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PubMed2001

No more tours: how library tours of the past become today's celebrations.

In 1999, Northwestern University's Galter Health Sciences Library redesigned the library orientation program for first-year medical students. Surveys indicated tours were ineffective and students retained little of the information presented. Furthermore, the tour was not related to the student's curriculum and did not reinforce their learning objectives. As a replacement, the library staff developed a self-directed two-hour library open house. Stations throughout the library showcased the library staff, services, and resources, focusing on the first-year student curriculum. A follow-up survey found this redesign more useful and relevant to the students' course work, indicating libraries should be creating more interactive tours for students allowing them to learn actively.

Chicago↗
PubMed1979

Self-control training in the classroom: a review and critique.

Self-control training in classroom settings is becoming widespread. Establishing effective self- rather than externally controlled behavior modification programs in schools would enable children to control their own academic and social behavior, while enabling teachers to devote more time to teaching. The following components of self-control are reviewed in the present article: self-recording, self-evaluation, self-determination of contingencies, and self-instruction. Self-control strategies designed for the maintenance of appropriate classroom behavior, and issues associated with self-control training, such as the reliability of self-observation, response maintenance, generalization, and the role of external control, are examined. Finally, suggestions for maximizing the potential effectiveness of self-control training in the classroom (e.g., teaching self-observational procedures, teaching students to provide themselves with instructions and praise), as well as future areas for experimental investigation (e.g., social changes that may be associated with self-control procedures), are presented.

Adolescent↗
PubMed1962

Complex response patterns during temporally spaced responding.

A series of experiments is reported in which two monkeys emitted complex response patterns, not specified by the experimental program, during the DRL component of a multiple schedule. Administration of sodium pentobarbital and dl-amphetamine, drugs which disrupted the DRL performance, were also observed to suppress these collateral responses. Sequences of these collateral responses appear to mediate, at least in part, the timing process required for reinforced performance on the DRL schedule.

Amphetamine↗
PubMed1962

Laboratory control of thumbsucking by withdrawal and re-presentation of reinforcement.

A 5-year-old boy was shown cartoons, and punished for thumbsucking during alternate cartoons by turning off the cartoons for as long as his thumb remained in his mouth. Thumbsucking weakened during such periods. During alternate periods of uninterrupted cartoons, thumbsucking promptly recovered, suggesting a quick discrimination process. Two other 5-year-old boys were shown the same cartoons; withdrawal of the cartoons was made contingent upon thumbsucking for one, and randomly yoked for the other. Then their roles were reversed. Contingent withdrawal and re-presentation of the cartoons controlled thumbsucking rate; yoked withdrawal and re-presentation did not.

Face↗
PubMed1963

Punishment of temporally spaced responding.

The responses of pigeons were maintained by a DRL schedule of food reinforcement. With this schedule, responses were reinforced only when a fixed period of time elapsed without an intervening response. Punishment of all responses reduced the frequency of these responses as a direct function of the punishment intensity. As a consequence of the increased temporal spacing of responses, more reinforcements resulted during punishment. Under progressively higher intensities of punishment, the reinforcement frequency increased to a maximum value and then decreased at the highest intensities. The increased frequency of reinforcement which resulted during punishment did not counteract the suppressive effect of punishment, nor did it lead to a low response rate after punishment was removed. Punishment did not reduce the inter-response time distribution uniformly, but rather especially reduced the number of short inter-response times. Even at the low punishment intensities, the number of short inter-response times was considerably reduced. After punishment was discontinued, performance recovered almost completely after a compensatory burst. The number as well as the temporal pattern of responses returned to normal.

Animals↗
PubMed1963

Fixed-ratio punishment.

Responses were maintained by a variable-interval schedule of food reinforcement. At the same time, punishment was delivered following every nth response (fixed-ratio punishment). The introduction of fixed-ratio punishment produced an initial phase during which the emission of responses was positively accelerated between punishments. Eventually, the degree of positive acceleration was reduced and a uniform but reduced rate of responding emerged. Large changes in the over-all level of responding were produced by the intensity of punishment, the value of the punishment ratio, and the level of food deprivation. The uniformity of response rate between punishments was invariant in spite of these changes in over-all rate and contrary to some plausible a priori theoretical considerations. Fixed-ratio punishment also produced phenomena previously observed under continuous punishment: warm-up effect and a compensatory increase. This type of intermittent punishment produced less rapid and less complete suppression than did continuous punishment.

Punishment↗
PubMed1963

Effects of hunger and VI value on VI pacing.

In two experiments, each involving four rats, responses preceded by an inter-response time between 8 and 10 sec in duration were intermittently reinforced. In Experiment I, final performance was compared under two hunger levels, while the frequency of reinforcement was held constant by a VI 5 schedule. In Experiment II, hunger was held constant and VI 3 was compared with VI 8. Both hunger and frequency of reinforcement increased the over-all rate of response, but the exact effects of these operations on temporal discrimination were different for different rats. Usually, a peak "response probability" (IRTs/Op ratio) was obtained 8 to 10 sec after the preceding response, indicating adaptation to the reinforcement contingency, but in some cases this peak was about 2 sec earlier. One rat exhibited unusually pronounced bursting which seemed to alternate with adaptive temporally spaced responding. Prolonged pauses, observable in the cumulative records, particularly following reinforcement, were attributed to the fact that inter-response times greater than 10 sec were not reinforced, so that as the interval of time since the preceding response became discriminably greater than 10 sec, the probability of a response became small.

Animals↗
PubMed1963

d-Amphetamine-chlorpromazine antagonism in a food reinforced operant.

Dose effect curves for d-amphetamine and chlorpromazine were obtained with rats on a milk reinforced FR 10 schedule. A dose of d-amphetamine (2.5 mg/kg, i.p.) which completely suppressed all responding for 60 min was administered simultaneously (concomitant with the pretreatment times) with various doses of chlorpromazine. The d-amphetamine-induced cessation of responding was removed by several of the doses of chlorpromazine with maximal antagonism occurring at a dose of 1.5 mg/kg i.p. This dose of chlorpromazine, when administered independently, produced no observable side effects and showed no effect on the FR 10 schedule. One animal appeared to develop tolerance to the repeated dosages of d-amphetamine.

Animals↗
PubMed1982

Responses and pauses: discrimination and a choice catastrophe.

Pigeons produced a stimulus change either by responding or by not responding for a specified time period (by pausing). They then had to choose between two responses to obtain food. One choice was correct if the first component had been completed by a response; the other was correct if the component had been completed by a pause. The pigeons usually chose correctly, thereby indicating that they used their own prior behavior as a discriminative stimulus. Fixed pause requirements did not produce equal first component completions by a response and by a pause. To obtain equality, the pause requirement was titrated as a function of current performance. Titration resulted in equal completions and also produced accurate discrimination. In addition to showing that pigeons discriminated whether they had responded or paused, the data displayed and discontinuous functions predicted by catastrophe theory. Another procedure used forced choice rather than titration to produce equal completions by pausing and responding and also showed accurate discrimination of behavior.

Animals↗
PubMed1986

Auditory word discriminations in the pigeon.

Four pigeons were trained on a multiple variable-interval 30-s extinction schedule with various pairs of spoken English words presented as the discriminative stimuli. The birds typically produced discrimination indices of 70% to 90% accuracy. Discrimination accuracy was improved by shortening the interval between auditory stimulus presentations, and by increasing the number of syllables in the words.

Animals↗
PubMed1991

Subjective probability and delay.

Human subjects indicated their preference between a hypothetical $1,000 reward available with various probabilities or delays and a certain reward of variable amount available immediately. The function relating the amount of the certain-immediate reward subjectively equivalent to the delayed $1,000 reward had the same general shape (hyperbolic) as the function found by Mazur (1987) to describe pigeons' delay discounting. The function relating the certain-immediate amount of money subjectively equivalent to the probabilistic $1,000 reward was also hyperbolic, provided that the stated probability was transformed to odds against winning. In a second experiment, when human subjects chose between a delayed $1,000 reward and a probabilistic $1,000 reward, delay was proportional to the same odds-against transformation of the probability to which it was subjectively equivalent.

Adult↗
PubMed2006

Rapid acquisition in concurrent chains: evidence for a decision model.

Pigeons' choice in concurrent chains can adapt to rapidly changing contingencies. Grace, Bragason, and McLean (2003) found that relative initial-link response rate was sensitive to the immediacy ratio in the current session when one of the terminal-link fixed-interval schedules was changed daily according to a pseudorandom binary sequence (e.g., Schofield & Davison, 1997). The present experiment tested whether the degree of variation in delays across sessions had any effect on acquisition rate in Grace et al.'s (2003) rapid-acquisition procedure. In one condition ("minimal variation"), the left terminal link was always fixed-interval 8 s and the right terminal link was either fixed-interval 4 s or fixed-interval 16 s. In the other condition ("maximal variation"), a unique pair of fixed-interval values was used in each session. Responding was sensitive to the current-session immediacy ratio in both conditions, but across subjects there was no systematic difference in sensitivity. These results challenge the view that initial-link responding in the rapid-acquisition procedure is determined by changes in the learned value of the terminal-link stimuli, and suggests instead that a process resembling categorical discrimination may control performance. A decision model based on the assumption that delays are categorized as short or long relative to the history of delays provided a good account of the data and shows promise in being able to explain other choice phenomena.

Animals↗
PubMed2003

The mind through chick eyes: memory, cognition and anticipation.

To understand the animal mind, we have to reconstruct how animals recognize the external world through their own eyes. For the reconstruction to be realistic, explanations must be made both in their proximate causes (brain mechanisms) as well as ultimate causes (evolutionary backgrounds). Here, we review recent advances in the behavioral, psychological, and system-neuroscience studies accomplished using the domestic chick as subjects. Diverse behavioral paradigms are compared (such as filial imprinting, sexual imprinting, one-trial passive avoidance learning, and reinforcement operant conditioning) in their behavioral characterizations (development, sensory and motor aspects of functions, fitness gains) and relevant brain mechanisms. We will stress that common brain regions are shared by these distinct paradigms, particularly those in the ventral telencephalic structures such as AIv (in the archistriatum) and LPO (in the medial striatum). Neuronal ensembles in these regions could code the chick's anticipation for forthcoming events, particularly the quality/quantity and the temporal proximity of rewards. Without the internal representation of the anticipated proximity in LPO, behavioral tolerance will be lost, and the chick makes impulsive choice for a less optimized option. Functional roles of these regions proved compatible with their anatomical counterparts in the mammalian brain, thus suggesting that the neural systems linking between the memorized past and the anticipated future have remained highly conservative through the evolution of the amniotic vertebrates during the last 300 million years. With the conservative nature in mind, research efforts should be oriented toward a unifying theory, which could explain behavioral deviations from optimized foraging, such as "naïve curiosity," "contra-freeloading," "Concorde fallacy," and "altruism."

Animals↗
PubMed2026

User Engagement and Feature Preferences in an AI-Powered mHealth Intervention for Diabetes Prevention: Secondary Analysis of a Randomized Controlled Trial.

BACKGROUND: Prediabetes is highly prevalent and increasing globally, yet lifestyle interventions remain underused. AI-driven mobile health (mHealth) tools can help scale diabetes prevention efforts, but the key factors driving their success are not well understood. OBJECTIVE: This post hoc secondary analysis of a randomized controlled trial (RCT) aimed to characterize the most valued features and the role of user engagement in outcomes of a fully automated mHealth intervention for diabetes prevention. METHODS: Data from 151 participants with prediabetes and overweight or obesity who were assigned to an AI-based diabetes prevention program (Sweetch) in a parent RCT (NCT05056376) were analyzed. Engagement (defined as the total number of days the app was used) was categorized into tertiles (low, medium, and high). Baseline characteristics were compared across engagement groups using ANOVA, Kruskal-Wallis, and chi-square tests, and regression models assessed the association between engagement and achievement of diabetes risk reduction outcomes (&#x2265;5% weight loss, &#x2265;4% weight loss with &#x2265;150 min/week of physical activity, or &#x2265;0.2 percentage point reduction in hemoglobin A1c [HbA1c] at 12 months). Perceived usefulness of intervention features was surveyed at 12 months. RESULTS: Median engagement was 98 (IQR 34-232) days. Older age (P<.001) and lower baseline BMI (P=.04) were significantly associated with higher engagement. Compared with low engagement, high engagement was associated with greater odds of achieving the composite diabetes risk reduction outcome (odds ratio [OR] 2.59, 95% CI 1.11-6.01; P=.03), &#x2265;5% weight loss (OR 3.31, 95% CI 1.16-9.42; P=.03), and &#x2265;0.2 percentage point reduction in HbA1c (OR 3.57, 95% CI 1.19-10.75; P=.02). Participants most frequently rated weight tracking, physical activity tracking, and the digital body weight scale as the features that were most helpful for achieving their health goals. CONCLUSIONS: Higher engagement with an AI-driven intervention requiring no human intervention was associated with improved diabetes risk reduction. Contrary to concerns about lower digital literacy, older adults engaged with the intervention more than younger adults. Features related to weight and physical activity tracking were most valued by patients in the program. TRIAL REGISTRATION: ClinicalTrials.gov NCT05056376; https://clinicaltrials.gov/study/NCT05056376.

Humans↗
PubMed2004

Philippine academic visit: brief but life-changing.

As one way of inculcating international perspectives in its graduates, the University of South Australia includes in its programs various opportunities for students to study abroad. It also encourages incoming short-term exchange and full-program international students. In 2001, the Discipline of Nursing and Rural Health (Whyalla Campus) sent two graduating students to a developing country in Asia, the Philippines, for a twelve-week academic experience. Despite problems causing the visit to be curtailed, much was learned. Participant and organiser insights are described, sharing valuable lessons to inform future plans and ensure better results. What could be regarded as a failed academic visit, nevertheless offered a life-changing opportunity and significant learning outcomes, reinforcing the belief that international academic experiences are extremely worthwhile for students and participating institutions. These experiences provide an important path to cultural understandings, and to personal and professional development.

Australia↗