Experimental design

All the experiments were performed during the long-day photoperiod (lights on at 08:00 and off at 22:00). We induced transient reversible cognitive impairment by 8 h of total SD and spatial memory performance was measured using a circular platform test. In DON experiment 13 young animals (0.1mg/kg, n = 6; 1mg/kg, n = 7) and 13 aged animals (0.1mg/kg, n = 6; 1mg/kg, n = 7) were used. In MEM experiment, 13 young (0.1mg/kg, n = 6; 1mg/kg, n = 7) and 15 aged animals (0.1mg/kg, n = 7; 1mg/kg, n = 8) and in vehicle (Physiological saline) treated experiment 8 young and 6 aged animals were used. All the animals underwent training during day 1 (pre-SD session) and 8h of total SD was performed on day 2 followed by testing immediately after the SD challenge (post-SD session). DON, MEM or saline was injected intraperitoneally 3h before the end of the SD or before the onset of the cognitive function test (Fig 1).

White bar indicates the light-on period and black bar indicate the light-off period. Training started at 16:00 on day 1 and 8h of sleep deprivation (SD) started at 8:00 on day 2, the test was performed immediately after SD on day 2 and DON, MEM or Saline injected 3h before the test.