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The restorative effect of naps on perceptual deterioration


Human performance on visual texture discrimination tasks improves slowly (over days) in the absence of additional training. This 'slow learning' requires nocturnal sleep after training and is limited to the region of visual space in which training occurred. Here, we tested human subjects four times in one day and found that with repeated, within-day testing, perceptual thresholds actually increased progressively across the four test sessions. This performance deterioration was prevented either by shifting the target stimuli to an untrained region of visual space or by having the subjects take a mid-day nap between the second and third sessions.

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Figure 1: Beneficial effect of napping.
Figure 2: Comparison of test-day and baseline long naps.
Figure 3: Beneficial effect of shifting stimulus location.


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This research was supported by grants from the National Institutes of Health (MH 48,832 and NS 26,985) and AFOSR (83-0320) and by fellowships to J.L.C. and M.A. from the Spanish Ministry of Education and the NATO Scientific Program, respectively.

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Correspondence to Sara C. Mednick.

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Mednick, S., Nakayama, K., Cantero, J. et al. The restorative effect of naps on perceptual deterioration. Nat Neurosci 5, 677–681 (2002).

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