Review articleThe role of brain reward pathways in stress resilience and health
Section snippets
The role of brain reward pathways for stress resilience and health
Although stress is related to increased health risks such as major depressive disorder and post-traumatic stress disorder (Cohen et al., 2007; Mcewen, 2004), most individuals are remarkably resilient (Bonanno, 2004). Resilience is defined as the capacity to adapt successfully to acute stress, trauma, or chronic adversity (Feder et al., 2009). Despite significant public interest in this area, we still know little about the neurobiological and behavioral mechanisms of resilience (Bonanno et al.,
Activating the reward system reduces stress physiology and behavior: experimental evidence
An organism’s survival depends on the ability to seek out and approach rewarding stimuli in the environment. Primary rewards are those that immediately influence survival, such as food and reproduction, whereas secondary rewards are those that may not directly impact survival but facilitate these survival behaviors, including money and positive social experiences (Berridge and Robinson, 2003; Schultz, 2015; Sescousse et al., 2013). Also key to survival is being able to successfully avoid or
Plausible neurobiological relationships between reward and stress resilience
The reward system is a well-characterized network of regions across the limbic, prefrontal, striatal and midbrain regions (Haber and Knutson, 2010), and neural activity in these regions is relatively consistent across primary and secondary reward types, as shown in a thoughtful review of this work (Sescousse et al., 2013). Like the reward system, the neurobiology of the brain’s fight-or-flight stress response system is well-characterized including regions in limbic, midbrain and prefrontal
Reward-stress resilience pathways: implications for health
If brain reward pathways confer stress resilience, one implication is that they could protect against stress-related health outcomes. It is well-established that stress can trigger the onset and exacerbation of a broad range of psychiatric disorders (e.g., depression, PTSD, addictive disorders) and physical health conditions (e.g., cardiovascular disease, cancer) (Cohen et al., 2007; Hammen, 2005; Jones and Barlow, 1990; Mcewen, 2004; McEwen and Gianaros, 2010; Sinha, 2008). Despite the promise
Discussion and future directions
Large independent literatures have focused on the reward and stress systems, yet much less attention has been paid to how these systems interact. Here, we describe exciting new research linking reward system activation with stress resilience, as well as initial links to stress-related health outcomes. We reviewed a range of human and animal studies linking reward system activation (and rewarding environments) with stress resilience effects (see Table 1). Consistent with this reward-stress
Conclusions
The findings presented here suggest that reward system activation can reduce behavioral and physiological responses to stress in both human and animal models. Neural, behavioral, and pharmacological studies support the neurobiological plausibility for reward-stress resilience effects, highlighting the role of connectivity between reward structures (such as VS and VMPFC) and structures that initiate physiological stress responding (hypothalamus and amygdala), as well as the role of opioids in
Author contributions
Both authors conceptualized and wrote the paper.
Financial disclosures
Both authors reported no financial interests or potential conflicts of interest
Acknowledgements
This work was supported by grants from the National Center for Complementary & Integrative Health (NCCIH) of the National Institutes of Health (NIH) (R21AT008493, R01AT008685) awarded to the last author. This funding source had no involvement in study design; data collection, analysis, or interpretation; writing of this report; or the decision to submit this article for publication. The content is solely the responsibility of the authors and does not necessarily represent the official views of
References (112)
- et al.
Systemic naloxone administration potentiates locus coeruleus noradrenergic neuronal activity under stressful but not non-stressful conditions
Brain Res.
(1988) - et al.
Oxytocin modulates dopamine-mediated reward in the rat subthalamic nucleus
Horm. Behav.
(2013) - et al.
Environmental enrichment lowers stress-responsive hormones in singly housed male and female rats
Pharmacol. Biochem. Behav.
(2003) - et al.
Studying brain-regulation of immunity with optogenetics and chemogenetics; A new experimental platform
Brain Behav. Immun.
(2017) - et al.
Parsing reward
Trends Neurosci.
(2003) - et al.
Interactions between sucrose, pain and isolation distress
Pharmacol. Biochem. Behav.
(1987) - et al.
Synaptology of prefrontal cortical projections to the basolateral amygdala: an electron microscopic study in the rat
Neurosci. Lett.
(1995) - et al.
The mesoaccumbens dopamine in coping with stress
Neurosci. Biobehav. Rev.
(2012) - et al.
“Snacking” causes long term attenuation of HPA axis stress responses and enhancement of brain FosB/deltaFosB expression in rats
Physiol. Behav.
(2011) - et al.
Role of endogenous opioid system in the regulation of the stress response
Prog. Neuropsychopharmacol. Biol. Psychiatry
(2001)