Mw. Miller et Cj. Patrick, Trait differences in affective and attentional responding to threat revealed by emotional stroop interference and startle reflex modulation, BEHAV THER, 31(4), 2001, pp. 757-776
This study utilized startle reflex and reaction time (RT) measures to exami
ne the hypothesis that anxious individuals exhibit an attentional bias for
threatening information. High and low trait-anxious (HTA; LTA) participants
performed an emotional Stroop task in which pleasant, neutral, and threat
words were presented under conditions of anticipation, or no anticipation,
of electric shock. Acoustic startle probes were presented during the interv
al between word presentation and production of the color-naming response. H
TA participants showed longer color-naming RT for threat words than pleasan
t words under both shock anticipation and safe conditions of the procedure.
Under safe conditions, startle patterns paralleled these effects with HTA
participants exhibiting smaller blink responses - indicating greater alloca
tion of processing resources - for threat words than pleasant words. Under
shock anticipation conditions, HTA individuals showed an opposite response
pattern: startle blinks were potentiated for threat words relative to pleas
ant, indicating that the emotional impact of the threat words was enhanced
by the aversive mood state. Despite evidence that the startle response effe
cts were limited by habituation to the first half (ISO trials) of the proce
dure, these findings support the hypothesis that HTA individuals possess an
attentional bias for threatening information and exhibit greater defensive
emotional reactivity to threat cues during states of heightened negative a
ffectivity than low anxious individuals.