Editors' ChoiceCircadian Biology

The Sun Rises (and Sets) on Hamster Memories

Sci. Signal.  18 Nov 2014:
Vol. 7, Issue 352, pp. ec322
DOI: 10.1126/scisignal.aaa2976

Internal circadian clocks set a rhythm to which biological systems beat. In addition to regulating sleep and wake cycles, the circadian system influences learning and memory. Using Siberian hamsters as a model, Fernandez et al. evaluated the role of the part of the brain that regulates the circadian cycle, the suprachiasmatic nucleus (SCN), in altered memory processing when circadian rhythms are disrupted. As expected, animals with disrupted rhythms had recognition and spatial memory impairments. However, when the animals' SCN was disconnected, these memory deficits were reversed. Thus, memory impairment resulting from circadian dysfunction is dependent on preserving SCN circuit connections.

F. Fernandez, D. Lu, P. Ha, P. Costacurta, R. Chavez, H. C. Heller, N. F. Ruby, Dysrhythmia in the suprachiasmatic nucleus inhibits memory processing. Science 346, 854–857 (2014). [Abstract] [Full Text]