understanding of the causes and effects of psychosocial stress have been limited by
the difficulty in coming to an agreement on just what stress is. Hans Selye’s classic
definition of stress as“the non-specific response of the body to any demand made
on it”(Selye 1973 , p. 692) allows an understanding of the basic concepts implicit in
the scientific conception of general stress: non-specificity, reliance on responses as
opposed to stimuli for identification of the existence of stress, and generality of the
response to many stimuli.
Selye ( 1956 ) conceptualized general stress, which he referred to as the“general
adaptation syndrome,”as occurring in three phases: an initial“alarm reaction,”a
stage of resistance, andfinally a stage of exhaustion. The alarm reaction, focused on
by many in identifying stress, is often anticipatory, preparing the individual for the
coming stressful conditions. The stage of resistance occurs after one has identified
the stressor and made specific adaptive responses to deal with it. In many cases, the
physiological conditions in the stage of resistance are much different than responses
during the alarm reaction. Finally, if the stressful conditions persist, one may reach
the limits of resistance, with the loss of the adaptive responses. This stage of
exhaustion invokes a response much like the alarm reaction; if a new means of
adapting is not found, the organism’s survival is in peril.
The“alarm reaction” stage of the process that Selye outlined is sometimes
conceptualized as“acute stress,”with the later stages associated with chronic stress
exposure. Alternatively, frequent experience of the alarm reaction may constitute
chronic stress. The alarm reaction may be the only stage in a given circumstance.
For instance, Sapolsky ( 2004 ) has noted that many prey species such as zebras react
with a strenuous alarm reaction when confronted with a nearby predator. However,
if the zebra is not eaten in the encounter, it quickly goes back to its usual mode of
what could be described as watchfulness without anxiety.
Many theories about stress focus on the alarm reaction phase of the stress
process. This phase has been defined variously by the type of stimulus (stressor),
type of response, or the“intervening”variable that links stimuli with specific
responses. Psychological theories of stress often implicate cognitive processes
specific to individuals as the intervening variable in determining whether a given
circumstance is stressful or not. For instance, Lazarus’theory (Lazarus 1966 ) states
that general stress occurs only when two conditions are met: there is a cognitive
appraisal that a given situation is potentially harmful, and there is a second appraisal
that this situation cannot be coped with routinely. Lazarus ( 1993 , p. 15) has noted
that these appraisal processes are“often non-volitional and unconscious.”Thus, one
must separate the conscious experience of stress from the cognitive appraisal that
leads to a physiological stress response.
Lazarus’conception of stress is one example of a theory that defines psy-
chosocial stress as an intervening variable, and also shows the importance of
individual differences based on knowledge and experience for determining if a
given situation is stressful or not. Other theories have similar characteristics; for
example the cognitive activation theory of stress states that stress is triggered when
there is a cognitive appraisal of a discrepancy“between what should be and what
is”(Ursin and Eriksen 2004 , p. 567). The importance of individual knowledge and
118 D.E. Brown