Target-distractor interference in the attentional blink implicates the locus coeruleus-norepinephrine system

We provide evidence that the locus coeruleus-norephinephrine (LC-NE) system is the neurophysiological basis of the attentional blink. The attentional blink refers to decreased accuracy for reporting the second of two targets in a rapid serial visual presentation of distractors. The LC-NE account of the attentional blink posits that targets elicit a facilitative LC-NE system response that is available for the first target but subsequently unavailable to the second, due to the autoinhibitory nature of the LC-NE system. We propose a modification of the LC-NE account, suggesting that the LC-NE system response is elicited by interference between mutually exclusive responses demanded by temporally proximal targets and distractors. We increased the interference between the first target and the following distractor by reducing the time between them. For identifying the second target this high-interference condition yielded a benefit up to 200 msec after onset of the first, followed by a decrease in accuracy. Consistent with our modification of the LC-NE account, this result suggests a temporarily enhanced LC-NE system response to increased target-distractor interference.