Fear of threatening contexts often generalizes to similar, safe contexts but few studies have investigated how contextual information influences cue generalization. In this study we explored whether fear responses to cues would generalize more broadly in a threatening compared to a safe context. Forty-eight participants underwent a differential cue-in-context conditioning protocol followed by a generalization test while we recorded psychophysiological and subjective responses. Two faces appeared on a computer screen in two contexts. One face (CS+) in the threat context (CTX+) was followed by a female scream 80% of the time, while another face (CS-) was not reinforced. No faces were reinforced in the safe context (CTX-). In the generalization test, the CSs and four morphs varying in similarity with the CS+ were presented in both contexts. During acquisition, conditioned responses to the cues was registered for all measures and the differential responding between CS+ and CS- was higher in CTX+ for US-expectancy ratings and skin conductance responses but the affective ratings and ssVEPs were not context-sensitive. During test, adaptive generalized responses were evident for all measures. Despite increased US-expectancy ratings in CTX+, participants exhibited similar cue generalization in both contexts, suggesting that threatening contexts do not influence cue generalization.

Fear overgeneralization and perceived uncertainty about future outcomes have been suggested as risk factors for clinical anxiety. However, little is known regarding how they influence each other. In this study, we investigated whether different levels of threat uncertainty influence fear generalization. Three groups of healthy participants underwent a differential fear conditioning protocol followed by a generalization test. All groups learned to associate one female face (conditioned stimulus, CS+) with a female scream (unconditioned stimulus, US), whereas the other face (CS-) was not associated with the scream. In order to manipulate threat uncertainty, one group (low uncertainty, n = 26) received 80%, the second group (moderate uncertainty, n = 32) received 60%, and the third group (high uncertainty, n = 30) 40% CS-US contingency. In the generalization test, all groups saw CS+ and CS- again along with four morphs resembling the CSs in steps of 20%. Subjective (expectancy, valence, and arousal ratings), psychophysiological (skin conductance response, SCR), and visuocortical (steady-state visual evoked potentials, ssVEPs) indices of fear were registered. Participants expected the US according to their reinforcement schedules and the discriminative responses to CS+/CS- increased with more uncertainty in skin conductance. However, acquisition of conditioned fear was not evident in ssVEPs. During the generalization test, we found no effect of threat uncertainty in any of the measured variables, but the strength of generalization for threat expectancy ratings was positively correlated with dispositional intolerance of uncertainty. This study suggests that mere threat uncertainty does not modulate fear generalization.

Avoidance is typically adaptive given it prevents threat. However, avoidance becomes maladaptive when it is executed out of proportion of threat (i.e., excessive or insufficient avoidance), persists in the absence of threat, or excessively generalizes to other innocuous situations. Although there has been an increase in research in these different processes of maladaptive avoidance, the role of inter-individual differences in these avoidance processes receives less research attention, despite its theoretical and clinical importance. In this systematic review, we summarized the role of inter-individual traits that relate to risk or resilient factors for anxiety-related disorders, trauma-and stressor-related disorders, obsessive-compulsive related disorders, pain related disorders, eating-related disorders, and affective disorders. A majority of the inter-individual differences had an apparent mixed or null effect on the different processes of avoidance. We discussed this lack of evidence of inter-individual differences on avoidance due to a lack of methodological and/or analytical consensus in the field, in addition to a lack of integration of recent findings into existing theories. Recommendations for future research are discussed, with a focus on examining the conditions or experimental parameters for certain inter-individual traits to manifest their effects on avoidance, identifying the nuances of methodological and/or inter-individual differences in avoidance, and a call for integrating recent preliminary findings into existing theories.