, capacity-limited consolidation process (Stage 2) to be consciously reported. While T1 occupies Stage 2, T2's fleeting Stage 1 representation decays before it can be consolidated. The temporary loss of control hypothesis (Di Lollo) proposes that the AB reflects a failure of the attentional filter configuration when T1 processing disrupts the executive control settings.
Emotionally significant stimuli can escape the attentional blink. Anderson (2005) showed that emotionally arousing words were less susceptible to the AB than neutral words. Similarly, threat-relevant stimuli (angry faces, spiders) are detected more efficiently during the blink period. This suggests that emotional significance provides a processing advantage that can overcome the temporal bottleneck, possibly through amygdala-mediated enhancement of target representations.
Individual Differences
The magnitude of the attentional blink varies substantially across individuals. Some people show virtually no blink, while others show a profound deficit. Individual differences correlate with working memory capacity, executive function, and even meditation experience — experienced meditators show a reduced AB, suggesting that attentional training can modulate the temporal bottleneck.
Neural Correlates
ERP studies show that "blinked" T2 items that are not consciously perceived still elicit early sensory processing (N1, P1 components) but fail to elicit the P3b component associated with conscious awareness and working memory consolidation. This neural evidence supports two-stage models: T2 is processed perceptually even during the blink but fails to reach the consolidation stage necessary for conscious report.