Psychobiological Mechanisms of Resilience and Vulnerability: Implications for Successful Adaptation to Extreme Stress
Charney DS;
Commented by , 23 Feb 2004
Aims of the study
To identify the current evidence for the involvement of a number of neurochemicals and major psychobiological mechanisms in the resilience and vulnerability to extreme stress.
Method
This is a review of data on neurochemicals (neurotranmittors, neuropeptides, and hormones) and neural mechanisms that have been linked to the psychobiological response to extreme stress as well as to the resilience and vulnerability to such stress.
For each neurochemical, the review describes the acute effects, the brain regions of activity, the key functional interactions, and the association with resilience and psychopathology. For each neural mechanism, the review describes the neurochemicals and the brain regions involved, and the association with resilience and psychopathology.
Results
Eleven neurochemicals are identified and related to resilience and vulnerability to stress:
- cortisol
- dehydroepiandrosterone
- corticotropin-releasing hormone
- norepinephrine
- neuropeptide Y
- galanin)
- dopamine
- serotonin
- benzodiazepine receptors
- testosterone
- estrogen
The psychobiological mechanisms underlying three functions are presented as having particular importance for the character traits that relate to resilience and vulnerability to stress: (1) the regulation of reward and motivation (hedonia, optimism, and learned helplessness), (2) the response to anxiety and fear (fear conditioning, reconsolidation, and extinction), and (3) the development of adaptive social behavior (altruism, bonding, and teamwork).
Discussion
Although the acute response to stress has, first of all, protective values, most of the research on extreme stress has focused on the negative effects of stress on the brain and the body.
The acute response to stress will, however, have adverse consequences if it persists, is excessive or abnormal in some other ways. Whether or not there will be negative effects depends, to a large extent, upon the resilience and the vulnerability of the individual, both of which depend, in turn, on a complex interplay of numerous neurochemichals underlying multiple psychobiological mechanisms.
The review has a number of limitations, concerning in particular the fact that it is restricted to a limited number of mediators of the stress response. For example, glutamate, neurotrophic factors, substance P, and cholécystokinine, are not discussed in the review.
In spite of these limitations, this is a highly interesting review on the psychobiology of resilience and vulnerability. In particular, the review contributes to a better understanding of why some people are highly resilient to extreme stress, i.e. are able to cope with only minimal psychopathological consequences, while others are highly vulnerable to stress and react with major, and often persistent symptomatology.
In addition, some of the findings suggest that there may be ways to enhance the resilience or to lower the vulnerability of people to extreme stress, for example by using drugs or psychosocial treatments to increase, decrease, or regulate the activity of specific mediators that influence the response to stress.
By increasing the resilience of people to stress it may in fact become possible not only to treat stress-related psychopathology but also to prevent such psychopathology to occur in the first place.