title: Cortisol awakening response and spatial working memory in man: a U-shaped relationship.
abstract: OBJECTIVE
  The association between hypothalamic-pituitary-adrenal (HPA)-axis function and cognition has long been investigated. An inverted U-shaped relationship has been described between various measures of HPA-axis function and neuropsychological performance in animals and man. Work with glucocorticoid receptor manipulation has corroborated these findings, with particular effects observed in relation to spatial working memory (SWM). As HPA-axis dysfunction is frequently found in patients with psychiatric illness, research in this area has potential implications for the treatment of the commonly observed cognitive impairment in such disorders. Here, we present the results of a pilot study examining the relationship between cortisol awakening response (CAR) and cognitive functions known to be susceptible to HPA-axis manipulation.
  
  
  METHODS
  Nineteen healthy male volunteers were recruited, and their CAR and performance in a task of SWM were assessed.
  
  
  RESULTS
  A highly significant quadratic relationship was observed between the CAR and SWM error rate (R(2)=0.63, p=0.001).
  
  
  CONCLUSIONS
  We provide novel evidence supporting the existence of an inverted U-shaped relationship between corticosteroid levels and cognitive function in humans.
authors.affiliation: Institute of Neuroscience, Newcastle University, Academic Psychiatry, Campus for Ageing and Vitality, Newcastle upon Tyne, UK.
authors.forename: Andrew S
authors.initials: AS
authors.lastname: Moriarty
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Bradley
authors.forename: Kirstie N
authors.initials: KN
authors.lastname: Anderson
authors.forename: Stuart
authors.initials: S
authors.lastname: Watson
authors.forename: Peter
authors.initials: P
authors.lastname: Gallagher
authors.forename: R Hamish
authors.initials: RH
authors.lastname: McAllister-Williams
mesh_terms: D000328:Adult; D019540:Area Under Curve; D001288:Attention / Q000502:physiology; D002940:Circadian Rhythm / Q000502:physiology*; D006801:Humans; D006854:Hydrocortisone / Q000378:metabolism*; D008297:Male; D008570:Memory, Short-Term / Q000502:physiology*; D008875:Middle Aged; D009483:Neuropsychological Tests; D010865:Pilot Projects; D011863:Radioimmunoassay; D012044:Regression Analysis; D012463:Saliva / Q000378:metabolism*; D065852:Spatial Memory / Q000502:physiology*; D014851:Wakefulness / Q000502:physiology*
chemical_list: D006854:Hydrocortisone
keywords: HPA-axis; cognition; corticosteroids; cortisol; cortisol awakening response; spatial working memory