Resistance to change of responding maintained by unsignaled delays to reinforcement: a response-bout analysis

Previous experiments have shown that unsignaled delayed reinforcement decreases response rates and resistance to change. However, the effects of different delays to reinforcement on underlying response structure have not been investigated in conjunction with tests of resistance to change. In the present experiment, pigeons responded on a three-component multiple variable-interval schedule for food presented immediately, following brief (0.5 s), or following long (3 s) unsignaled delays of reinforcement. Baseline response rates were lowest in the component with the longest delay; they were about equal with immediate and briefly delayed reinforcers. Resistance to disruption by presession feeding, response-independent food during the intercomponent interval, and extinction was slightly but consistently lower as delays increased. Because log survivor functions of interresponse times (IRTs) deviated from simple modes of bout initiations and within-bout responding, an IRT-cutoff method was used to examine underlying response structure. These analyses suggested that baseline rates of initiating bouts of responding decreased as scheduled delays increased, and within-bout response rates tended to be lower in the component with immediate reinforcers. The number of responses per bout was not reliably affected by reinforcer delay, but tended to be highest with brief delays when total response rates were higher in that component. Consistent with previous findings, resistance to change of overall response rate was highly correlated with resistance to change of bout-initiation rates but not with within-bout responding. These results suggest that unsignaled delays to reinforcement affect resistance to change through changes in the probability of initiating a response bout rather than through changes in the underlying response structure.     

Can't quite commit: rumination and uncertainty

Why do some individuals persist in self-destructive rumination? Two studies investigated the relation between a ruminative response style and the reluctance to initiate instrumental behavior. In Study 1, ruminators were compared to nonruminators regarding their evaluation of a self-generated plan to revise their university housing system and, in Study 2, concerning their plan to redesign the undergraduate curriculum. In both studies, on relevant composite measures, ruminators expressed less satisfaction and confidence with regard to their plans than did nonruminators. They were also less likely to commit to the plans they generated. The findings suggest that in addition to its documented detrimental effects on thinking and problem solving, self-focused rumination may inhibit instrumental behavior by increasing uncertainty, resulting in further rumination and behavioral paralysis.     

Synchronous neural oscillations and cognitive processes

The central problem for cognitive neuroscience is to describe how cognitive processes arise from brain processes. This review summarizes the recent evidence that synchronous neural oscillations reveal much about the origin and nature of cognitive processes such as memory, attention and consciousness. Memory processes are most closely related to theta and gamma rhythms, whereas attention seems closely associated with alpha and gamma rhythms. Conscious awareness may arise from synchronous neural oscillations occurring globally throughout the brain rather than from the locally synchronous oscillations that occur when a sensory area encodes a stimulus. These associations between the dynamics of the brain and cognitive processes indicate progress towards a unified theory of brain and cognition.     

Face recognition in pictures is affected by perspective transformation but not by the centre of projection

Recognition of unfamiliar faces is susceptible to image differences caused by angular sizes subtended from the face to the camera. Research on perception of cubes suggests that apparent distortions of a shape due to large camera angle are correctable by placing the observer at the centre of projection, especially when visibility of the picture surface is low (Yang and Kubovy, 1999 Perception & Psychophysics 61 456-467). To explore the implication of this finding for face perception, observers performed recognition and matching tasks where face images with reduced visibility of picture surface were shown with observers either at the centre of projection or at other viewpoints. The results show that, unlike perception of cubes, the effect of perspective transformation on face recognition is largely unaffected by the centre of projection. Furthermore, the use of perspective cues is not affected by textured surfaces. The limitation of perspective in restoring 3-D information of faces suggests a stronger role for image-based, rather than model-based, processes in recognition of unfamiliar faces.     

Serial position curves in short-term memory: functional equivalence across modalities

Four experiments investigated item and order memory for sequences of seen unfamiliar faces and heard nonwords. Experiments 1 and 3 found bowed serial position curves using the serial reconstruction test of order with faces and nonwords, respectively. Experiments 2 and 4 found limited recency, no primacy, and above chance performance on all items using a two-alternative forced choice (2AFC) test of item recognition, again with faces and nonwords. These results suggest that the different serial position curves typically found using traditional paradigms for exploring visual and verbal short-term memory are due to differences in the methods used rather than modality-specific mechanisms.     

Who Are the Next Generation of Genetic Counselors? A Survey of Students

Genetic counseling students were surveyed about their backgrounds, application process to genetic counseling programs, and career motivations and plans. Program directors from 27 accredited programs were asked to distribute 362 surveys to students. Fifty-two survey items assess demographics; sources of support for pursuing a genetic counseling career (information about genetic counseling, encouragement/discouragement from others); career motivations (reasons for applying and for becoming a genetic counselor); and career certainty. Two hundred and thirty-five usable surveys were returned (64.9% usable return rate). Most respondents were Caucasian females (mean age = 25.4 years). About 13% identified as ethnic minorities, and about one-third reported family histories of a genetic condition(s). Most respondents learned about the field in classes, and most were strongly encouraged by family and friends to pursue genetic counseling. Reasons rated as most important for becoming a genetic counselor included helping others and intellectual stimulation. Recruitment, training, and research recommendations are given.     

Innocence abroad: a pocket guide to psychological research on tourism

This article introduces tourism as a neglected topic of study for psychologists and discusses how ventures into this area provide opportunities for pioneering research and innovative applications. A coherent body of theory, drawn from experimental, social, and health psychology and synthesized by cross-cultural psychologists for the study of acculturation, is presented as one foundation for this area of inquiry. This includes stress and coping, culture learning, and social identification theories. The conceptual frameworks are applied to the interpretation of selected studies of tourism and are recommended for designing prospective investigations and guiding future research.     

Effects of posting self-set goals on collegiate football players' skill execution during practice and games

The effects of self-set goals and public posting on athletic performance of 5 collegiate football players was studied. All players were linebackers on a National Association of Intercollegiate Athletics Division II football team. The dependent variables were the percentage of correct occasions when the linebacker (a) positioned himself to cover a specified area on the field during a pass or from the line of scrimmage during a run; (b) moved to the correct position in response to the positioning of the offense; and (c) tackled and stopped the progress of the ball carrier. A multiple baseline design across behaviors showed an immediate increase in the practice performance of the players and a corresponding increase in game performance following introduction of the independent variable. This study extends research using public posting in sport by demonstrating the effects of player-determined goals and public posting of goal attainment.