Enhanced fear recall and emotional arousal in rats recovering from chronic variable stress
Emergence of posttraumatic-like behaviors following chronic trauma is of interest given the rising prevalence of combat-related posttraumatic stress disorder (PTSD). Stress associated with combat usually involves chronic traumatization, composed of multiple, single episode events occurring in an unpredictable fashion. In this study, we investigated whether rats recovering from repeated trauma in the form of chronic […]
Heterogeneity of neuroendocrine stress responses in aging rat strains
Hyperactivity of the hypothalamo-pituitary-adrenocortical (HPA) axis is linked with age-related decrements in cognition and neuronal survival. However, the nature and extent of age-related HPA axis deficits vary considerably across and indeed, within strains. The current study was designed to assess variance in HPA axis function using two rodent models commonly used in aging studies: Fischer […]
Effect of a cage divider permitting social stimuli on stress and food intake in rats
The need to obtain data from individual laboratory animals has forced many researchers to singly-house small animals. This is costly to the researcher and isolation can adversely affect animal physiology and behavior which in turn may threaten the validity and generalization of experiment results to humans. We assessed the practical use of a housing device […]
Robust behavioral effects of song playback in the absence of testosterone or corticosterone release
Some species of songbirds elevate testosterone in response to territorial intrusions while others do not. The search for a general explanation for this interspecific variation in hormonal response to social challenges has been impeded by methodological differences among studies. We asked whether song playback alone is sufficient to bring about elevation in testosterone or corticosterone […]
Behavioral responses to social separation stressor change across development and are dynamically related to HPA activity in marmosets
Psychosocial stressors activate two distinct stress–response systems, a central, behavioral response, and a peripheral, endocrine response. Both behavioral and endocrine responses to stressors are subject to individual and developmental variables, but it is not known whether stressor induced behaviors are stable across development, and how they correspond with changes in the endocrine component of the […]
Effects of early life adversity on cortisol/salivary alpha-amylase symmetry in free-ranging juvenile rhesus macaques
Early life adversity (ELA) affects physiological and behavioral development. One key component is the relationship between the developing Hypothalamic-Pituitary-Adrenal (HPA) axis and the Sympathetic Nervous System (SNS). Recent studies suggest a relationship between early life adversity and asymmetry in cortisol (a measure of HPA activation) and salivary alpha-amylase (sAA: a correlate of SNS activation) responses […]