248 ASSESSMENT AND INTERVENTION STRATEGIES
achieved with imaginal exposure, although most behavior therapists recommend the
use of in vivo exposure whenever possible because it appears to yield more potent and
generalizable treatment effects (e.g., Antony & Swinson, 2000a; Foa & Kozak, 1985;
Steketee, 1993). Foa and McNally (1996) stated that imaginal scripts can not be as
effective as real-life exposure, because they provide improvished informational input
and so are less evocative of the fear memory structure. However, there are times when
imaginal exposure is the preferred modality because in vivo exposure is impractical (or
impossible), or the addition of imaginal exercises enhances treatment maintenance of
externally based exposure (Kozak & Foa, 1997). The following is a list of occasions
when imaginal exposure might be the more appropriate therapeutic modality.
••When the object of fear is a thought, image, or idea, imaginal exposure may be
the only possible therapeutic approach (e.g., in OCD thinking of the end of the
world, of eternal damnation, of committing the “unpardonable sin”).
••Imaginal exposure is used when it is impractical or unethical to utilize in vivo
exposure (e.g., fear of shouting obscenities in church, thoughts of accidentally
causing harm or injury to another, fear of natural disasters).
••In PTSD imaginal exposure is often utilized when fear is associated with memory
of a trauma that happened in a distant geographic location or at an earlier time
of life (Keane & Barlow, 2002).
••Borkovec (1994) has argued that worry is a conceptually based cognitive strat-
egy used to avoid aversive imagery and the physiological arousal associated with
threatening topics. Imaginal exposure has become an important component of
CBT protocols for GAD (Brown, O’Leary, & Barlow, 2001; Rygh & Sanderson,
2004).
••Imaginal exposure is effective as a preparatory skills exercise such as in treating
public speaking anxiety where imagery and role-play rehearsal are utilized for
skills acquisition prior to in vivo exposure.
••Finally, imaginal exposure may be employed initially when a client refuses to
engage in real-life exposure in order to facilitate the eventual acceptance of in
vivo exposure exercises (Antony & Swinson, 2000a).Implementation
The general guidelines previously discussed under situational exposure are applicable to
imaginal exposure, although the following caveat should be taken into account. First,
flooding or abrupt exposure procedures, which involve the immediate presentation of
the most feared scenario, are used more often in imaginal than in in vivo exposure. This
is particularly true for the imagery exposure used in PTSD or GAD where a hierarchi-
cal approach to trauma or “worst-case scenario” may not be necessary. Since flooding
is more efficient and equally (or more) effective to hierarchical exposure (Foa & Kozak,
1985; White & Barlow, 2002), clinicians should consider whether an intensive form of
imaginal exposure can be applied.
Second, imaginal exposure sessions are usually no more than 30 minutes and so
are much shorter in duration than situational exposure. Sustained imagery exercises
require a great deal of attentional resources so most individuals would not be able to
maintain their full concentration on the imagery task for prolonged periods. However,