Time, trace, memory

Objections to a trace hypothesis for interval timing do not apply to the multiple-time-scale (MTS) theory, which incorporates a dynamic trace tuned by the system history and can easily accommodate interval timing over a 1,000:1 range. The MTS model can also account for Weber's law as well as systematic deviations from it. Contrary to our critics, we contend that patterns of variance in interval timing experiments are not fully described by scalar expectancy theory, and that attempting to understand timing by assigning variance to different elements of a flexible model that lacks inductive support is a flawed strategy, because the attempt may be successful even if the model is wrong. We further argue that biological plausibility is an unreliable guide to the development of behavioral theory, that prediction is not the same as test, that induction should precede deduction, and that a rat is not a clock.     

Multiple determinants of the effects of reinforcement magnitude on free-operant response rates

Four experiments examined the effects of increasing the number of food pellets given to hungry rats for a lever-press response. On a simple variable-interval 60-s schedule, increased number of pellets depressed response rates (Experiment 1). In Experiment 2, the decrease in response rate as a function of increased reinforcement magnitude was demonstrated on a variable-interval 30-s schedule, but enhanced rates of response were obtained with the same increase in reinforcement magnitude on a variable-ratio 30 schedule. In Experiment 3, higher rates of responding were maintained by the component of a concurrent variable-interval 60-s variable-interval 60-s schedule associated with a higher reinforcement magnitude. In Experiment 4, higher rates of response were produced in the component of a multiple variable-interval 60-s variable-interval 60-s schedule associated with the higher reinforcement magnitude. It is suggested that on simple schedules greater reinforcer magnitudes shape the reinforced pattern of responding more effectively than do smaller reinforcement magnitudes. This effect is, however, overridden by another process, such a contrast, when two magnitudes are presented within a single session on two-component schedules.     

Variable-ratio schedules of timeout from avoidance: effects of d-amphetamine and morphine.

Rats were trained on concurrent schedules in which pressing one lever postponed shock and pressing the other lever produced periods of signaled timeout from avoidance on variable-ratio schedules. These procedures generated high rates of timeout-reinforced responding and provided a baseline for studying the effects of drugs on behavior maintained by different types of negative reinforcement (shock postponement vs. timeout). Morphine (2.5 to 10.0 mg/kg) reduced behavior maintained by timeout at doses that increased or had no effect on avoidance responding. In contrast, d-amphetamine (0.125 to 2.0 mg/kg) produced large increases in timeout responding at doses that had minimal effect on avoidance in rats trained on variable-interval and variable-ratio schedules. Thus, the event-dependent effects of morphine, observed in previous studies in which timeout responding was maintained at low rates by interval schedules, were replicated with high timeout rates maintained by variable-ratio schedules. The effects of d-amphetamine could also be described as "event dependent" because timeout responding was stimulated more than avoidance regardless of the maintenance schedule or baseline rate.     

Choice and the dependability of stimuli that predict shock and safety

This study assessed whether choosing a signalled shock condition over an unsignalled one is controlled by a stimulus that predicts the presence of shock (Experiment I), or by a stimulus that predicts the absence of shock (Experiment II). The dependability of these stimuli as predictors of either the presence or the absence of shock was parametrically varied over a wide range, and subjects (rats) were given an option to change from an unsignalled to a signalled condition. In the first experiment, all shocks were preceded by signals; however, the probability of a signal being followed by shock varied from 1.0 to 0.02. The data obtained indicate that the dependability of the signal as a predictor of shock is unimportant. Rats changed to the signalled condition when the signal was completely dependable (all signals followed by shock) and when the dependability of the signal was systematically degraded. In the second experiment, all signals were followed by shock; however, some shocks were not preceded by a signal. The data show that the dependability of a stimulus predicting the absence of shock is important in that, as dependability decreases, changing to the signalled condition also decreases.     

Self-control in male and female rats

Eight male and 8 female Wistar rats were exposed to a discrete-trial procedure in which they chose between the presentation of a small (one pellet) or a large (three pellets) reinforcer. The delay to the small and large reinforcer was 6.0 s in the first condition of Experiment 1. Subjects consistently chose the large reinforcer. When the delay to the small reinforcer was decreased to 0.1 s in the next experimental condition, all subjects continued to choose the large 6.0-s delayed reinforcer. When the contingencies correlated with the two levers were reversed in the next experimental condition, the majority of subjects (5 males and 6 females) still chose the large delayed reinforcer over the small immediately presented reinforcer. The delay to the small reinforcer was maintained at 6.0 s, but the delay to the large reinforcer was varied among 9.0, 15.0, 24.0, and 36.0 s in Experiment 2, in which 4 males and 4 females participated. Most subjects consistently chose the large increasingly delayed reinforcer, although choice for the small 6.0-s delayed reinforcer developed in some females when the large reinforcer was delayed for 24.0 or 36.0 s. These choice patterns were not predicted from a literal application of a model that says choice should favor the alternative correlated with the higher (amount/delay) ratio.     

Does witnessing gender discrimination predict women's collective action intentions for gender justice? Examining the moderating role of perceived female support

Previous research has indicated that witnessing gender discrimination may instigate women's participation in collective action for gender justice. However, relatively little is known about the role of perceived female support in motivating collective action among women who witness gender discrimination in public life. This study aims to analyse whether and when perceived support from feminist-minded women moderates the association between women's witnessing gender discrimination and their willingness to engage in collective action for gender justice. We argue that the association between witnessing gender discrimination and willingness to engage in collective action depends on the support women perceive from their female friends and family members. In studies of women in the U.S. (Study 1; N = 271) and Ukraine (Study 2; N = 256), witnessing gender discrimination predicted greater willingness to participate in collective action for gender justice, and this association was stronger when female support was perceived to be lower. Study 3 (N = 1,304) replicated the findings of Studies 1 and 2 with self-identified feminist women in Turkey. Our research offers novel insights regarding why perceived lack of female support may encourage women to engage in collective action for gender justice.     

Female exhibitionism: identification, competition and camaraderie

The ancient figure of Baubo plays a pivotal role in the Greek myth of Demeter and Persephone with an exhibitionistic act that brings Demeter out of her depression. The Baubo episode raises questions about the meaning of female exhibitionism, suggesting divergences from earlier psychoanalytic conceptualizations as either a perversion or a compensation for the lack of a penis. In line with contemporary thinking about primary femininity, such as that of Balsam or Elise, the authors propose a more inclusive understanding of female exhibitionism, which would encompass pleasure in the female body and its sexual and reproductive functions. They argue that female exhibitionism can reflect triangular or "oedipal" scenarios and the need to attract the male, identification with the mother, competition or camaraderie with other women, a sense of power in the female body and its capacities, as well as homoerotic impulses. The authors posit a dual early desire and identification with the mother that underlie and characterize female sexual development. The authors present clinical data from adolescent and adult cases of female exhibitionism which illustrate these Baubo-like aspects and discuss the technical issues that are involved in such cases.     

The HoST programme: A pilot evaluation of modified dialectical behaviour therapy with female offenders diagnosed with borderline personality disorder

The Holloway skills therapy programme (HoST) at Her Majesty’s Prison and Young Offenders’ Institution Holloway is provided to women who, because of problematic behaviour associated with borderline personality disorder, are often excluded from treatment in prison and in the community. HoST addresses issues of offending behaviour, self-harm, suicidality and indiscipline, through a modified evidence-based treatment modality, dialectical behaviour therapy (DBT), which is a form of cognitive behaviour psychotherapy. This paper will outline the possibility of a modified DBT approach to working with female offenders in the prison setting. A pilot evaluation of female prisoners who received the treatment is also presented through a range of quantitative measures. In turn, positive outcomes with regard to reduction in time spent on the assessment and care in custody teamwork process, reduction in adjudications and improved overall mental health are presented. These findings are discussed along with the implications for clinical practice in the prison setting. The need for future structured research is also discussed.     

Exploring the Intersecting Health Risks of Substance Abuse,Sexual Risk,and Violence for Female South African Teen Dropouts

The study sought to better understand the cultural contexts of the risks for adolescent females who have dropped out of school. Focus groups were conducted with 37 Black and Coloured females aged 13 to 17 in Cape Town, South Africa. Data were analysed using content analysis. Methamphetamine, cannabis, and alcohol were used by both, however, Black teens also used methaqualone and Coloured teens used heroin and ecstasy. Some teens traded sex for drugs and others did so at the request of their drug-addicted mothers. Teens revealed high rates of violence, including rape, and many myths and barriers about condom use, revealing risky sex behaviours. Conclusion—Cultural nuances between the two groups will help inform the adaptation of an HIV prevention intervention.