Psychosocial versus physiological stress - Meta-analyses on deactivations and activations of the neural correlates of stress reactions

Abstract

Stress is present in everyday life in various forms and situations. Two stressors frequently investigated are physiological and psychosocial stress. Besides similar subjective and hormonal responses, it has been suggested that they also share common neural substrates. The current study used activation-likelihood-estimation meta-analysis to test this assumption by integrating results of previous neuroimaging studies on stress processing. Reported results are cluster-level FWE corrected. The inferior frontal gyrus (IFG) and the anterior insula (AI) were the only regions that demonstrated overlapping activation for both stressors. Analysis of physiological stress showed consistent activation of cognitive and affective components of pain processing such as the insula, striatum, or the middle cingulate cortex. Contrarily, analysis across psychosocial stress revealed consistent activation of the right superior temporal gyrus and deactivation of the striatum. Notably, parts of the striatum appeared to be functionally specified: the dorsal striatum was activated in physiological stress, whereas the ventral striatum was deactivated in psychosocial stress. Additional functional connectivity and decoding analyses further characterized this functional heterogeneity and revealed higher associations of the dorsal striatum with motor regions and of the ventral striatum with reward processing. Based on our meta-analytic approach, activation of the IFG and the AI seems to indicate a global neural stress reaction. While physiological stress activates a motoric fight-or-flight reaction, during psychosocial stress attention is shifted towards emotion regulation and goal-directed behavior, and reward processing is reduced. Our results show the significance of differentiating physiological and psychosocial stress in neural engagement. Furthermore, the assessment of deactivations in addition to activations in stress research is highly recommended.

Keywords: Achievement stress; IFG; Insula; Pain; Social exclusion; Striatum.

Figure 1. Activations for physiological and psychosocial stress

Contrasts showing stronger convergence in activation in psychosocial stress than in physiological stress (red) and stronger convergence in activation in physiological stress than in psychosocial stress (blue). (Abbreviations: L=left; R=right; BIL=bilateral; INS=insula; IFG=inferior frontal gyrus; ROP=rolandic operculum; MCC=middle cingulate gyrus; MFG=middle frontal gyrus; TH=thalamus; CEREB=cerebellum; PUT=putamen; SMG=supramarginal gyrus; STG=superior temporal gyrus.) Results are cluster-level FWE corrected (p<.05).

Figure 2. Conjunction of activations

Conjunction of the results of the meta-analysis on activation in psychosocial stress and the one on activation in physiological stress revealing a cluster in the right inferior frontal gyrus (IFG) extending into the anterior insula (AI). Results are cluster-level FWE corrected (p<.05).

Figure 3. Deactivations for physiological and psychosocial stress

Contrasts showing stronger convergence in deactivation in psychosocial stress than in physiological stress (red) and stronger convergence in deactivation in physiological stress than in psychosocial stress (blue). (Abbreviations: L=left; R=right; CN=caudate nucleus; PL=paracentral lobule.) Results are cluster-level FWE corrected (p<.05).

Figure 4. Dorsal and ventral striatum in stress processing

A) Contrasts showing convergence of deactivation in psychosocial in the ventral striatum (red) and activation in physiological stress in the dorsal striatum (blue). B) Regions showing functional resting-state connectivity with the ventral (red) and the dorsal (blue) striatum. C) Likelihood ratio for significant behavioral domains (graphs in the upper panel) and paradigm classes (graphs in the lower panel) for the ventral (red) and the dorsal (blue) striatum for the forward inference approach.