Improving social interaction in chronic psychotic using discriminated avoidance ("nagging"): experimental analysis and generalization.
Three social-interaction behaviors of a withdrawn chronic schizophrenic were increased using a discriminated avoidance ("nagging") procedure. The three behaviors were: (a) voice volume loud enough so that two-thirds of his speech was intellibible at a distance of 3m; (b) duration of speech of at least 15 sec; (c) placement of hands and elbows on the armrests of the chair in which he was sitting. "Nagging" consisted of verbal prompts to improve performance when the behaviors did not meet their criteria. A combined withdrawal and multiple-baseline design was used to evaluate the effectiveness of the procedure, and the contingency was sequentially applied to each of the three behaviors in each of four different interactions to determine the degree of stimulus and response generalization. Results indicated that the contingency was the effective element in increasing the patient's appropriate performance, and that there was a high degree of stimulus generalization and a moderate degree of response generalization. After the patient's discharge from the hospital, the durability of improvement across time and setting was determined in followup sessions conducted at a day treatment center and at a residential care home. Volume and duration generalized well to the new settings, while arm placement extinguished immediately. (+info)
Central administration of rat IL-6 induces HPA activation and fever but not sickness behavior in rats.
Interleukin (IL)-6 has been proposed to mediate several sickness responses, including brain-mediated neuroendocrine, temperature, and behavioral changes. However, the exact mechanisms and sites of action of IL-6 are still poorly understood. In the present study, we describe the effects of central administration of species-homologous recombinant rat IL-6 (rrIL-6) on the induction of hypothalamic-pituitary-adrenal (HPA) activity, fever, social investigatory behavior, and immobility. After intracerebroventricular administration of rrIL-6 (50 or 100 ng/rat), rats demonstrated HPA and febrile responses. In contrast, rrIL-6 alone did not induce changes in social investigatory and locomotor behavior at doses of up to 400 ng/rat. Coadministration of rrIL-6 (100 ng/rat) and rrIL-1beta (40 ng/rat), which alone did not affect the behavioral responses, reduced social investigatory behavior and increased the duration of immobility. Compared with rhIL-6, intracerebroventricular administration of rrIL-6 (100 ng/rat) induced higher HPA responses and early-phase febrile responses. This is consistent with a higher potency of rrIL-6, compared with rhIL-6, in the murine B9 bioassay. We conclude that species-homologous rrIL-6 alone can act in the brain to induce HPA and febrile responses, whereas it only reduces social investigatory behavior and locomotor activity in the presence of IL-1beta. (+info)
Marijuana use among minority youths living in public housing developments.
Youths residing in public housing developments appear to be at markedly heightened risk for drug use because of their constant exposure to violence, poverty, and drug-related activity. The purpose of this study was to develop and test a model of marijuana etiology with adolescents (N = 624) residing in public housing. African-American and Hispanic seventh graders completed questionnaires about their marijuana use, social influences to smoke marijuana, and sociodemographic and psychosocial characteristics. Results indicated that social influences, such as friends' marijuana use and perceived ease of availability of marijuana, significantly predicted both occasional and future use of marijuana. Individual characteristics such as antimarijuana attitudes and drug refusal skills also predicted marijuana use. The findings imply that effective prevention approaches that target urban youths residing in public housing developments should provide them with an awareness of social influences to use marijuana, correct misperceptions about the prevalence of marijuana smoking, and train adolescents in relevant psychosocial skills. (+info)
Sex-biased dispersal in sperm whales: contrasting mitochondrial and nuclear genetic structure of global populations.
The social organization of most mammals is characterized by female philopatry and male dispersal. Such sex-biased dispersal can cause the genetic structure of populations to differ between the maternally inherited mitochondrial DNA (mtDNA) and the bi-parental nuclear genome. Here we report on the global genetic structure of oceanic populations of the sperm whale, one of the most widely distributed mammalian species. Groups of females and juveniles are mainly found at low latitudes, while males reach polar waters, returning to tropical and subtropical waters to breed. In comparisons between oceans, we did not find significant heterogeneity in allele frequencies of microsatellite loci (exact test; p = 0.23). Estimates of GST = 0.001 and RST = 0.005 also indicated negligible if any nuclear DNA differentiation. We have previously reported significant differentiation between oceans in mtDNA sequences. These contrasting patterns suggest that interoceanic movements have been more prevalent among males than among females, consistent with observations of females being the philopatric sex and having a more limited latitudinal distribution than males. Consequently, the typical mammalian dispersal pattern may have operated on a global scale in sperm whales. (+info)
Neurocognitive and social functioning in schizophrenia.
This cross-sectional study examined the relationships between neurocognitive and social functioning in a sample of 80 outpatients with DSM-III-R schizophrenia. The neurocognitive battery included measures of verbal ability, verbal memory, visual memory, executive functioning, visual-spatial organization, vigilance, and early information processing. Positive and negative symptoms were assessed with the Positive and Negative Syndrome Scale. A range of social behaviors were assessed using the Social Functioning Scale (SFS), the Quality of Life Scale (QLS), and a video-based test, the Assessment of Interpersonal Problem-Solving Skills (AIPSS). Social functioning as assessed by the SFS was unrelated to neurocognitive functioning. Poor cognitive flexibility was associated with low scores on the QLS and the AIPSS. Verbal ability and verbal memory were also significantly associated with the AIPSS. Visual-spatial ability and vigilance were associated with the sending skills subscale of the AIPSS. In this study, which used a wide range of neurocognitive tests and measures of community functioning and social problem solving, results support earlier research that suggests an association between certain aspects of neurocognitive functioning and social functioning. (+info)
Scaling in animal group-size distributions.
An elementary model of animal aggregation is presented. The group-size distributions resulting from this model are truncated power laws. The predictions of the model are found to be consistent with data that describe the group-size distributions of tuna fish, sardinellas, and African buffaloes. (+info)
Further analysis of the separate and interactive effects of methylphenidate and common classroom contingencies.
We evaluated separate and interactive effects between common classroom contingencies and methylphenidate (MPH) on disruptive and off-task behaviors for 4 children with a diagnosis of attention deficit hyperactivity disorder. Analogue conditions consisting of contingent teacher reprimands, brief time-out, no interaction, and alone were conducted in a multielement design. Medication status (MPH or placebo) was alternated across days in a superordinate multielement design. Results indicate that (a) the behavioral effects of MPH were influenced by one or more of the analogue conditions for each participant, and (b) time-out was associated with zero or near-zero levels of both disruptive and off-task behavior for 3 of the 4 participants during MPH and placebo conditions. Implications for the clinical effectiveness of MPH and possible behavioral mechanisms of action of MPH in applied settings are discussed. (+info)
The human amygdala plays an important role in gaze monitoring. A PET study.
Social contact often initially depends on ascertaining the direction of the other person's gaze. We determined the brain areas involved in gaze monitoring by a functional neuroimaging study. Discrimination between the direction of gaze significantly activated a region in the left amygdala during eye-contact and no eye-contact tasks to the same extent. However, a region in the right amygdala was specifically activated only during the eye-contact task. Results confirm that the left amygdala plays a general role in the interpretation of eye gaze direction, and that the activity of the right amygdala of the subject increases when another individual's gaze is directed towards him. This suggests that the human amygdala plays a role in reading social signals from the face. (+info)