Anxiety Sensitivity

Anxiety sensitivity describes the tendency for individuals to fear sensations
they associate with anxiety because of beliefs that anxiety may result in
harmful consequences. Research in the development and assessment of this
construct was pioneered by Steven Reiss and his associates in the late 1980’s.
They developed a sixteen-item questionnaire, the Anxiety Sensitivity Index
(ASI), to measure anxiety sensitivity and found it to be both reliable and
valid. Anxiety sensitivity has been most closely related to panic disorder, an
anxiety disorder characterized by frequent, incapacitating episodes of extreme
fear or discomfort. In fact, as a group, individuals with panic disorder
score higher on the ASI than individuals with any other anxiety disorder.
Furthermore, some researchers have demonstrated that individuals scoring
high on the ASI are five times more likely to develop an anxiety disorder after
a three-year follow-up.

Research investigating responses to arithmetic, caffeine, and hyperventilation
challenges in the laboratory has demonstrated that individual differences
in anxiety sensitivity levels are probably more closely related to the
subjective experience of anxiousness than to actual physiological changes.
Individuals high and low on anxiety sensitivity, however, have exhibited differential
heart-rate reactivity to a mental arithmetic stressor. That is, individuals
high on anxiety sensitivity show a greater acceleration in heart rate than
individuals low on anxiety sensitivity when engaging in an arithmetic challenge.
Individuals scoring high on the ASI also more accurately perceive actual
changes in their physiology when compared with their low-scoring
counterparts. Such heightened reactivity and sensitivity to physiological
change may partially explain how anxiety sensitivity influences the development of anxiety disorders. Individuals high in anxiety sensitivity may be
more reactive to environmental threat; therefore, their increased sensitivity
may have a physiological basis. They also may be more likely to detect
changes in their physiology, which they are then more likely to attribute to
threat or danger.

On a more general note, cardiovascular and electrodermal measures can
differentiate between anxiety patients and other people at rest. The differences
become greater under conditions of stimulation. Delayed habituation
rates in anxiety patients are also part of the pattern of physiological overarousal
typically seen in individuals with heightened anxiety. Indeed, heightened
physiological arousal is one of the hallmark characteristics of anxiety.