Panic Disorder 301
report studies have supported the catastrophic misinterpretation hypothesis of bodily
sensations, although most found that the interpretation bias is not specific to internal
sensations alone and that anxiety interpretations (i.e., an expectation of becoming more
anxious) are much more common than truly harm- related catastrophes (i.e., appraisals
of dying from suffocation or a heart attack).
A few studies have investigated the presence of catastrophic misinterpretations in
panic disorder samples that have been exposed to fear situations. Occurrence of a panic
attack leads to greater expectation of subsequent fear or a heightening of anticipatory
anxiety, which increases the likelihood that individuals will consider their anxious
symptoms highly threatening (i.e., Rachman & Levitt, 1985). Moreover, when panic
occurs during exposure to a fear situation, panic disorder individuals experience more
bodily sensations and catastrophic cognitions than during the nonpanic exposure trials,
although 27% (n = 8/30) of the panic episodes were not associated with any fearful cog-
nitions (Rachman, Lopatka, & Levitt, 1988). In a further analysis of these data, Rach-
man, Levitt, and Lopatka (1987) found that individuals with panic disorder were four
times more likely to have a panic attack when the bodily sensation was accompanied
by catastrophic cognitions. Street et al. (1989) also found a high rate of catastrophic
thinking when individuals recorded their next three panic attacks, especially when the
attacks were expected. In addition there were many moderate correlations between the
expected disturbing cognitions and their corresponding physical sensations (see Rach-
man et al., 1987, for similar finding).
Kenardy and Taylor (1999) had 10 women with panic disorder use a computer diary
to self- monitor onset of panic attacks over a 7-day period. Analysis revealed that indi-
viduals overpredicted panic attacks; in 70% of cases the expectation of an attack never
materialized. Moreover, catastrophic cognitions and somatic symptoms were common
before expected but not unexpected panic attacks, indicating that catastrophic thoughts
were associated with prediction or expectation of a panic attack rather than its actual
occurrence. Finally, a small pilot study of panic disorder found that 3.25 hours of belief
disconfirmation exposure resulted in significantly greater improvement in frequency
and belief of agoraphobic cognitions as well as symptom measures than the group who
received habituation exposure training only (Salkovskis, Hackmann, Wells, Gelder, &
Clark, 2006). This suggests that reductions in catastrophic interpretations lead to an
improvement in anxious and panic symptoms. Overall, these studies support the cata-
strophic misinterpretation hypothesis with two caveats. First, Rachman et al. (1987) did
find a small number of “noncognitive panic attacks” that are difficult to explain from
the catastrophic misinterpretation perspective. And second, some of the expected com-
binations of bodily sensations and catastrophic cognitions were not found such as heart
palpitations, fear of heart attack, and various combinations of symptoms could lead to
the same catastrophic cognition.
The strongest evidence for the catastrophic misinterpretation hypothesis comes
from experiments involving panic induction via biological challenge (e.g., lactate fusion,
CO 2 enriched air, hyperventilation, or exercise). There is considerable evidence that
some form of cognitive mediation is a critical factor that influences the frequency of
panic induction and heightened anxiety produced by these biological challenge experi-
ments (D. M. Clark, 1993). In order to separate the effects of the induction and indi-
viduals’ cognitions, participants typically are randomly assigned to receive instructions
to expect that the induction would lead to unpleasant reactions or that the induction