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120 Biobehavioral Resilience to Stress

first used a startle blink reflex* paradigm to demonstrate the effect of antici-

pation on emotional responses to an aversive stimulus. Specifi cally, Grillon
et al. (1993) demonstrated that the magnitude of the startle blink refl ex is
greater when subjects anticipate a negative event (shock) than when they
anticipate a neutral event (no shocks). Nitschke et al. (2002) replicated this

finding using negative pictures as an aversive stimuli and observed in addi-
tion that state anxiety did not moderate the effect. However, in a separate

neuroimaging study, participants who anticipated aversive shock also dem-
onstrated increased brain activation in the left insula, where activation is

associated with emotional response to aversive stimulation and was found to
correlate with state anxiety (Chua, Krams, Toni, Passingham & Dolan, 1999).
Although it remains unclear what role state anxiety may play in anticipatory

emotion, these findings clearly support the contention that anticipation plays

a key role in influencing emotional response prior to expected stress and
further that the anticipatory emotional response may be predictive of subse-
quent emotional response to the anticipated stressor itself.
The results of a recent neuroimaging study (Nitschke, Sarinopoulos,

Mackiewicz, Schaefer & Davidson, 2006) are consistent with earlier obser-
vations and provide additional support for the argument that anticipation
generates predictive emotional responses. In this study, participants were
given warning cues that signaled upcoming picture stimuli as either aver-
sive or neutral. Participants’ brain activity was recorded during anticipa-
tion and viewing of the picture stimuli. Interestingly, several areas of the
brain previously shown to be associated with emotion (anterior cingulate,
dorsolateral prefrontal cortex, orbitofrontal cortex) were activated during
anticipation as well as during actual viewing of the aversive or neutral pic-
ture stimuli. There was greater activation across these regions for aversive

than for neutral stimuli. Th ese fi ndings suggest that anticipation of a nega-
tive event may generate a preemptory emotional response, which mimics
subsequent emotional response to the event itself (Nitschke, Sarinopoulos,
Mackiewicz, Schaefer & Davidson, 2006). The investigators also reported a

correlation between self-reported state and trait negative aff ect as measured
by the positive and negative affectivity schedule (PANAS; Watson, Clark &

Tellegen, 1988) and increased activation in the right dorsolateral prefrontal
cortex during anticipation (Nitschke et al., 2006). Th is fi nding is consistent
with the previous research, indicating that people who are high in negative

affect also exhibit greater right-to-left hemisphere asymmetrical brain activ-

ity (Davidson, 1992).

* The startle blink response is measured by the magnitude of constriction of muscles
around the eye in response to a startling stimulus (usually a loud noise or puff of air in

the eye). The startle blink reflex tends to be greater in magnitude when people are view-
ing negative (versus neutral or positive) pictures (Lang, Bradley & Cuthbert, 1990).

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