PER3(5/5) show a greater cognitive decline, and a greater reduction in fMRI-assessed brain responses to an executive task, in response to total sleep deprivation.
The variable number tandem repeat (VNTR) polymorphism 5-repeat allele of the circadian gene PERIOD3 (PER3(5/5)) has been associated with cognitive decline at a specific circadian phase in response to a night of total sleep deprivation (TSD), relative to the 4-repeat allele (PER3(4/4)).
Overall, these findings enhance our understanding on the gene-brain interaction in aging, and may have further implications for the detection of subclinical cognitive decline associated with PER3 genotypes in late life.