ethanporcaro/eric-fulltext-meta huggingface dataset:
Pigeons' Discounting of Probabilistic and Delayed Reinforcers
Author: Green, Leonard
Date: 2010-09-00
Type: Journal Articles
Subjects: Reinforcement,Probability,Animal Behavior,Food,Delay of Gratification,Cues,Light,Color,Behavioral Science Research

Pigeons' discounting of probabilistic and delayed food reinforcers was studied using adjusting-amount procedures. In the probability discounting conditions, pigeons chose between an adjusting number of food pellets contingent on a single key peck and a larger, fixed number of pellets contingent on completion of a variable-ratio schedule. In the delay discounting conditions, pigeons chose between an adjusting number of pellets delivered immediately and a larger, fixed number of pellets delivered after a delay. Probability discounting (i.e., subjective value as a function of the odds against reinforcement) was as well described by a hyperboloid function as was delay discounting (i.e., subjective value as a function of the time until reinforcement). As in humans, the exponents of the hyperboloid function when it was fitted to the probability discounting data were lower than the exponents of the hyperboloid function when it was fitted to the delay discounting data. The subjective values of probabilistic reinforcers were strongly correlated with predictions based on simply substituting the average delay to their receipt in each probabilistic reinforcement condition into the hyperboloid discounting function. However, the subjective values were systematically underestimated using this approach. Using the discounting function proposed by Mazur (1989), which takes into account the variability in the delay to the probabilistic reinforcers, the accuracy with which their subjective values could be predicted was increased. Taken together, the present findings are consistent with Rachlin's (Rachlin, 1990; Rachlin, Logue, Gibbon, & Frankel, 1986) hypothesis that choice involving repeated gambles may be interpreted in terms of the delays to the probabilistic reinforcers. (Contains 4 figures and 1 table.)
Factors Impacting Emergence of Behavioral Control by Underselected Stimuli in Humans after Reduction of Control by Overselected Stimuli
Author: Broomfield, Laura
Date: 2010-09-00
Type: Journal Articles
Subjects: Visual Stimuli,Discrimination Learning,Environmental Influences,Adults,Novelty (Stimulus Dimension),College Students,Psychology,Feedback (Response),Behavioral Science Research,Pervasive Developmental Disorders

Stimulus overselectivity occurs when only one of potentially many aspects of the environment controls behavior. Adult participants were trained and tested on a trial-and-error discrimination learning task while engaging in a concurrent load task, and overselectivity emerged. When responding to the overselected stimulus was reduced by reinforcing a novel stimulus in the presence of the previously overselected stimulus in a second trial-and-error discrimination task, behavioral control by the underselected stimulus became stronger. However, this result was only found under certain circumstances: when there was substantial overselectivity in the first training phase; when control by the underselected stimulus in the first phase was particularly low; and when there was effective reduction in the behavioral control exerted by the previously overselected stimuli. The emergence of behavioral control by the underselected stimulus suggests that overselectivity is not simply due to an attention deficit, because for the emergence to occur, the stimuli must have been attended to and learned about in the training phase; but that a range of additional learning factors may play a role. (Contains 5 figures.)
Exclusive Preference Develops Less Readily on Concurrent Ratio Schedules with Wheel-Running than with Sucrose Reinforcement
Author: Belke, Terry W.
Date: 2010-09-00
Type: Journal Articles
Subjects: Reinforcement,Animals,Physical Activities,Food,Time,Reaction Time

Previous research suggested that allocation of responses on concurrent schedules of wheel-running reinforcement was less sensitive to schedule differences than typically observed with more conventional reinforcers. To assess this possibility, 16 female Long Evans rats were exposed to concurrent FR FR schedules of reinforcement and the schedule value on one alternative was systematically increased. In one condition, the reinforcer on both alternatives was 0.1 ml of 7.5% sucrose solution; in the other, it was a 30-s opportunity to run in a wheel. Results showed that the average ratio at which greater than 90% of responses were allocated to the unchanged alternative was higher with wheel-running reinforcement. As the ratio requirement was initially increased, responding strongly shifted toward the unchanged alternative with sucrose, but not with wheel running. Instead, responding initially increased on both alternatives, then subsequently shifted toward the unchanged alternative. Furthermore, changeover responses as a percentage of total responses decreased with sucrose, but not wheel-running reinforcement. Finally, for some animals, responding on the increasing ratio alternative decreased as the ratio requirement increased, but then stopped and did not decline with further increments. The implications of these results for theories of choice are discussed. (Contains 10 figures and 1 table.)
Dynamics of Choice: A Tutorial
Author: Baum, William M.
Date: 2010-09-00
Type: Journal Articles
Subjects: Behavioral Science Research,Animals,Animal Behavior,Time,Feedback (Response),Systems Approach

Choice may be defined as the allocation of behavior among activities. Since all activities take up time, choice is conveniently thought of as the allocation of time among activities, even if activities like pecking are most easily measured by counting. Since dynamics refers to change through time, the dynamics of choice refers to change of allocation through time. In the dynamics of choice, as in other dynamical systems that include feedback, change is away from perturbation and toward a steady state. Steady state or equilibrium is assessed on a longer time scale than change because change is only visible on a smaller time scale. When we compare laws of equilibrium, such as the matching law with laws of dynamics, two possibilities emerge. "Self-similarity" occurs when the same law can be seen across smaller time scales, with the result that the law at longer time scales may be understood as the expression of its application at smaller time scales. "Reduction" occurs when the dynamics at a small time scale are incommensurate with the dynamics at longer time scales. Then the process at the longer time scale is reduced to a qualitatively different process at the smaller time scale, as when choice is reduced to switching patterns. When reduction occurs, the dynamics at the longer time scale may be derived from the process at the smaller time scale, but not the other way around. Research at different time scales is facilitated by the molar view of behavior. (Contains 16 figures and 1 table.)
Development and Maintenance of Choice in a Dynamic Environment
Author: Rodewald, Andrew M.
Date: 2010-09-00
Type: Journal Articles
Subjects: Behavioral Science Research,Animals,Animal Behavior,Reinforcement,Replication (Evaluation)

Four pigeons were exposed to a concurrent procedure similar to that used by Davison, Baum, and colleagues (e.g., Davison & Baum, 2000, 2006) in which seven components were arranged in a mixed schedule, and each programmed a different left:right reinforcer ratio (1:27, 1:9, 1:3, 1:1, 3:1, 9:1, 27:1). Components within each session were presented randomly, lasted for 10 reinforcers each, and were separated by 10-s blackouts. These conditions were in effect for 100 sessions. When data were aggregated over Sessions 16-50, the present results were similar to those reported by Davison, Baum, and colleagues: (a) preference adjusted rapidly (i.e., sensitivity to reinforcement increased) within components; (b) preference for a given alternative increased with successive reinforcers delivered via that alternative ("continuations"), but was substantially attenuated following a reinforcer on the other alternative (a "discontinuation"); and (c) food deliveries produced "preference pulses" (immediate, local, increases in preference for the just-reinforced alternative). The same analyses were conducted across 10 session blocks for sessions 1-100. In general, the basic structure of choice revealed by analyses of data from Sessions 16-50 was preserved at a smaller level of aggregation (10 sessions), and it developed rapidly (within the first 10 sessions). Some characteristics of choice, however, changed systematically across sessions. For example, effects of successive reinforcers within a component tended to increase across sessions, as did the magnitude and length of the preference pulses. Thus, models of choice under these conditions may need to take into account variations in behavior allocation that are not captured completely when data are aggregated over large numbers of sessions. (Contains 14 figures.)
The Effects of a Local Negative Feedback Function between Choice and Relative Reinforcer Rate
Author: Davison, Michael
Date: 2010-09-00
Type: Journal Articles
Subjects: Behavioral Science Research,Animals,Animal Behavior,Reinforcement,Behavior Modification,Feedback (Response),Responses,Intervals,Probability

Four pigeons were trained on two-key concurrent variable-interval schedules with no changeover delay. In Phase 1, relative reinforcers on the two alternatives were varied over five conditions from 0.1 to 0.9. In Phases 2 and 3, we instituted a molar feedback function between relative choice in an interreinforcer interval and the probability of reinforcers on the two keys ending the next interreinforcer interval. The feedback function was linear, and was negatively sloped so that more extreme choice in an interreinforcer interval made it more likely that a reinforcer would be available on the other key at the end of the next interval. The slope of the feedback function was -1 in Phase 2 and -3 in Phase 3. We varied relative reinforcers in each of these phases by changing the intercept of the feedback function. Little effect of the feedback functions was discernible at the local (interreinforcer interval) level, but choice measured at an extended level across sessions was strongly and significantly decreased by increasing the negative slope of the feedback function. (Contains 1 table and 6 figures.)
Rapid Acquisition of Choice and Timing and the Provenance of the Terminal-Link Effect
Author: Kyonka, Elizabeth G. E.
Date: 2010-09-00
Type: Journal Articles
Subjects: Behavioral Science Research,Animals,Animal Behavior,Reinforcement,Intervals

Eight pigeons responded in a concurrent-chains procedure in which terminal-link schedules changed pseudorandomly across sessions. Pairs of terminal-link delays either summed to 15 s or to 45 s. Across sessions, the location of the shorter terminal link changed according to a pseudorandom binary sequence. On some terminal links, food was withheld to obtain start and stop times, measures of temporal control. Log initial-link response ratios stabilized within the first half of each session. Log response ratio was a monotonically-increasing but nonlinear function of programmed log terminal-link immediacy ratio. There was an effect of absolute terminal-link duration on log response ratio: For most subjects, preference for the relatively shorter terminal-link delay was stronger when absolute delays were long than when absolute delays were short. Polynomial regressions and model comparison showed that differences in degree of nonlinearity, not in sensitivity to log immediacy ratio, produced this effect. Temporal control of stop times was timescale invariant with scalar variability, but temporal control of start times was not consistent across subjects or terminal-link durations. (Contains 7 figures, 4 tables and 1 footnote.)
A Decision Model for Steady-State Choice in Concurrent Chains
Author: Christensen, Darren R.
Date: 2010-09-00
Type: Journal Articles
Subjects: Selection,Decision Making,Models,Conditioning,Reinforcement,Animals

Grace and McLean (2006) proposed a decision model for acquisition of choice in concurrent chains which assumes that after reinforcement in a terminal link, subjects make a discrimination whether the preceding reinforcer delay was short or long relative to a criterion. Their model was subsequently extended by Christensen and Grace (2008, 2009a, 2009b) to include effects of initial- and terminal-link duration on choice. We show that an expression for steady-state responding can be derived from the decision model, which enables a model for choice that provides an account of archival data that is equal or superior to the contextual choice model (Grace, 1994) and hyperbolic value-added model (Mazur, 2001) in terms of goodness of fit, parsimony, and parameter invariance. The success of the steady-state decision model validates the strategy of understanding acquisition phenomena as a bridge toward explaining choice at the molar level. (Contains 2 tables, 2 figures and 2 footnotes.)
Toward a Mechanics of Adaptive Behavior: Evolutionary Dynamics and Matching Theory Statics
Author: McDowell, J. J.
Date: 2010-09-00
Type: Journal Articles
Subjects: Adjustment (to Environment),Behavior Theories,Evolution,Reinforcement

One theory of behavior dynamics instantiates the idea that behavior evolves in response to selection pressure from the environment in the form of reinforcement. This computational theory implements Darwinian principles of selection, reproduction, and mutation, which operate on a population of potential behaviors by means of a genetic algorithm. The behavior of virtual organisms animated by this theory may be studied in any experimental environment. The evolutionary theory was tested by comparing the steady-state behavior it generated on concurrent schedules to the description of steady state behavior provided by modern matching theory. Ensemble fits of modern matching theory that enforced its constant-k requirement and the parametric identities required by its equations, accounted for large proportions of data variance, left random residuals, and yielded parameter estimates with values and properties similar to those obtained in experiments with live organisms. These results indicate that the dynamics of the evolutionary theory and the statics of modern matching theory together constitute a good candidate for a mechanics of adaptive behavior. (Contains 8 figures and 3 tables.)
The Dynamics of Successive Induction in Larval Zebrafish
Author: Staddon, J. E. R.
Date: 2010-09-00
Type: Journal Articles
Subjects: Behavior Patterns,Behavioral Science Research,Responses,Animals,Motion,Light,Neurological Organization,Physiology

Charles Sherrington identified the properties of the synapse by purely behavioral means--the study of reflexes--more than 100 years ago. They were subsequently confirmed neurophysiologically. Studying reflex interaction, he also showed that activating one reflex often facilitates another, antagonistic one: "successive induction," which has since been demonstrated in a wide range of species, from aphids to grasshoppers to dogs and humans. We show a particularly orderly example in zebrafish ("Danio rerio") larvae; the behavior (locomotion) of larvae is low in dark and intermediate in light, but low in light and substantially higher in dark when dark followed light. A quantitative model of a simple dynamic process is described that readily captures the behavior pattern and the effects of a number of manipulations of lighting conditions. (Contains 7 figures and 1 footnote.)
Patterns of Stress, Coping Styles and Social Supports among Adolescents
Author: Latha, K. S.
Date: 2007-00-00
Type: Journal Articles
Subjects: Adolescents,Coping,Interviews,Social Networks,Social Support Groups,Secondary School Students,Measures (Individuals),Income,Study Habits,Time on Task,Sleep,Religion,Gender Differences,Stress Variables

Introduction: This study aimed to assess the nature of stress, social support systems and coping styles among adolescents. Methods: 100 students in Pre University College (II year) of both genders in the age range of 16-19 years were assessed with the Adolescent Stress Scale, a semi-structured interview to elicit social support, and a self-report coping scale. Results: The main sources of stress in both genders were getting up early in the morning, pressure to study, having to concentrate for too long during college hours, not having enough money to buy things, and long college hours. Prayer was the main coping strategy used by both genders. Males had larger social network than females. Conclusions: Schools/colleges should provide opportunities to work through the stresses related to college and studies by instituting specialized programmes. (Contains 2 tables.)
Relationship between Test Anxiety and Parenting Style
Author: Thergaonkar, Neerja R.
Date: 2007-00-00
Type: Journal Articles
Subjects: Parenting Styles,Child Rearing,Test Anxiety,Parent Child Relationship,Prevention,Correlation,Parent Attitudes,Academic Achievement,Gender Differences,Stereotypes,Parent Aspiration,Mothers,Democratic Values,Indians,Foreign Countries,Measures (Individuals)

Introduction: The aim of the present study was to explore the relationship between test anxiety and parenting style. Method: Democratic attitude of parents, acceptance of parents by the child, parental attitude regarding academics, parental expectations and gender stereotyped perceptions of parents regarding academics were evaluated in the domain of parenting style in a convenience sample of 207 students and 200 mothers. Results: A statistically significant negative correlation was observed between test anxiety and democratic attitude of parents and acceptance of parents by the child. Conclusion: Inculcating a democratic style of parenting and greater acceptance of parents among children may prevent or ameliorate test anxiety. (Contains 1 table.)
Suicides in Adolescents: Benefit/Harm Balance of Antidepressants
Author: Saz, Ulas Eylem
Date: 2007-00-00
Type: Journal Articles
Subjects: Suicide,Adolescents,Foreign Countries,Depression (Psychology),Drug Therapy,Risk,Hospitals,Role,Research Needs

Introduction: Depression is an important cause of suicide in adolescents. It has been speculated that antidepressants themselves can increase the risk of suicide. Method: Cases of adolescents admitted to the Ege University Pediatric Emergency Department in Turkey due to suicide attempt were assessed. Results: Nine of 13 suicide attempts during June 2005 were due to overdose of antidepressants prescribed for major depressive disorder. Conclusion: Well-designed studies are needed to elucidate the role of antidepressant drugs in suicide. (Contains 1 table.)
Characteristics of Patients Visiting the Child &amp; Adolescent Psychiatric Clinic: A 26-Year Study from North India
Author: Malhotra, Savita
Date: 2007-00-00
Type: Journal Articles
Subjects: Psychiatric Services,Age,Epilepsy,Mental Retardation,Behavior Disorders,Psychiatry,Identification,Patients,Foreign Countries,Brain,Profiles,Children,Adolescents,Neurosis,Neurological Impairments,Clinical Diagnosis,Stress Variables,Psychosis,Hospitals

Aim: To study the sociodemographic and clinical profile of patients, who presented to the child and adolescent psychiatric services of a tertiary care centre over a 26-year period (1980-2005). Methodology: Data were abstracted retrospectively from detailed work up files of all subjects assessed in the Child and Adolescent Psychiatry (CAP) Clinic during the mentioned period. Time trends were examined over 3-periods: 1980-1989 (Period I), 1990-1999 (Period II) and 2000-2005 (Period III). Results: Most of the individuals presenting to CAP clinic were boys (62.2%-63.5%), aged between 10 to 15 years (44.2%-63.4%). The common diagnoses were mental retardation (18.4%-33.2%), neurotic and stress related disorders (16.4%-18.5%), epilepsy and organic brain disorder (7.1%-15.1 %) and hyperkinetic and conduct disorders (8.3%-17.9%). There was a trend towards decrease in number of cases in younger age group (0-5 years) and those with diagnosis of mental retardation, epilepsy and organic brain disorder. There was a trend towards increase in number of cases in the older age group (10-15 years) and those with diagnosis of psychotic disorders, affective disorders, disorders of psychological development, and hyperkinetic and conduct disorders. Conclusion: Time trends reveal significant shifts in demographic and diagnostic profile of a CAP clinic of a tertiary care hospital. (Contains 3 tables.)
Adolescent Self-Esteem, Attachment and Loneliness
Author: Dhal, Anubha
Date: 2007-00-00
Type: Journal Articles
Subjects: Public Schools,Attachment Behavior,Adolescents,Measures (Individuals),Psychological Patterns,Self Esteem,Gender Differences,Foreign Countries,Parent Child Relationship,Intervention,Indians

Objectives: To assess self-esteem, loneliness and attachment styles among adolescents and examine their association with each other and with age and gender. Method: Adolescents (55 males and 55 females) from a public school in Delhi, aged 10-13 years were administered Coopersmith Self-Esteem Inventory (School Form), Attachment Scale and UCLA Loneliness Scale. Results: Adolescents aged 10-11 years reported higher self-esteem as compared to those aged 12-13 years (p less than 0.01). Low global, general and home-parents self-esteem were associated with high levels of loneliness. Adolescents with high self-esteem were securely attached while those with low self-esteem had preoccupied and fearful attachment. Conclusions: Adolescents studying in a public school reported high levels of self-esteem, moderate loneliness and a secure attachment style. Students with low self-esteem and feelings of loneliness may benefit from psychological intervention.
Validity of Classification of Externalizing Disorders
Author: Sengupta, Somnath
Date: 2007-00-00
Type: Journal Articles
Subjects: Public Health,Validity,Behavior Disorders,Classification,Children,Clinical Diagnosis,Symptoms (Individual Disorders),Attention Deficit Disorders,Attention Deficit Hyperactivity Disorder

There is increasing recognition that the externalizing disorders continue into adulthood or cause substantial impairment that may persist into adulthood. These disorders place substantial demands on the health care, education and legal resources and have considerable public health importance. The concept and the nosology of the externalizing disorders have evolved considerably over the last few decades. Efforts were made to keep DSM-IV (Diagnostic and Statistical Manual) and ICD-10 (International Classification of Diseases) close to each other to enhance international consensus and subsequently the validity of these disorders. This article aims to review the conceptual basis and the debate over the nosology of externalizing disorders with a view to examine the validity of ICD-10 diagnoses.