Depression and Stress: A Biopsychosocial Exploration of Evolved Functions and Mechanisms

Abstract

Depression is a common and debilitating disorder linked to social adversity and stress. There have been many theories suggesting possible evolved functions of depression but few have explored evolved defensive mechanisms for coping with stressful events and how these maybe compromised in human depression. This paper will review some of the current evolutionary theories of depression and explore how major depression can arise when evolved defences to cope with adversity (e.g., fight, flight, disengage, submit and help-seeking) are aroused but blocked, arrested or ineffective. Psychosocial stressors can be seen as both activating,but also as arresting, evolved stress-coping defences leading to chronic states of stress with physiological effects on mood. This paper is set in the context of an evolution informed biopsychosocial approach.

Entrapment and Defeat Perceptions in Depressive Symptomatology: Through an Evolutionary Approach

“…Dixon and colleagues (Dixon, Fisch, Huber, & Walser, 1989;Dixon, 1998) and Gilbert (1992Gilbert ( , 2001 argue that when confronted with a social stressor, animals will either seek support, submit (appease), take flight, or attack. However, if these defensive behaviors are activated but blocked or are ineffective, they can remain in a high state of arousal without resolution, and this has a downward impact on mood.…”

Depression, Perceived Inferiority, and Interpersonal Behavior: Evidence for the Involuntary Defeat Strategy

“…According to Gilbert (1992aGilbert ( , 1992bGilbert ( , 2000Gilbert ( , 2001aGilbert ( , 2001b, humans have an evolved set of defensive strategies that can be activated to varying degrees when they find themselves facing defeat. These defenses include "fight" (renewed efforts to win the contest or achieve the goal), "flight" (escaping from or avoiding the situation), help-seeking, and disengagement (relinquishing the goal and/or accepting one's lowered rank).…”

The assessment of psychological symptoms of patients referred to community mental health teams: distress, chronicity and life interference

“…Indeed, it is possible that some people become more depressed and anxious as the physiological mediators of stress impact on sleep and fatigue (Gilbert, 2001). Given the high rates of these symptoms and their distress, CMHTs may needs skills to intervene in these specific problems.…”

“…Nearly 55% felt they held their 'anger in'. Such behaviour (especially if it is ruminative anger and resentment) may have serious effects on stress systems (Gilbert, 2001) and social relationships, which may require a more focused approach (Leff et al, 2000). Symptoms of drug use and alcohol were relatively low but of sufficient frequency to indicate a need for access to specialist services.…”

“…It is possible that these three symptoms are related to non-specific dysregulation of stress systems and cut across diagnostic boundaries (Gilbert, 2001). Not unexpectedly, nearly twothirds of this group endorsed feeling anhedonic.…”