RESUMO
Radiation-induced taste aversion has been suggested to possibly play a role in the dietary difficulties observed in some radiotherapy patients. In rats, these aversions can still be formed even when the radiation exposure precedes the taste experience by several hours. This study was conducted to examine whether increasing the radiation exposure level could extend the range of the exposure-taste interval that would still support the formation of a taste aversion. Separate groups of rats received either a 100 or 300 R gamma-ray exposure followed 1, 3, 6, or 24 h later by a 10-min saccharin (0.1% w/v) presentation. A control group received a sham exposure followed 1 h later by a 10-min saccharin presentation. Twenty-four hours following the saccharin presentation all rats received a series of twelve 23-h two-bottle preference tests between saccharin and water. The results indicated that the duration of the exposure-taste interval plays an increasingly more important role in determining the initial extent of the aversion as the dose decreases. The course of recovery from taste aversion seems more affected by dose than by the temporal parameters of the conditioning trial.
Assuntos
Condicionamento Clássico/efeitos da radiação , Paladar/efeitos da radiação , Animais , Relação Dose-Resposta à Radiação , Raios gama , Masculino , Doses de Radiação , Ratos , Ratos Endogâmicos , Sacarina , Fatores de Tempo , ÁguaRESUMO
Depressed college students were compared with other-psychopathology and normal controls regarding the relationship they developed with dormitory roommates during a 9-month period. Diagnostic status was periodically assessed via SADS interviews, thus also permitting identification of new cases of depression during the year. Psychosocial characteristics found to be uniquely associated with current depression were: (a) low social contact with roommates, (b) low enjoyability of these contacts, and (c) high life-event stress. Roommates of depressives reported low enjoyability of the relationship and high levels of aggressive behavior towards the depressive. No features were found to be uniquely associated with new cases before they became depressed; however, several antecedents of general psychopathology were identified.
Assuntos
Transtorno Depressivo/psicologia , Relações Interpessoais , Adulto , Feminino , Humanos , Masculino , Testes Psicológicos , Fatores de RiscoRESUMO
Seventy-two hours after saccharin (CS) was paired with either a 100R or sham radiation exposure, rats received a 0-, 3-, 6-, 12-, 24-, or 46-hour saccharin-alone presentation followed by a 23-hour two-bottle preference test. Generally, faster recovery from the aversion was observed in animals receiving longer CS-alone presentations. The present procedure differs from previous work done with other toxins in that animals were not fluid-deprived during the postconditioning period. This enabled animals to constantly control the volume, duration, and inter-bout interval of the saccharin drinking episodes independent of any experimentally imposed drinking schedule. In addition, the two-bottle test provided a sensitive measure of the status of the saccharin aversion following the saccharin-alone presentation.