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J L Díaz 《Behavioral and neural biology》1988,50(2):164-183
Fifty 8-week-old Balb/c mice were individually identified and housed together in a large and enriched environment for 5 months. Maze and open field exploration, response to an aversive noise, swimming, and induced grooming tests were applied to each mouse in an initial search for possible relationships between brain morphology and spontaneous behavior in isogenic individuals living in a complex social and physical environment. The tasks generated 39 quantitative behavioral indices which include locomotion, rearing, still, and grooming bout frequencies, latencies, total, and mean bout durations. At the end of the tests, the 7-month-old mice were sacrificed and the fresh weights of their whole brain, cerebellum, brain stem, diencephalon, telencephalon, and prosencephalon were rapidly obtained. Behavioral data have wide variations and do not adjust to normal population distributions. Means of the same parameter differ between tests. A Spearman correlation matrix of all data yielded many significant correlations between indices of the same task which can be interpreted in terms of time budget and sequence probability. Significant correlations between indices of different tests suggest diverse emotionalities, exploratory strategies, and motor skills. The correlations between body and brain weights and among separate brain regions were not significant. There were several low but significant correlations between brain weights and behavioral indices. Such correlations, the resulting factors, and significant behavioral differences between mice with large and small brains suggest that mice displaying low motor activity in novel environments have larger brains and forebrain/hindbrain ratios than mice with high activity, and that animals with high scores of some specific behaviors have larger brain areas physiologically related to such behaviors.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
3.
The Companeros model of HIV infection prevention in Ciudad Juarez, Mexico, is presented as conceived by the National Institute of Drug Abuse (NIDA). 518 women who were IV drug users, sexual partners of drug addicts, or prostitutes were requested to participate, and 232 consented. Initial and follow-up AIDS assessments were utilized along with an assessment of sociodemographic variables, including knowledge, sexual behavior, use and abuse of drugs, and previous health history. Educative sessions about AIDs and sexually transmitted diseases (STDs) included group discussions and interaction, video watching, personal experiences, and sociodramas. 61% of prostitutes were 29, 12.6% were 13-19 years old, 31.1% were aged 30-39, and 8.9% were 40. 11% had no formal education, 58% had 6 years of primary and part of 3 years of secondary education, only 18.6% completed secondary education; and 13% had higher education. 19% lived in a hotel or shelter. Family disintegration reached 44%; these women did not live with their children. Only 5.2% thought they had excellent health, 51% said they had good health, 31% stated they had average health, and 12% admitted having had health problems. 14.6% had genital ulcers, 1.3% had herpes, 15% had gonorrhea, and 10% had syphilis. Since IV drug use among these women was almost nonexistent sexual relations constituted the principal risk factor. Responses to a questionnaire showed that the most frequent sexual behavior was vaginal penetration followed by fellatio; anal penetration was less common. 34.9% of the women practiced fellatio without protection, 16.3% had anal intercourse without protection. The proportion of AIDS cases in Mexico in women of reproductive age was growing at an exponential rate, possible because of misinformation about AIDS, a history of STDs, and a low rate of condom use. 相似文献
4.
Edgar Elías Osuna 《Journal of mathematical psychology》1985,29(1):82-105
The study of any problem involving waiting situations invariably assumes that people dislike having to wait. The analysis of queueing problems usually prescribes that some costs should be associated with the time people spend waiting to be served. These are usually considered to be of an economic nature, though the existence of other costs of a psychological nature is accepted. It is generally accepted that after having to wait for a certain amount of time, anxiety and stress start to build up in an individual, due both to the sense of waste and the uncertainty involved in a waiting situation. This work provides a theoretical basis for analysing this building up process as it occurs during the waiting period. It is proved that, under very general conditions, the resulting psychological stress accumulated during the process is a marginal increasing function of the waiting time, and some strategies to minimise it are developed. The results obtained give theoretical support to the usual assumptions underlying the development of systems to provide “real time” information to people in waiting situations. This is especially important in the operation of public transportation systems. The results also provide theoretical support to the “convex” treatment usually given to the waiting cost function in queueing problems. 相似文献
5.
Some features of social living were investigated in three inbred strains of mice: C57Bl/6j, Balb/cj, and NIH. Five social behaviors--Aggression, Submission, Allogrooming, Social Rest and Rest Alone, as well as Wheel Running Activity--were recorded 2 h daily for a week, in 26 groups of seven male mice living in an enriched environment. Dominants and subordinates among strains shared some behavioral characteristics, but strain contributions upon social structure were also detected. Similarities among strains included the appearance of a single dominant mouse per group rated as the most aggressive, besides from being the animal presented with most Submissions. Allogrooming was more frequent among subordinates than among dominants and subordinates. Differences among strains were that agonistic behavior among subordinates was higher in the Balb/cj and NIH groups than in the C57Bl/6j mice. NIH mice were recorded in Rest Alone more often than mice from the other strains. C57Bl/6j dominants showed higher rates of Wheel Running Activity than subordinates. 相似文献
6.
Pigeons' responses were reinforced on a variant of a mixed variable-interval extinction schedule of reinforcement in which the transition to the higher reinforcement rate was signaled by a trace stimulus projected on the response key prior to the onset of the component correlated with food delivery. In the first of two experiments, the duration of the trace stimulus preceding the component correlated with food delivery was varied from 1.5 to 50.0 s and in the second experiment, the reinforcement frequency in the same component was varied from 10 to 60 reinforcers per hour. Pigeons pecked at the trace stimulus preceding the onset of the component correlated with food delivery even though responding was not reinforced in its presence and only one of the changes in reinforcement rate (i.e., from extinction to reinforcement) was signaled. The rate of pecking during the trace stimulus was a function of its duration but not of the reinforcement frequency in the following component. Higher rates generally occurred at the shorter trace-stimulus durations. Component responding following the offset of the trace stimulus was under discriminative control of the trace stimulus whether or not responding occurred in the presence of the trace stimulus. 相似文献
7.
Miguel A. García-Pérez 《Behavior research methods》1987,19(1):42-46
In this paper, we present a BASIC program for Apple II series computers that allows the user to obtain perspective drawings of two-dimensional functions of known analytical expression. Also, we outline a procedure for obtaining perspective representations of two-dimensional arrays of data using the same program. The program should run on any computer with graphics mode with only slight modifications in the graphics commands. 相似文献
8.
The present investigation sought to further delineate the Type A coronary-prone behavior pattern and to elucidate the psychophysiological process through which this behavioral disposition is translated into heart disease. Type A and Type B male subjects engaged in tasks that required varying degrees of activity before an assessment of challenge-seeking tendencies. Type A participants sought greater degrees of challenge than did their Type B counterparts. In addition, the more active the person with Pattern A had been immediately before the challenge-seeking opportunity, the greater the degree of challenge sought. Precedent activity level did not significantly influence challenge seeking in the Type B population. The Type A subjects also had significantly faster heart rates during performance of a challenging task. Pattern A behavior may be translated into heart disease through the cumulative deleterious effects of chronic and excessive challenge-induced cardiovascular excitation. 相似文献
9.
One of the most serious psychosocial problems worldwide is substance abuse because of its repercussions not only on the physical and psychological health of the abuser but also on their relational functioning. Among the well-established therapeutic approaches for the treatment of substance abuse is family therapy, which, in addition to influencing personal variables, promotes changes in family dynamics. The main objective of this study is to review the scientific literature published from 2010 to the present on the efficacy and effectiveness shown by family-based treatment approaches for substance use problems both in adolescent and adult samples. In addition, the effect on secondary variables such as family functioning and behavioral problems is evaluated. The empirical evidence accumulated in the last decade and reviewed in the present study indicates that the incorporation of family members in the treatment of substance abuse produces benefits by diminishing consumption and improving family functioning. Limitations of this study and of the research reviewed are discussed and directions for future research are provided. 相似文献
10.
Yolanda van Beek David Hessen Lisa Levelt Daniëla Beijer Corine Rijnberk Athanasios Maras Mathilde M. Overbeek 《Journal of Family Therapy》2023,45(3):271-290
The effectiveness of intense specialised multi-family therapy (ISMFT) for 111 multi-stressed families, and the therapeutic alliance as a possible predictor of outcome, were examined. A repeated measures design was used, where changes in all ISMFT phases (preparation, multi-family therapy and follow-up) were assessed and compared for both mothers and fathers. Evidence was found for improved family functioning after the therapy period, which was maintained at 3 months follow-up, although the multi-stressed families still functioned in the problematic range. The therapy did however not decrease parenting stress, or did so only temporarily. Observations of the therapeutic alliance with the System for Observing Family Therapy Alliances (SOFTA) scales indicated that high therapist engagement was related to positive therapy outcomes, both at the start of therapy and later. High family engagement also predicted therapy effectiveness, but only at the start of therapy. The present study shows that solution-focused multi-family therapy at least seems to provide the first step in alleviating problems in multi-stressed families. 相似文献