The effect of induced anxiety on cognition: threat of shock enhances aversive processing in healthy individuals

Individuals with anxiety disorders demonstrate altered cognitive performance including (1) cognitive biases towards negative stimuli (affective biases) and (2) increased cognitive rigidity (e.g., impaired conflict adaptation) on affective Stroop tasks. Threat of electric shock is frequently used to induce anxiety in healthy individuals, but the extent to which this manipulation mimics the cognitive impairment seen in anxiety disorders is unclear. In this study, 31 healthy individuals completed an affective Stroop task under safe and threat-of-shock conditions. We showed that threat (1) enhanced aversive processing and abolished a positive affective bias but (2) had no effect on conflict adaptation. Threat of shock thus partially models the effects of anxiety disorders on affective Stroop tasks. We suggest that the affective state of anxiety—which is common to both threat and anxiety disorders—modulates the neural inhibition of subcortical aversive processing, whilst pathologies unique to anxiety disorders modulate conflict adaptation.     

Skeptical Conclusions

For a putative knower S and a proposition P, two types of skepticism can be distinguished, depending on the conclusions they draw: outer skepticism, which concludes that S does not know that P, and inner skepticism, which concludes that S does not know whether P. This paper begins by showing that outer skepticism has undesirable consequences because that S does not know that P presupposes P, and inner skepticism does not have this undesirable consequence since that S does not know whether P does not presuppose P. We indicate that the two types of skepticism aim to different loci of doubts: while outer skepticism doubts whether we can gain an epistemic warrant for the actuality, inner skepticism doubts whether we can gain epistemic identification of the actuality. It is further indicated that responses to skepticism from externalist theories, as well as from fallibilist internalist theories, can only respond to outer skepticism but not to inner skepticism.     

Phases of Organ Integration and Conflict in a Transplant Recipient: A Longitudinal Study Using a Diary

In this paper the results from a research project on self-perception and psychological processing following transplantation of solid organs are presented. A diary at the individual case level was introduced to generate a longitudinal analysis. In the following paper we describe an evaluation of the entries of a single patient following a living donor kidney transplant. Conflicts in the relationship between the transplant recipient and the donor, who is also his wife, are clearly evident, and these are interpreted as incorporation conflicts in light of current psychoanalytic theory.     

The developmental psychometrics of big five self-reports: acquiescence, factor structure, coherence, and differentiation from ages 10 to 20

How do youths' personality reports differ from those of adults? To identify the year-by-year timing of developmental trends from late childhood (age 10) to early adulthood (age 20), the authors examined Big Five self-report data from a large and diverse Internet sample. At younger ages within this range, there were large individual differences in acquiescent responding, and acquiescence variability had pronounced effects on psychometric characteristics. Beyond the effects of acquiescence, self-reports generally became more coherent within domains, and better differentiated across domains, at older ages. Importantly, however, different Big Five domains showed different developmental trends. Extraversion showed especially pronounced age gains in coherence but no gains in differentiation. In contrast, Agreeableness and Conscientiousness showed large age gains in differentiation but only trivial gains in coherence. Neuroticism and Openness showed moderate gains in both coherence and differentiation. Comparisons of items that were relatively easy versus difficult to comprehend indicated that these patterns were not simply due to verbal comprehension. These findings have important implications for the study of personality characteristics and other psychological attributes in childhood and adolescence.     

Threat in dreams: an adaptation?

Revonsuo's influential Threat Simulation Theory (TST) predicts that people exposed to survival threats will have more threat dreams, and evince enhanced responses to dream threats, compared to those living in relatively safe conditions. Participants in a high crime area (South Africa: n=208) differed significantly from participants in a low crime area (Wales, UK: n=116) in having greater recent exposure to a life-threatening event (chi([1,N=186])(2)=14.84, p<.00012). Contrary to TST's predictions, the SA participants reported significantly fewer threat dreams (chi([1,N=287])(2)=6.11, p<.0134), and did not differ from the Welsh participants in responses to dream threats (Fisher's Exact test, p=.2478). Overall, the incidence of threat in dreams was extremely low-less than 20% of dreams featured realistic survival threats. Escape from dream threats occurred in less than 2% of dreams. We conclude that this evidence contradicts key aspects of TST.     

Shooting the messenger won’t change the news

Malcolm-Smith, Solms, Turnbull and Tredoux [Malcolm-Smith, S., Solms, M., Turnbull, O., & Tredoux, C. (2008). Threat in dreams: An adaptation? Consciousness and Cognition, 17, 1281–1291.] conducted a rigorous study that sampled two populations differentially exposed to threat in real life, and found that critical predictions from the Threat Simulation Theory of dreams [Revonsuo, A. (2000a). The reinterpretation of dreams: An evolutionary hypothesis of the function of dreaming. Behavioral and Brain Sciences, 23, 877-901.; Revonsuo, A. (2000b). Did ancestral humans dream for their lives? Behavioral and Brain Sciences, 23, 1063–1082.] were not supported. Specifically, we found no evidence of increased realistic threats to physical survival or enhanced threat avoidance in the dreams of those from the exposed population. Revonsuo and Valli’s [Revonsuo, A., & Valli, K. (2008). How to test the threat simulation theory. Consciousness and Cognition, 17, 1292-1296.] commentary on our study argues that the methods we used are so flawed as to render the results meaningless. In this response article, we address the criticisms raised in their commentary.     

Challenges To Human Equality

According to liberal egalitarian morality, all human beings are one another's moral equals. Nonhuman animals, by contrast, are not considered to be our moral equals. This essay considers two challenges to the liberal egalitarian view. One is the ``separation problem,' which is the challenge to identify a morally significant intrinsic difference between all human beings and all nonhuman animals. The other is the “equality problem,” which is to explain how all human beings can be morally equal when there are some human beings whose psychological capacities (and, in some cases, their psychological potentials as well) are no higher than those of certain nonhuman animals. The focus throughout is on the ethics of killing but the arguments are of broader relevance. The essay reaches a skeptical conclusion about our ability to meet these challenges.