RESUMO
The effects of retention and demonstration intervals on serial position were evaluated in two experiments with Long-Evans rats. A list of 3 demonstrators that had eaten one of three flavored foods was presented to naive observers. In Experiment 1, there were four groups, three groups with a retention interval compared with one group with a zero retention interval or no retention interval. In Experiment 2, the demonstration interval was reduced. Intervals of 15, 5, 2, and 1 min were used. In Experiment 1, primacy decreased gradually in the four groups as the retention interval was increased in duration. In Experiment 2, primacy also decreased gradually, and recency occurred with the 1-min demonstrator interval. The increase in the duration of the retention interval reduced primacy. The reduction in the duration of the demonstration interval decreased primacy and produced recency.
Assuntos
Preferências Alimentares/fisiologia , Rememoração Mental/fisiologia , Retenção Psicológica/fisiologia , Aprendizagem Seriada/fisiologia , Comportamento Social , Análise de Variância , Animais , Atenção/fisiologia , Comportamento Animal/fisiologia , Feminino , Ratos , Ratos Long-Evans , Fatores de TempoRESUMO
Tobacco consumption is a world-wide public health problem that has been associated with different types of cancer, cardiovascular and respiratory diseases, alterations in the reproductive system, dental problems and some eye diseases. In Mexico the National Survey of Addictions (2002) reported that 26.4% of the urban population between 12 and 65 years and 14.3% of the rural population are smokers. The Secretary of Health indicated that more than 53000 people died from diseases related to tobacco consumption. The consumption of tobacco stands among the ten first causes of morbidity and mortality in Mexico. In this sense, smoking is considered as one of the main public health problems in Mexico. Several organisms and institutions have undertaken actions in an attempt to solve it, such as the development of educative programs directed to the general population and programs to help smokers to quit this habit. Some of the main strategies to reduce cigarette consumption include nicotine replacement therapy, therapy not based on nicotine (antidepressants, some opiate antagonists and anxiolytic drugs), psychological programs, and the combination of some of them. Regarding psychological treatments, behavioral and cognitive behavioral techniques for smoking cessation hold empirical evidence about their efficacy for reducing the abuse of substances. In Mexico, psychological, nicotinic and non-nicotinic treatments to stop smoking are used. Nevertheless, the methodological and theoretical grounds of the psychological interventions are not well-established and there are no specific data about the changes in the consumption pattern after the application of the interventions and whether the effects of the treatment stay through the time. Specifically, the information about the efficacy of the brief interventions on smokers in the Mexican population is scarce. Although different studies have demonstrated that the brief motivational interventions are more effective to reduce the abuse of different substances than intensive interventions or no interventions at all, the techniques are not widely used in the treatment of tobacco consumption in Mexican population. With this evidence, the National Autonomous University of Mexico (UNAM) developed the Brief Motivational Intervention Program to treat smokers. The Brief Motivational Intervention is based in the Social Cognitive Theory, the Prevention of Relapses Model, in techniques of motivational interview and self-control techniques. Therefore, the goal of the present research is to evaluate a brief motivational intervention program for smokers. In order to achieve this aim, 10 individuals between 19 and 55 years old participated in the program; five individuals showed low nicotine dependence and five severe nicotine dependence according to the Questionnaire of Fagerström Tolerance. There was a public invitation and the participants consent to participate voluntarily in the <
El consumo de tabaco es un problema de salud pública en el mundo y se le ha asociado con diferentes tipos de cáncer, enfermedades cardiovasculares, enfermedades respiratorias, alteraciones en el sistema reproductivo, problemas dentales, úlcera péptica y algunas enfermedades de los ojos. De acuerdo con la Encuesta Nacional de Adicciones de 2002, en México fuman 26.4% de las personas entre 12 y 65 años de la población urbana y 14.3% de la población rural. En este sentido, la Secretaría de Salud señala que en México fallecen anualmente más de 53 mil personas por enfermedades relacionadas con el consumo de tabaco, lo que lo ubica entre los diez primeros lugares de morbilidad y mortalidad. Entre los tratamientos propuestos para dejar de fumar se identifican las terapias sustitutivas con nicotina, las terapias farmacológicas, los tratamientos psicológicos y combinaciones de ellos. En relación con los tratamientos psicológicos, existe evidencia empírica que muestra la efectividad de las técnicas conductuales y cognitivo-conductuales para dejar de fumar. En México, se emplean tratamientos psicológicos y farmacológicos (nicotínicos y no nicotínicos) en personas que desean dejar de fumar. Sin embargo, en dichas intervenciones no se reportan datos específicos de los cambios en el patrón de consumo después de la aplicación de dichas intervenciones y si éste se mantiene a lo largo del tiempo. Asimismo, se sabe específicamente poco de la efectividad de las intervenciones breves dirigidas a fumadores en la población mexicana. Por lo tanto, en la presente investigación se evalúa un programa de intervención breve motivacional para fumadores que incide en el patrón de consumo de cigarros, en la percepción de la autoeficacia de los usuarios al finalizar la aplicación del programa y en el seguimiento a los seis meses. Para cumplir con el propósito se aplicó el programa de intervención breve motivacional a 10 personas de entre 19 y 55 años de edad que deseaban dejar de fumar. La evaluación del programa se realizó a partir de la comparación del patrón de consumo antes, durante y después de la aplicación de la intervención breve, así como del nivel de autoeficacia antes y después de la aplicación de la intervención breve. Un análisis de varianza (ANOVA) de medidas repetidas mostró cambios significativos en el patrón de consumo entre la línea base, intervención y seguimiento (F[2,18]=53.10, p<0.001). Posteriormente se realizaron comparaciones binarias con el ajuste de Bonferroni, lo cual indicó que las diferencias se ubicaron sólo entre la línea base con respecto al tratamiento (p<0.001) y la línea base con respecto al seguimiento (p<=0.001). En relación con el nivel de autoeficacia se encontraron diferencias significativas antes y después de aplicar la prueba Wilcoxon, y así se obtuvieron diferencias significativas en las siguientes situaciones: emociones desagradables (Z= 2.203, p< 0.05), malestar físico (Z = 2.492, p<0.05), conflictos con otros (Z= 2.556, p<0.05) y momentos agradables con otros (Z= 2.670, p<0.05), en las que incrementó el nivel de autoeficacia reportada en la segunda aplicación con respecto a la primera. Los resultados obtenidos en esta investigación concuerdan con los observados en la aplicación de intervenciones breves en otros países, pero específicamente con los obtenidos en México con bebedores problema, usuarios de cocaína y adolescentes que se inician en el consumo de drogas. El programa de intervención breve motivacional enfatiza el fortalecimiento de la autoeficacia y el modelo de prevención de recaídas, que mantiene el cambio de la conducta de consumo del usuario durante y después de la intervención. El usuario aprende a conceptualizar la recaída como parte de un proceso de cambio y no como un fracaso o un comportamiento adictivo que nunca podrá cambiar. Por lo anterior, el tratamiento para fumadores es una alternativa efectiva para su adopción en instituciones de salud y debe formar parte de las políticas preventivas para el tratamiento de fumadores en el ámbito nacional, ya que tiene un impacto específico en el patrón de consumo de cigarrillos y, en esa medida, en los daños orgánicos asociados a su consumo.
RESUMO
The serial position effect in Long-Evans rats was evaluated in two experiments. In Experiment 1, the effect in a group for which an interstimulus interval (ISI) was introduced between items in a list of demonstrators was compared with that in a group without an ISI. With an ISI, a recency effect was produced. In Experiment 2, a serial position effect group was compared with four groups in which either the distinctiveness or the context of the middle item was changed, relative to the items on either side of it. A von Restorff effect was produced when a rat from a different strain was used as a demonstrator in Position 2. The results for Experiment 1 are discussed in relation to interstimulus effects in monkeys and those for Experiment 2 with respect to changes in the physical properties of middle items.
Assuntos
Preferências Alimentares , Memória , Comportamento Social , Percepção Espacial , Animais , Comportamento Animal , Feminino , Ratos , Ratos Long-EvansRESUMO
There is evidence on the existence of sex differences in the serotonergic system of the raphe. This study examines sex-based differences in serotonergic activity in the dorsal (DRN) and median (MRN) raphe nucleus; two structures that have consistently been implicated in the brain circuitry associated with fear and anxiety reactions. We also analyzed the effects of the elevated plus-maze (EPM) test, which allows the measuring of behavioral reactions to stress on rats produced by fear to height and open spaces on such sex differences. The present study was carried out on 70- to 80-day-old rats exposed or not to the EPM test. Immediately after the test, or 10-12 days later, groups of animals were sacrificed to measure serotonin (5-HT) and 5-hydroxyindolacetic acid (5-HIAA) concentration in the DRN and MRN, to calculate the serotonergic activity ([5-HIAA]/[5-HT]). Serotonergic activity in the female's DRN was consistently higher than in male's DRN. Such differences were not observed in the MRN. While exposed to the EPM test, female rats display more aversive responses than males, only during the day of diestrus 1. After the EPM test, serotonergic activity decreased in the female's DRN and in the male's MRN, both immediately and 10-12 days later. The sex-based differences in fear/anxiety reported in this study could be linked to the observed decrease in serotonergic activity in the DRN of female rats after the EPM test.
Assuntos
Núcleos da Rafe/metabolismo , Serotonina/metabolismo , Caracteres Sexuais , Análise de Variância , Animais , Comportamento Animal , Cromatografia Líquida de Alta Pressão , Eletroquímica/métodos , Ciclo Estral/metabolismo , Feminino , Ácido Hidroxi-Indolacético/análise , Masculino , Aprendizagem em Labirinto , Núcleos da Rafe/anatomia & histologia , Ratos , Ratos WistarRESUMO
The effects of injecting testosterone propionate or estradiol benzoate to newborn rats on dopaminergic and serotoninergic activity in the frontal cortex, dorsal and median raphe nucleus were analyzed when animals reached adulthood. High performance liquid chromatography was used to measure tissue levels of dopamine, serotonin and its metabolites. Activity was calculated as the metabolite/neurotransmitter ratio. An increase in androgen or estrogen levels at birth caused a significant decrease in serotoninergic activity in the frontal cortex and in the dorsal raphe nucleus, without causing apparent changes in dopaminergic activity; serotinergic activity in the median raphe nucleus was not affected. The results suggest that the transmission of DA and 5-HT in these structures are differentially influenced by early androgenization or estrogenization.