Selective attention to real phobic and safety stimuli
Thorpe SJ., Salkovskis PM.
Many previous information processing studies have noted that people with severe anxiety selectively attend to threat stimuli. The experiment reported here tests the hypothesis that, when real threat stimuli are used instead of semantic stimuli, attention may be divided between threat and safety. Spider phobics and controls participated in a reaction time experiment, in which the target stimulus (a light) was programmed to randomly occur either by the only door to the room or by the wall opposite that door. They were asked to press a response button as soon as they detected the light coming on by the wall or by the door. Next, for half the participants, a live Zebra Tarantula was placed next to the stimulus light, either by the door (threat and safety/escape coincide) or by the wall (threat and safety/escape divided), and the experiment repeated. The rest of the participants repeated the baseline condition to control for practice effects. Response latencies to the light stimuli were analysed. Results suggest that spider phobics (but not controls) were faster to respond to the light when it occurred in the location where the threat and the escape stimuli coincided, (when the spider was by the door), than when it occurred in the location where the threat and the escape stimuli were divided (when the spider was by the wall). These results suggest that phobics may allocate attention not only to threat but also to safety. It is proposed that such effects may be less detectable, or absent, when the threat stimuli are semantic or symbolic because participants discriminate between threat and its symbolic representation.