The beneficial effect of concurrent task-irrelevant mental activity on temporal attention

It is believed that the human cognitive system is fundamentally limited in deploying attention over time. This limitation is reflected in the attentional blink, the impaired ability to identify the second of two visual targets presented in close succession. We report the paradoxical finding that the attentional blink is significantly ameliorated when observers are concurrently engaged in distracting mental activity, such as free-associating on a task-irrelevant theme or listening to music. This finding raises questions about the fundamental nature of the attentional blink, and suggests that the temporal dynamics of attention are determined by task circumstances that induce either a more or a less distributed state of mind.     

Decision making, the P3, and the locus coeruleus-norepinephrine system

Psychologists and neuroscientists have had a long-standing interest in the P3, a prominent component of the event-related brain potential. This review aims to integrate knowledge regarding the neural basis of the P3 and to elucidate its functional role in information processing. The authors review evidence suggesting that the P3 reflects phasic activity of the neuromodulatory locus coeruleus-norepinephrine (LC-NE) system. They discuss the P3 literature in the light of empirical findings and a recent theory regarding the information-processing function of the LC-NE phasic response. The theoretical framework emerging from this research synthesis suggests that the P3 reflects the response of the LC-NE system to the outcome of internal decision-making processes and the consequent effects of noradrenergic potentiation of information processing.