Trait Anxiety and Fear Responses to Safety Cues: Stimulus Generalization or Sensitization?

Abnormal fear responding to threat cues may contribute to the aetiology and maintenance of persistent fears and pathological anxiety. Chronic anxiety may also involve abnormal fear responding to ??safety?? cues, which do not signal danger. Yet investigations of fear responding to acquired safety cues are scarce and the basis of such responding remains unclear. Moreover, previous studies do not distinguish between stimulus generalization (an associative mechanism based on perceptual similarity between threat and safety cues) and sensitization (a non-associative mechanism whereby fear responses to any novel, intense, or fear-related stimulus are temporarily elevated). This study investigated responses to acquired safety cues in volunteers with varying trait anxiety, using a novel fear conditioning paradigm designed to distinguish between effects of trait anxiety on generalization and sensitization. The paradigm used three conditioned stimuli: a threat cue (CS+) and two safety cues (CS?), one perceptually similar to the CS+ and one perceptually dissimilar. Conditioned fear to these cues was indexed by fear potentiation of the startle blink reflex, skin conductance responses, and self-report. To examine how trait anxiety moderated responses to safety cues, participants were divided into high and low trait anxiety subgroups. Startle, skin conductance, and self-reported fear measures indicated that generalization of fear occurred for the safety cue which resembled the threat cue, but not for the perceptually dissimilar safety cue, consistent with the stimulus generalization hypothesis. There was some evidence that stimulus generalization was exaggerated in anxious individuals. The current study sheds light on the mechanism by which fear responses to safety cues arise in healthy individuals, and offers some insight into the influence of this mechanism in chronic anxiety.     

Customary Trade and the Complications of Consent

Global justice theorists have given much attention to corporations' purchases of state‐owned natural resources controlled by dictators. These resources, the common argument goes, belong to the people rather than to those who exercise effective political power. Dictators who rely on violence to secure their political power and who sell state‐owned natural resources without authorisation from their people, or from their people's elected delegates, are therefore violating their peoples' property rights. But many dictatorships also distribute natural resource revenue to the population, and stopping to purchase natural resources from them is therefore likely to produce relative deprivation for the people, even while increasing the chances of the people gaining control over their property. Given these circumstances, can corporations buying the people's natural resources from a distributive dictatorship appeal to the people's consent as justification for such purchases? I consider this question by inspecting three types of consent to which resource corporations might appeal. I show that, under the circumstances of natural resource trade with distributive dictatorships, none of these types of consent can obtain. Hence, resource corporations cannot appeal to popular consent to defend their transactions with distributive dictatorships.