David Torrents-Rodas

No effect of trait anxiety on differential fear conditioning or fear generalization.

Previous studies have shown that individuals with anxiety disorders exhibit deficits in fear inhibition and excessive generalization of fear, but little data exist on individuals at risk from these disorders. The present study examined the role of trait anxiety in the acquisition and generalization of fear in 126 healthy participants selected on the basis of their trait-anxiety scores. Measures of conditioning included fear-potentiated startle, skin conductance response and online risk ratings for the unconditioned stimulus. Contrary to our hypotheses, trait anxiety did not have any effect either on the acquisition or the generalization of fear. Our results suggest that these fear conditioning processes are not impaired in individuals at risk from anxiety.

Conditioned fear acquisition and generalization in generalized anxiety disorder

Abnormal fear conditioning processes (including fear acquisition and conditioned fear-generalization) have been implicated in the pathogenesis of anxiety disorders. Previous research has shown that individuals with panic disorder present enhanced conditioned fear-generalization in comparison to healthy controls. Enhanced conditioned fear-generalization could also characterize generalized anxiety disorder (GAD), but research so far is inconclusive. An important confounding factor in previous research is comorbidity. The present study examined conditioned fear-acquisition and fear-generalization in 28 patients with GAD and 30 healthy controls using a recently developed fear acquisition and generalization paradigm assessing fear-potentiated startle and online expectancies of the unconditioned stimulus. Analyses focused on GAD patients without comorbidity but included also patients with comorbid anxiety disorders. Patients and controls did not differ as regards fear acquisition. However, contrary to our hypothesis, both groups did not differ either in most indexes of conditioned fear-generalization. Moreover, dimensional measures of GAD symptoms were not correlated with conditioned fear-generalization indexes. Comorbidity did not have a significant impact on the results. Our data suggest that conditioned fear-generalization is not enhanced in GAD. Results are discussed with special attention to the possible effects of comorbidity on fear learning abnormalities.

Acquisition and generalization of fear conditioning are not modulated by the BDNF-val66met polymorphism in humans.

Few studies have investigated the role of the BDNF-val66met polymorphism in fear conditioning in humans, and previous results have been inconsistent. In the present study, we examined whether the BDNF-val66met was associated with differences in the acquisition and generalization of fear during a differential conditioning paradigm in a large sample of participants (N = 141). Using three different indexes of fear learning (fear-potentiated startle, skin conductance response, and online risk ratings) no effects of the BDNF-val66met were found either on the acquisition or the generalization of conditioned fear. Taken together with previous data, our study suggests that the BDNF-val66met polymorphism has no effect on the acquisition or generalization of fear.

Testing the temporal stability of individual differences in the acquisition and generalization of fear.

We studied the temporal stability of individual differences in the acquisition and generalization of fear. Seventy-one participants were tested in two almost identical fear-acquisition and fear-generalization sessions (separated by 8 months). Acquisition and generalization were measured by the fear-potentiated startle, the skin conductance response, and online expectancies of the unconditioned stimulus. To control for the effects of previous experience, different stimuli were used for half of the participants in Session 2. Acquisition and generalization did not differ across sessions or as a function of the stimuli used in Session 2, and a significant proportion of individual differences in these processes was stable over time (generalizability coefficients ranged from 0.17 to 0.38). When the same stimuli were used, acquisition measures showed compromised stability. The results are discussed in terms of their theoretical and applied implications.

Does fear extinction in the laboratory predict outcomes of exposure therapy? A treatment analog study

Fear extinction models have a key role in our understanding of anxiety disorders and their treatment with exposure therapy. Here, we tested whether individual differences in fear extinction learning and fear extinction recall in the laboratory were associated with the outcomes of an exposure therapy analog (ETA). Fifty adults with fear of spiders participated in a two-day fear-learning paradigm assessing fear extinction learning and fear extinction recall, and then underwent a brief ETA. Correlational analyses indicated that enhanced extinction learning was associated with better ETA outcome. Our results partially support the idea that individual differences in fear extinction learning may be associated with exposure therapy outcome, but suggest that further research in this area is needed.

Impact when receiving a diagnosis: Additive and multiplicative effects between illness severity and perception of control

Based on Lazarus’ transactional model of stress, this study examined how the information provided in a medical diagnosis (the severity of the illness, the effectiveness of the treatment and the self-efficacy to follow this treatment) are combined to generate perception of stress. Twenty-seven scenarios were presented to 152 volunteer students and their level of perceived stress was recorded. Results revealed that the lack of efficacy of the treatment raises the perception of stress proportionally to the different degrees of illness severity, but having a low perceived ability to follow the treatment triggers high levels of stress, particularly when the diagnosis is serious.

Conditioned Subjective Responses to Socially Relevant Stimuli in Social Anxiety Disorder and Subclinical Social Anxiety

UNLABELLED Although enhanced fear conditioning has been implicated in the origins of social anxiety disorder (SAD), laboratory evidence in support of this association is limited. Using a paradigm employing socially relevant unconditioned stimuli, we conducted two separate studies to asses fear conditioning in individuals with SAD and non-clinical individuals with high social anxiety (subclinical social anxiety [SSA]). They were compared with age-matched and gender-matched individuals with another anxiety disorder (panic disorder with agoraphobia) and healthy controls (Study 1) and with individuals with low social anxiety (Study 2). Contrary to our expectations, in both studies, self-report measures (ratings of anxiety, unpleasantness and arousal to the conditioned stimuli) of fear conditioning failed to discriminate between SAD or SSA and the other participant groups. Our results suggest that enhanced fear conditioning does not play a major role in pathological social anxiety. KEY PRACTITIONER MESSAGE We used a social conditioning paradigm to study fear conditioning in clinical and subclinical social anxiety. We found no evidence of enhanced fear conditioning in social anxiety individuals. Enhanced fear conditioning may not be a hallmark of pathological social anxiety.

Attentional Control and Fear Extinction in Subclinical Fear: An Exploratory Study

Attentional control (AC) and fear extinction learning are known to be involved in pathological anxiety. In this study we explored whether individual differences in non-emotional AC were associated with individual differences in the magnitude and gradient of fear extinction (learning and recall). In 50 individuals with fear of spiders, we collected measures of non-emotional AC by means of self-report and by assessing the functioning of the major attention networks (executive control, orienting, and alerting). The participants then underwent a paradigm assessing fear extinction learning and extinction recall. The two components of the orienting network functioning (costs and benefits) were significantly associated with fear extinction gradient over and above the effects of trait anxiety. Specifically, participants with enhanced orienting costs (i.e., difficulties in disengaging attention from cues not relevant for the task) showed faster extinction learning, while those with enhanced orienting benefits (i.e., attention facilitated by valid cues) exhibited faster extinction recall as measured by fear-potentiated startle and Unconditioned Stimulus expectancies, respectively. Our findings suggest that, in non-emotional conditions, the orienting component of attention may be predictive of fear extinction. They also show that the use of fear extinction gradients and the exploration of individual differences in non-emotional AC (using performance-based measures of attentional network functioning) can provide a better understanding of individual differences in fear learning. Our findings also may help to understand differences in exposure therapy outcomes.