Sleep modulates temporal attention

The ability to allocate attentional resources in time is limited. In the attentional blink (AB) phenomenon, detection of the second of two targets that appear in close temporal succession is impaired (Martens & Wyble, 2010). Previous research suggests that the AB is reduced after days of practice (Maki & Padmanabhan, 1994), but not after four consecutive blocks within one session (Taatgen et al., 2009). Here we investigate the role of sleep in modulating practice-dependent changes in the AB. We used a rapid serial visual presentation (RSVP) display comprising a stream of 26 English letters presented at 12 items/s. Two of the letters were targets cued by an annulus, and the number of items between the first target (T1) and second target (T2) was varied to yield a lag of 2, 5 or 10 items. Participants reported which two letters they thought were cued, and no feedback was provided. Participants completed four sessions of the task at 9am, 12pm, 3pm and 5pm. At 1pm, half the participants took a polysomnographically-recorded nap for 60-90min, while the other participants went about their normal daytime activities. We observed increased T2 accuracy across sessions only within the nap group, and only for lag 2. The magnitude of improvement correlated positively with proportion of light stage two sleep, and negatively with proportion of deeper slow-wave sleep. We estimated the efficacy (probability of reporting a T2-relevant item), latency and precision of attentional selection using a mixture model that considered the serial position of non-target items mistakenly reported as T2. These analyses indicated that the improvement observed in the nap group was due to increased efficacy, with no change in latency or temporal precision. Our results suggest that sleep, particularly stage two sleep, improves temporal attention.