Variable Normal sleep Shallow

Figure 1. Breakdown of the memory performance for the declarative and implicit tasks. left panel: Subjects having undergone sleep manipulation show a significantly reduced number of true positive responses and an increase in the false negative responses (forgotten items). The absence of differences in the true negative and false positive categories indicates that the memory performance after shallow sleep is characterized by increased forgetting rather than adopting a different response strategy (error bars: standard errors of the mean). right panel: Average reaction time differences for the blocks of random and fixed sequences in the SRT task. The graphs show that the fixed sequences have a ~40 millisecond performance improvement relative to the random sequences. This learning effect, in the absence of awareness of the fixed sequence, does not differ between the two sleep conditions.