There has been the clinical impression that people with higher levels
of anxiety and central arousal are more prone to develop cocaine-induc
ed paranoia (CIP), but this notion has not been formally studied. In t
he current study, we examined the differences between 28 CIP-endorsing
and 16 CIP-denying chronic cocaine users in their levels of stare and
trait anxiety as measured by the Spielberger State-Tait Anxiety Inven
tory. We also studied levels of central arousal and reactivity using p
upil size measures both during exposure to neutral, abstract, non-drug
cues, and after exposure to a cocaine cue. Levels of trait (but not s
tate) anxiety were significantly higher in the CIP group than in the n
on-CIP group. Moreover, while there were no significant pupil size dif
ferences or changes between the two groups while viewing neutral, abst
ract video images, the CIP group had significantly greater pupillary d
ilation in response to a video image of crack cocaine than did the non
-CIP group. These significant differences remained even after covaryin
g for anxiety scores. The study findings seem relevant to studies of a
utonomic reactivity in response to drug cues in cocaine-dependent pati
ents; such studies might remain attentive to potential cue reactivity
differences between patients endorsing and those denying CIP. Finally,
this is the first study showing higher trait anxiety in patients with
CIP.