Cardiac psychophysiological tuning to socioaffective content is disrupted in aged rhesus monkeys (Macaca mulatta).

Aging ushers in numerous disruptions to autonomic nervous system (ANS) function. Although the effects of aging on ANS function at rest are well characterized, there is surprising variation in reports of age-related differences in ANS reactivity to psychosocial stressors, with some reports of decreases and other reports of increases in reactivity with age. The sources of variation in age-related differences are largely unknown.

Causal analysis as a bridge between qualitative and quantitative research.

Yarkoni argues that one solution is to abandon quantitative methods for qualitative ones. While we agree that qualitative methods are undervalued, we argue that both are necessary for thoroughgoing psychological research, complementing one another through the use of causal analysis. We illustrate how directed acyclic graphs can bridge qualitative and quantitative methods, thereby fostering understanding between different psychological methodologies.

Tolerance of muzzle contact underpins the acquisition of foraging information in vervet monkeys (Chlorocebus pygerythrus).

Muzzle contact, where one animal brings its muzzle into close proximity to that of another, has often been hypothesized as a straightforward means of socially mediated food investigation. Using 2,707 observations of muzzle contact occurring across 3 troops of wild vervet monkeys (Chlorocebus pygerythrus), we tested this social learning hypothesis. We first explored the social structuring of muzzle contact by analyzing the characteristics of initiators and receivers.