clude muscular tension, which among other things can lead to
trembling, twitching stiff and jerky motion, defective speech and
a change in stance.
Mann (1992) prepared a research overview on the relationship
between stress, emotional states and risk taking. Among other
things, the conclusions were described that maintain that stress
which is created by crises produces a reduced time perspective,
socalled cognitive rigidity, i.e. that the individual becomes con-
servative in his or her thoughts. This subsequently leads to:
- Immediate objectives or objectives within a brief period of
time being more highly valued. - Conclusions being drawn prematurely.
- Limited searching for alternatives.
- Less careful evaluation of alternatives and their consequences.
The reader surely perceives the substantial significance this can
have on the decisions that are made, and consequently on the
results of an emergency response operation. A certain amount
of stress is often necessary in encouraging the search for infor-
mation and the evaluation of alternative actions. In the event
of heightened stress, however, this process becomes less rich in
content and the quality of the ensuing decision thus suffers. Ex-
treme pressure against the clock has a direct negative effect on
the decisions that are made. Mann (1992) suggests an experiment
in which decisions that involve substantial losses are to be made
under extreme pressure against the clock. He anticipates that the
results of such experiments would demonstrate that an anxious
or troubled decision maker would be more likely to exercise less
caution than more.
One of Mann’s (1992) primary conclusions is otherwise that
mildly positive emotional states result in the individual avoiding
risks and exercising caution under conditions with substantial
probability for significant losses. Positive emotional states can en-
tail careless decisions, but can also entail that the decision maker
does not involve himself sufficiently in a problem and makes it
more complex than necessary.
Orasanu (1997) prepared an overview of the effects of stress,
and summarises a number of research efforts in four points:
- Individuals subjected to stress make more mistakes in a variety
of different types of tasks than individuals who are not subjec
ted to stress.