title: Influence of age, circadian and homeostatic processes on inhibitory motor control: a Go/Nogo task study.
abstract: BACKGROUND
  The contribution of circadian system and sleep pressure influences on executive performance as a function of age has never been studied. The aim of our study was to determine the age-related evolution of inhibitory motor control (i.e., ability to suppress a prepotent motor response) and sustained attention under controlled high or low sleep pressure conditions.
  
  
  METHODS
  14 healthy young males (mean age = 23 ± 2.7; 20-29 years) and 11 healthy older males (mean age = 68 ± 1.4; 66-70 years) were recruited. The volunteers were placed for 40 hours in "constant routine". In the "Sleep Deprivation SD" condition, the volunteer was kept awake for 40 hours to obtain a high sleep pressure condition interacting with the circadian process. In the "NAP" condition, the volunteer adopted a short wake/sleep cycle (150/75 min) resulting in a low sleep pressure condition to counteract the homeostatic pressure and investigate the circadian process. Performances were evaluated by a simple reaction time task and a Go/Nogo task repeated every 3H45.
  
  
  RESULTS
  In the SD condition, inhibitory motor control (i.e., ability to inhibit an inappropriate response) was impaired by extended wakefulness equally in both age groups (P<.01). Sustained attention (i.e. ability to respond accurately to appropriate stimuli) on the executive task decreased under sleep deprivation in both groups, and even more in young participants (P<.05). In the NAP condition, age did not influence the time course of inhibitory motor control or sustained attention. In the SD and NAP conditions, older participants had a less fluctuating reaction time performance across time of day than young participants (P<.001).
  
  
  CONCLUSIONS
  Aging could be a protective factor against the effects of extended wakefulness especially on sustained attention failures due to an attenuation of sleep pressure with duration of time awake.
authors: CNRS USR 3413 SANPSY, Sleep, Attention and NeuroPSYchiatrie, Université de Bordeaux, Bordeaux, France. patricia.sagaspe@gmail.com
authors: Patricia
authors: P
authors: Sagaspe
authors: Jacques
authors: J
authors: Taillard
authors: Hélène
authors: H
authors: Amiéva
authors: Arnaud
authors: A
authors: Beck
authors: Olivier
authors: O
authors: Rascol
authors: Jean-François
authors: JF
authors: Dartigues
authors: Aurore
authors: A
authors: Capelli
authors: Pierre
authors: P
authors: Philip
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000375:Aging / Q000502:physiology / Q000523:psychology; D001288:Attention / Q000502:physiology*; D002940:Circadian Rhythm / Q000502:physiology*; D006706:Homeostasis / Q000502:physiology*; D006801:Humans; D008297:Male; D009483:Neuropsychological Tests; D011597:Psychomotor Performance / Q000502:physiology*; D011930:Reaction Time / Q000502:physiology; D012890:Sleep / Q000502:physiology; D012892:Sleep Deprivation / Q000503:physiopathology / Q000523:psychology*; D014851:Wakefulness / Q000502:physiology