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ABSTRACT: Though conditioned fear has long been acknowledged as an important etiologic mechanism in social anxiety disorder, past psychophysiological experiments have found no differences in general conditionability among social anxiety patients using generally aversive but socially nonspecific unconditioned stimuli (e.g., unpleasant odors and painful pressure). The authors applied a novel fear conditioning paradigm consisting of socially relevant unconditioned stimuli of critical facial expressions and verbal feedback. This study represents the first effort to assess the conditioning correlates of social anxiety disorder within an ecologically enhanced paradigm.
Subjects with social anxiety disorder and age- and gender-matched healthy comparison subjects underwent differential classical conditioning. Conditioned stimuli included images of three neutral facial expressions, each of which was paired with one of three audiovisual unconditioned stimuli: negative insults with critical faces (US(neg)), positive compliments with happy faces (US(pos)), or neutral comments with neutral faces (US(neu)). The conditioned response was measured as the fear-potentiation of the startle-blink reflex elicited during presentation of the conditioned stimuli.
Only social anxiety subjects demonstrated fear conditioning in response to facial expressions, as the startle-blink reflex was potentiated by the CS(neg) versus both CS(neu) and CS(pos) among those with the disorder, while healthy comparison subjects displayed no evidence of conditioned startle-potentiation. Such group differences in conditioning were independent of levels of anxiety to the unconditioned stimulus, implicating associative processes rather than increased unconditioned stimulus reactivity as the active mechanism underlying enhanced conditioned startle-potentiation among social anxiety subjects.
Results support a conditioning contribution to social anxiety disorder and underscore the importance of disorder-relevant unconditioned stimuli when studying the conditioning correlates of pathologic anxiety.
American Journal of Psychiatry 02/2008; 165(1):124-32. · 12.54 Impact Factor
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ABSTRACT: Contextual fear conditioning was examined using the startle reflex in two groups of participants over two sessions separated by 1/2 h. The conditioned stimulus (CS) was paired (paired group) or not (unpaired group) with an unpleasant shock during conditioning. The paired group showed conditioning to the CS that was well retained over the retention interval. Session 1 intertrial interval startles—a measure of contextual conditioning—were greater in the unpaired compared to the paired group. Context conditioning was retained in Session 2 and was present before the shock electrodes were attached. Self-rating of state anxiety, arousal, and pleasure indicated differential changes in mood from Session 1 to Session 2 in the two groups, with the unpaired group showing relatively greater negative affects compared to the paired group. These results indicate that unpredictable shocks lead to greater context conditioning as measured by startle and self-reports.
Psychophysiology 04/2001; 38(3):383 - 390. · 3.29 Impact Factor
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ABSTRACT: The present study examined the impact of safety signals on contextual fear and the possibility of using an intense jet of air (airblast) directed to the larynx to induce an aversive emotional state. Three groups (
N = 12 per group) participated in the study. In one group, the startle probe was an intense white noise and the aversive stimulus was an unpleasant shock. In another group, the startle probe was also an intense white noise but the aversive stimulus was an airblast to the larynx. In the third group, the startle probe was a brief airpuff to the forehead and the aversive stimulus was a loud noise. Ss anticipated the aversive stimulus during threat, but not during safe conditions signaled by different colored lights. Results are consistent with animal learning theories that suggest that fear is reduced by signals predicting the absence of aversive events, compared to signals predicting their presence or signal-free periods. Also, results suggest that airblasts could be substituted for electric shocks or loud sounds in a fear-potentiated startle experiment, especially when working with certain populations such as children or psychiatric patients. (PsycINFO Database Record (c) 2012 APA, all rights reserved)
Journal of Psychophysiology 10/1998; · 1.54 Impact Factor
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ABSTRACT: The time course of the facilitation of the acoustic startle reflex induced by anticipation of electric shocks was measured in 20 normal volunteers. Shocks could be administered during the last 10 s of 45-s threat conditions but not during 50-s no-threat conditions, each condition being signaled by a different light. Consistent with previous data, overall eyeblink startle levels were higher during the threat than during the no-threat conditions. However, the magnitude of this fear-potentiated startle effect became progressively larger in the threat condition the longer the light was on and then abruptly decreased with the onset of the light signaling the no-threat condition. These effects of the threat of shock on startle were interpreted in terms of anticipatory anxiety. Other interpretations, such as changes in selective or generalized attention, were also discussed. This paradigm provides a method to assess the time course of anticipatory anxiety in humans.
Psychophysiology 06/1993; 30(4):340 - 346. · 3.29 Impact Factor
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ABSTRACT: High-functioning autistic individuals were compared with age-matched normal control subjects on a visual recognition memory task. In order to evaluate the effects of meaning anddelay on the visual memory of autistic individuals, meaningful (pictures) and meaningless (nonsense shapes) stimuli were presented visually in no delay and 1-minute delay intervals to both groups. It was concluded that autistic subjects perform particularly poorly on meaningless materials, but they are able to utilize meaning to aid their visual memory. Contrary to expectations, 1-minute delay intervals did not differentially affect the visual memory performance of autistic individuals compared to control subjects. The results do not support the idea of a simple parallel between autism and mediotemporal lobe amnesias. The visual memory performance of the autistic subjects was discussed in the light of the possibility of a subtle involvement of the mediotemporal brain structures and inflexible cognitive strategies poorly suited to encode novel information.
Journal of Autism and Developmental Disorders 11/1988; 18(4):601-615. · 3.34 Impact Factor
