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Introduction Placebo effects are physiological or psychological responses resulting from an individual's interpretations and expectations of a therapeutic intervention (Benedetti, 2009; Stewart-Williams & Podd, 2004). One area in which placebo [...], Placebo effects are important in pain reduction, but the effects are inconsistent. Prior experience with a pain stimulus may moderate placebo analgesia. The current study tests the effect of prior experience with a pain stimulus on placebo analgesia during a laboratory pain task. Healthy normotensive undergraduates (66 women, 68 men) who either did or did not report prior experience with pain from submerging a limb in cold water were enrolled. In the laboratory, an experimenter applied an inert, medicinal-smelling cream to participants&apos; non-dominant hand. Participants randomized to the no-expectation group were told that the cream was a hand cleanser. Participants randomized to the placebo expectation group were told that the cream would reduce the pain associated with the cold pressor task. Participants then completed the cold pressor task and reported their pain on the short form of the McGill Pain Questionnaire. Analysis of variance revealed a main effect of expectation (p < .05), such that participants in the placebo expectation group reported less pain. An interaction was also found between expectation and prior experience (p < .05), such that participants with prior experience with pain from cold water immersion showed no difference in pain reports between expectation groups. In a pain context, prior experience with the pain stimulus may prevent a placebo expectation from reducing the experience of pain. Keywords Pain * Placebo * Analgesia * Prior experience * Expectation * Cold pressor

We conclude that the heat shock response is enhanced in juvenile compared with adult rainbow trout, Oncorhynchus mykiss. We have shown that the magnitude of the inducible heat shock response, as measured by increases in the heat shock protein (Hsp) Hsp70 is significantly greater in the hearts of fingerling than in adult trout following an acute (1 h) heat stress at 25[degrees]C. Juvenile fish also express higher levels of constitutive Hsps (Hsc70, Hsp90) in their tissues, possibly reflecting higher rates of protein synthesis and increased chaperone function in this early life stage. This robust heat shock response in juvenile trout may contribute to a greater thermal resistance that is often observed in young salmonid fish. Nous concluons que la reaction au choc thermique est plus importante chez les truites arc-en-ciel, Oncorhynchus mykiss, juveniles que chez les adultes. Nous avons montre que l'intensite de la reaction induite par le choc thermique, mesuree par l'augmentation de la proteine du choc thermique (Hsp) Hsp70, est significativement plus elevee dans le ceur des fretins que dans celui des truites adultes suivant un stress thermique aigu (1 h) a 25[degrees]C. Les jeunes poissons ont aussi une expression de concentrations plus elevees d'Hsp constitutives (Hsc70, Hsp90) dans leurs tissus, ce qui reflete probablement des taux de synthese de proteines plus eleves et une fonction de chaperon plus importante a ce stage precoce de leur cycle biologique. Cette reaction robuste au choc thermique chez les jeunes truites peut contribuer a la resistance thermique plus elevee que l'on observe souvent chez les jeunes salmonides. [Traduit par la Redaction], Introduction Stream temperature is an important factor determining the abundance and distribution of cold-water fish species (de la Hoz Franco and Budy 2005). Although salmonid fish, like rainbow trout (Oncorhynchus [...]

Research indicates that when confronted with a health threat, individuals high in both dispositional and comparative optimism employ a more avoidant style of coping than individuals high in dispositional but low in comparative optimism. We examined the hypothesis that threat distance moderates this interactive optimism association. In two studies, participants were randomly assigned to a looming or distant threat condition. Study 1 revealed that in the looming threat condition, participants high in both forms of optimism were more likely to minimise the threat and less inclined to seek additional health information relative to participants high in dispositional but low in comparative optimism. In Study 2, the same interaction pattern emerged on a measure of psychological abstraction suggesting these variables combine to alter broad information processing strategies. Implications for considering multiple forms of optimism when delivering health status information are discussed. [ABSTRACT FROM AUTHOR]

ABSTRACT Every day we use products and treatments with unknown but expected effects, such as using medication to manage pain. In many cases, we have a choice over which products or treatments to use; however, in other cases, people choose for us or choices are unavailable. Does choosing (versus not choosing) have implications for how a product or treatment is experienced? The current experiments examined the role of choice-making in facilitating so-called expectation assimilation effects-or situations in which a person's experiences (e.g., discomfort and pain) are evaluated in a manner consistent with their expectations. In Experiment 1, participants were initially exposed to a baseline set of aversive stimuli (i.e., sounds). Next, some participants were given expectations for two 'treatments' (i.e., changes in screen display) that could ostensibly reduce discomfort. Critically, participants were either given a choice or not about which of the two treatments they preferred. Participants in a control condition were not provided with treatment expectations. Results revealed that discomfort experiences assimilated to expectations only when participants were provided with choice. Experiment 2 replicated this finding and provided evidence against the idea that demand characteristics and choice-making unrelated to the core task (i.e., choices without associated expectations) could account for the results. Further, Experiment 2 showed that choosing reduced discomfort because of increased positivity about the treatment. Results are discussed in the context of extant research on choice-making and expectation effects. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]