Second-order schedules of token reinforcement with pigeons: effects of fixed- and variable-ratio exchange schedules

Pigeons' key pecks produced food under second-order schedules of token reinforcement, with light-emitting diodes serving as token reinforcers. In Experiment 1, tokens were earned according to a fixed-ratio 50 schedule and were exchanged for food according to either fixed-ratio or variable-ratio exchange schedules, with schedule type varied across conditions. In Experiment 2, schedule type was varied within sessions using a multiple schedule. In one component, tokens were earned according to a fixed-ratio 50 schedule and exchanged according to a variable-ratio schedule. In the other component, tokens were earned according to a variable-ratio 50 schedule and exchanged according to a fixed-ratio schedule. In both experiments, the number of responses per exchange was varied parametrically across conditions, ranging from 50 to 400 responses. Response rates decreased systematically with increases in the fixed-ratio exchange schedules, but were much less affected by changes in the variable-ratio exchange schedules. Response rates were consistently higher under variable-ratio exchange schedules than tinder comparable fixed-ratio exchange schedules, especially at higher exchange ratios. These response-rate differences were due both to greater pre-ratio pausing and to lower local rates tinder the fixed-ratio exchange schedules. Local response rates increased with proximity to food under the higher fixed-ratio exchange schedules, indicative of discriminative control by the tokens.     

Behavioral and pharmacological variables affecting risky choice in rats.

The effects of manipulations of response requirement, intertrial interval (ITI), and psychoactive drugs (ethanol, phencyclidine, and d-amphetamine) on lever choice under concurrent fixed-ratio schedules were investigated in rats. Responding on the "certain' lever produced three 45-mg pellets, whereas responding on the "risky" lever produced either 15 pellets (p = .33) or no pellets (p .67). Rats earned all food during the session, which ended after 12 forced trials and 93 choice trials or 90 min, whichever occurred first. When the response requirement was increased from 1 to 16 and the ITI was 20 s, percentage of risky choice was inversely related to fixed-ratio value. When only a single response was required but the ITI was manipulated between 20 and 120 s (with maximum session duration held constant), percentage of risky choice was directly related to length of the ITI. The effects of the drugs were investigated first at an ITI of 20 s, when risky choice was low for most rats, and then at an ITI of 80 s, when risky choice was higher for most rats. Ethanol usually decreased risky choice. Phencyclidine did not usually affect risky choice when the ITI was 20 s but decreased it in half the rats when the ITI was 80 s. For d-amphetamine, the effects appeared to he related to baseline probability of risky choice; that is, low probabilities were increased and high probabilities were decreased. Although increase in risky choice as a function of the ITI is at variance with previous ITI data, it is consistent with foraging data showing that risk aversion decreases as food availability decreases. The pharmacological manipulations showed that drug effects on risky choice may be influenced by the baseline probability of risky choice, just as drug effects can be a function of baseline response rate.     

Does Differential Cohort Socialization Matter? The “Age Invariance” Hypothesis and Political Socialization

In classical and contemporary social theory alike, the key to understanding how cultural change comes about has been thought to lie in the long-term effect of differential cohort socialization. Cultural change is thought to proceed as differently socialized cohorts replace each other in the course of time. Moreover, distinct generations have been claimed to emerge. Thisarticle addresses the impact of cohort replacement and the presence of generations, including discussions of the theoretical framework underlying these concepts and the problem of disentangling age, period, and cohort effects. Analyses of Dutch survey data substantiate that cohort membership matters. Yet the impact of cohort replacement on cultural change turns out to be limited, and little evidence is found in support of the idea that specific generations arediscernible.     

Culture Is More than a Static Residual: Introduction to the Special Section on Culture and Foreign Policy

The literature on international relations frequently refers to culture in broad, macro-level ways to explain what cannot be explained by economic or military power. The assumptions that culture is simple, uniform and the opposite of power are, in the view of the authors, erroneous. Also, the authors note that there is a lack of scholarly interaction among psychologists interested in cross-cultural phenomena and international relations specialists interested in questions of identity and foreign policy. As an introduction to a special section on culture and foreign policy, this article calls for more communication among these scholarly communities; provides a set of observations about foreign policy and culture understood as a complex, dynamic concept; and calls for specific kinds of studies to better understand foreign policy in the context of cultural complexity and richness.     

儿童对抽象画情绪寓意理解的发展及文化因素的影响

本实验旨在探索儿童对抽象图画情绪寓意敏感性的发展规律以及文化因素的影响。被试年龄跨度从 5岁至高中学生。根据被试利用形态、主题、情绪等图片特性作为识辨依据的特点来发现规律。儿童对抽象图画寓意敏感性的发展与表征水平相关。年幼儿童只能利用颜色或图形等单一信息维量进行判断 ,年长儿童及中学生可以综合利用形态、主题、情绪等多个维量判断。在寓意明确的图片识辨中 ,儿童对积极寓意的识辨成绩较优。在双关寓意的图片识辨中 ,儿童组倾向于选择具有积极寓意的线索 ,而中学生组会受到识辨经验的影响。文化与教育方式影响儿童对抽象图画情绪寓意的理解。中国幼教方式有助于儿童对图画认知与情绪成分的识辨。     

Anxiety Symptomatology in Mexican-American Adolescents

Mexican-American adults and adolescents in general have been reported to have high levels of anxiety symptomatology. In our study of a tri-ethnic sample of 2528 junior and senior high school students, the Youth Self Report (YSR) version of the Child Behavior Checklist (CBCL) and a sociodemographic questionnaire was used to assess the anxiety symptoms of Hispanic youth. We compared the ratings on anxiety symptoms, using Achenbach's anxiety subscale on the YSR, between two populations. The anxiety levels of youth in coastal southeast Texas (Galveston County) were compared to the anxiety levels of youth in the lower Rio Grande Valley. We found that Mexican-Americans of the Lower Rio Grande Valley scored higher on anxiety symptoms than the tri-ethnic population of Galveston County. Other factors associated with higher anxiety scores for Mexican-American youths included being born outside the US, linguistic fluency, father absent from the home, mother's education, and household size. Multiple regression analyses showed that socio-economic status (SES), family composition, and linguistic fluency had a greater relative impact on anxiety symptomatology than all other factors, both for the total sample as well as for the Mexican-American sample. These results parallel previous findings, with Mexican-American adults, which suggest either higher risk for anxiety symptomatology or a culturally related bias in the reporting of such symptoms.     

Exploring Decision Making Around Therapist Self‐Disclosure in Cognitive Behavioural Therapy

Background

Therapist self‐disclosure (TSD) usage varies greatly among different psychotherapy orientations. Anecdotal evidence seems to suggest that there are reasons for its judicious use, and a small number of researchers have proposed guidelines for how TSD should be used to help therapists across psychotherapy models make decisions around disclosure. However, there is almost no literature specifically exploring how cognitive behaviour therapy (CBT) practitioners make decisions around employing TSD within the CBT framework.

Objective

This study aimed to explore how experienced CBT practitioners make decisions around TSD.

Method

In‐depth qualitative interviews were conducted with six clinical psychologists who were trained and experienced in CBT, and the interviews were analysed thematically.

Results

There were two overarching themes in terms of how they made decisions to self‐disclose: (A) the rules for TSD use, which included sub‐themes (a) it must have a clear purpose, (b) it must fit, (c) the therapist must maintain boundaries, and (d) the therapist must always reflect on his/her use of TSD; and (B) how they use TSD, which included subthemes of (a) using it as a tool for change and (b) using it to manage the therapeutic relationship.

Conclusion

Participants’ decisions on whether or not to self‐disclose were strongly influenced by the CBT model, and this process went beyond what is suggested in the transtheoretical literature. Understanding this process may lead to the development of CBT‐specific guidelines for making TSD‐related decisions.     

A Systematic Review: Non‐Suicidal Self‐injury in Australia and New Zealand's Indigenous Populations

Objective

To undertake a systematic review of non‐suicidal self‐injury (NSSI) prevalence, patterns, functions, and behavioural correlates for the Indigenous populations of Australia (Aboriginal and Torres Strait Islanders) and New Zealand (NZ; Maori).

Method

We searched the following electronic databases: PubMed, MedLine, Scopus, Web of Science, ScienceDirect, PsycInfo, and PsycArticles, CINAHL, and the Informit Health and Indigenous Peoples collections. Studies were included for review if they were published within the last 25 years and reported on NSSI in Australia and NZ's Indigenous populations.

Results

Seven studies were included, six of which came from Australia. The prevalence of NSSI in Australia ranged from 0.9% up to 22.50%; statistics varied by the different samples, types of prevalence, and relationship to alcohol. Several studies found that Aboriginal and Torres Strait Islander peoples had higher rates of NSSI than other Australians, but that this was not significantly higher. Two studies indicated that NSSI was linked to alcohol use, incarceration, and a younger age. The one NZ study was of injury and not specifically NSSI.

Conclusions

Findings are limited due to a small pool of literature. Cultural variations in NSSI presentation should be considered when working with Indigenous populations. Further research is required to help determine what cultural variations may exist.