Changes in cognitive processing following short-term cumulative partial sleep deprivation and recovery oversleeping

The effects on cognitive processing of 1 and 5 cumulative nights of partial sleep deprivation (PSD) and 1 and 2 nights of subsequent recovery oversleep was studied using an anagrams test and the Wisconsin Card Sorting Test. Seven paid undergraduate volunteers (5 male; 2 female) aged 18–23 who had normative 6.5–8.0 hr sleep patterns participated. They followed an 8-day schedule of morning and afternoon testing sessions consisting of 2 days in each of the experimental conditions: prebase-line, PSD, recovery sleep, and postbaseline. Sleep duration was calculated relative to individual habitual by subtracting 40% per night (PSD) and adding 40% and 20%, respectively (recovery sleep). On the anagrams test, results showed exaggerated time of day differences during both sleep manipulation conditions. Card-sorting performance was characterized by lesser efficiency of cognitive strategies (> non-perseverative errors) during recovery sleep and tendency towards perseveration with sleep loss. Results were discussed with particular reference to hypothesized neural substrates and clinical implications.