title: Individual differences in cortisol responses to fear and frustration during middle childhood.
abstract: The purpose of this study was to examine individual differences in the activation and regulation of the hypothalamic-pituitary-adrenal (HPA) axis in prepubertal children after exposure to two different stress modalities and to evaluate the utility of an individual differences approach to the examination of HPA axis functioning. After a 30-min controlled baseline period, 73 7-year-olds (40 boys and 33 girls) were randomly assigned to a validity check condition or one of two experimental tasks designed to elicit fear or frustration. This was followed by a 60-min controlled regulation phase. A total of 17 saliva samples were collected, including 12 poststress samples at 5-min intervals. There was a significant stress modality effect, with children exposed to the fear condition reaching peak cortisol levels at 25min poststress and those exposed to the frustration condition reaching peak levels at 45min poststress. There was no difference in peak cortisol levels between the stress modalities. Individual variability across conditions was significant, with participants reaching peak levels as early as 10min poststress and as late as 60min poststress. Our data suggest that analysis of individual curves prior to making group-level comparisons may improve the explanatory power of HPA axis behavior models.
authors.affiliation: Department of Psychology, University of Michigan, Ann Arbor, MI 48109, USA. nestorl@umich.edu
authors.forename: Nestor L
authors.initials: NL
authors.lastname: Lopez-Duran
authors.forename: Nastassia J
authors.initials: NJ
authors.lastname: Hajal
authors.forename: Sheryl L
authors.initials: SL
authors.lastname: Olson
authors.forename: Barbara T
authors.initials: BT
authors.lastname: Felt
authors.forename: Delia M
authors.initials: DM
authors.lastname: Vazquez
mesh_terms: D002648:Child; D005239:Fear / Q000523:psychology; D005260:Female; D005639:Frustration; D006801:Humans; D006854:Hydrocortisone / Q000378:metabolism*; D007030:Hypothalamo-Hypophyseal System / Q000378:metabolism* / Q000503:physiopathology; D007206:Individuality; D008297:Male; D009483:Neuropsychological Tests; D010913:Pituitary-Adrenal System / Q000378:metabolism* / Q000503:physiopathology; D012463:Saliva / Q000378:metabolism; D013315:Stress, Psychological / Q000378:metabolism*; D013997:Time Factors
chemical_list: D006854:Hydrocortisone