Exploratory behavior as a function of environmental novelty and complexity in male and female rats

Laboratory rats show a positive response to low- and nonstressful novel events. The novel event may involve a number of aspects of the stimulus field. It is usually associated with a change in amount of environmental complexity. Most studies concerning novelty-related behavior involve the introduction of novel objects or the rearrangement of familiar objects. The present purpose was to measure exploratory behavior in response to environments of increased and decreased complexity. Both directions of environmental change are conditions of novelty. A two-way manipulation of increasing and decreasing the complexity of the environment was used. Rats of both sexes showed increased exploration to exposure to novelty, no matter which manipulation was applied; however, female and male rats behaved differently to the two types of novelty. Males responded more to novelty from the introduction of an unfamiliar object. The results indicate novel stimulation, whether of increasing or decreasing complexity, has reward properties. Perhaps the male-specific behavior directed toward unfamiliar objects may serve an adaptive function.     

Using a psychoeducational approach to increase the self-esteem of adolescents at high risk for dropping out

The effectiveness of an ecologically oriented approach in changing the self-concepts of 80 high-risk adolescents was investigated. Participants were administered a self-esteem scale before and after an eight-week psychoeducational program designed for dropout prevention. Results indicated significant reductions in dropout rates and increased self-esteem among participants.     

Do readers make inferences about conversational topics?

When we read that two protagonists in a story chatted together for a couple of minutes, do we draw inferences about the topic of the conversation on the basis of information presented earlier in the text? Participants read passages in which protagonists part and later reunite; the passages ended with a sentence either that implied conversation or did not. In Experiment 1, participants' continuation sentences indicated that inferences about the topic of conversation were drawn. Recognition probe data in Experiment 2 provided more immediate evidence of such inferences. Experiment 3 addressed a possible confound in Experiment 2 and again provided evidence that readers inferred the continuation of the conversation. In Experiments 4 and 5, we investigated the effect of having the targeted conversational topic be a secret that should not be shared between the protagonists. The results are discussed in terms of the collaboration between passive, memory-based text processing and schema-driven comprehension processes.     

The coming of age of telecommunications in psychological research and practice

Rapid and far-reaching technological advances are revolutionizing the ways in which people relate, communicate, and live their daily lives. Technologies that were hardly used a few years ago, such as the Internet, e-mail, and video teleconferencing, are becoming familiar methods for modern communication. Telecommunications will continue to evolve quickly, spawning telehealth applications for research and the provision of clinical care in communities, university settings, clinics, and medical facilities. The impact on psychology will be significant. This article examines the application of developing technologies as they relate to psychology and discusses implications for professional research and practice.     

Sequential learning models for the Wisconsin card sort task: Assessing processes in substance dependent individuals

The Wisconsin card sort task (WCST) is a commonly used neuropsychological test of executive or frontal lobe functioning. Traditional behavioral measures from the task (e.g., perseverative errors) distinguish healthy controls from clinical populations, but such measures can be difficult to interpret. In an attempt to supplement traditional measures, we developed and tested a family of sequential learning models that allowed for estimation of processes at the individual subject level in the WCST. Testing the model with substance dependent individuals and healthy controls, the model parameters significantly predicted group membership, even when controlling for traditional behavioral measures from the task. Substance dependence was associated with (a) slower attention shifting following punished trials and (b) reduced decision consistency. Results suggest that model parameters may offer both incremental content validity and incremental predictive validity.     

Rats’ visual-spatial working memory: New object choice accuracy as a function of number of objects in the study array

When rats had to find new (jackpot) objects for rewards from among previously sampled baited objects, increasing the number of objects in the sample (study) segment of a trial from 3 to 5 and then to 7 (Experiment 1) or from 3 to 6 and 9 (Experiments 2 and 3) or from 6 to 9 and 12 (Experiment 4) did not reduce rats’ test segment performance. Increasing study segment size improved test segment performance contrary the limited-capacity hypothesis concerning rats’ spatial working memory. This effect occurred when objects either differed visually (Experiments 1, 2, 4) or only by odor (Experiment 3). Rats performed no better than chance in finding a jackpot on their first choice from among three visually different objects in Experiments 1 and 2. Furthermore, results from Experiments 2 and 3 indicate that differences in the probability of finding a jackpot by chance in Experiment 1 were not responsible for failure to find the predicted inverse relationship. Results from Experiment 4 indicate that those from Experiments 2 and 3 were not solely due to size of test arrays. We discussed whether our findings could be attributed to innate foraging or perceptual isolation processes during testing or to perceptual encoding processes during exposure to study segment arrays.