The devaluation effect: activating a need devalues unrelated objects

It is commonly assumed that an object capable of satisfying a need will be perceived as subjectively more valuable as the need for it intensifies. For example, the more active the need to eat, the more valuable food will become. This outcome could be called a valuation effect. In this article, we suggest a second basic influence of needs on evaluations: that activating a focal need (e.g., to eat) makes objects unrelated to that need (e.g., shampoo) less valuable, an outcome we refer to as the devaluation effect. Two existing studies support the existence of a devaluation effect using manipulations of the need to eat and to smoke and measuring attractiveness of consumer products and willingness to purchase raffle tickets. Furthermore, the evidence suggests that consumers are not aware of the devaluation effect and its influence on their preferences.

Nonthymoma-associated exfoliative dermatitis in 18 cats.

BACKGROUND Exfoliative dermatitis has been described in cats as a paraneoplastic skin disease associated with thymoma. There are anecdotal reports of cases without thymoma, with various suspected aetiologies. HYPOTHESIS/OBJECTIVES To identify common features, underlying causes, response to therapy and outcome of nonthymoma-associated exfoliative dermatitis in cats. METHODS Retrospective analysis was carried out of cases presented to dermatology referral centres or cases submitted for histopathological examination. Detailed historical and clinical data were obtained and evaluated statistically. Histopathology was reviewed in a blinded fashion by three dermatopathologists, and PCR for herpesvirus was performed. RESULTS Eighteen cats fulfilled all inclusion criteria. There was no sex, age or breed predisposition. All cats presented with severe generalized (77%) or multifocal exfoliation (23%); 12 cats were severely depressed. In all cats, thymoma was excluded radiographically and feline leukaemia virus tests were negative. Additional imaging procedures in 14 cats and postmortem examination in two cats did not detect neoplasia. Histopathology revealed interface dermatitis, mural interface folliculitis and sebaceous adenitis indistinguishable from findings in thymoma-associated cases. PCR for herpes DNA was negative. No aetiology was identified. Treatment in 12 cases consisted of immunosuppressive doses of corticosteroids and/or ciclosporin; one responded to antibiotics, one to shampoo, two went into spontaneous remission, and two did not receive any therapy and were euthanized. CONCLUSIONS AND CLINICAL IMPORTANCE Nonthymoma-associated exfoliative dermatitis in cats is clinically and histopathologically indistinguishable from thymoma-associated cases. Most cases benefit from immunosuppressive therapy; therefore, an immunopathological response to an undefined trigger is suspected.