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At least 919 records · Page 51Linked to original sources
PubMed1962

An adjusting avoidance schedule.

A shock-avoidance schedule is described in which the animal accumulated 5 sec of safe time whenever it pressed a lever. With this schedule, the animal was not differentially reinforced for long pauses between responses; and, consistent with this property of the schedule, the probability that the animal would press the lever was not related in any regular way to the amount of time that had elapsed since its preceding lever press. Other features of the performance are also described. If the animal was given a warning stimulus whenever it came within 5 sec of a shock, it tended to spend more time in the close temporal vicinity of the shock and less time at the maximum temporal distance from shock.

Adaptation, Psychological↗
PubMed1962

Observing responses in pigeons.

Pigeons were trained on an observing-response procedure in which periods of VR 100 and EXT alternated unpredictably during a white light (mixed stimulus). During VR 100, responses on a food-producing key (the first key) were intermittently reinforced. Responses on the observing key (the second key) produced a green light (positive stimulus) when VR 100 was in effect, and a red light (negative stimulus) for EXT. The birds did not respond on either key during the negative stimulus, but they responded on the food-producing key when the positive stimulus appeared. When observing responses produced the positive or negative stimulus on FR, observing responses were maintained until the FR reached a maximum; beyond this, only food-producing responses occurred. When observing responses did not produce either stimulus, the observing-response rates fell to zero. With prolonged exposure to an FR 20 schedule of observing, observing-response rates during EXT were higher than during VR 100. Chlorpromazine hydrochloride decreased the total response output but markedly increased observing-response rates except when it was administered before sessions of observing response extinction.

Animals↗
PubMed1998

Reinforcement without awareness: II. Word class.

In a previous study of reinforcement without awareness by Lieberman, Sunnucks, & Kirk (this issue), subjects were told that the experiment was on ESP; two words were presented on every trial, and their task was to choose the word the experimenter was thinking of. In fact, reinforcement was contingent on the loudness of the subjects' voices when responding. They found stronger evidence for reinforcement without awareness than in many previous studies, and they attributed their success in part to the reinforcement of a response to which subjects were unlikely to attend. To explore this factor further, we again used an ESP cover story but reinforced subjects for choosing the word in each pair that contained a double letter. We found evidence of reinforcement without awareness in three experiments and also identified two factors that influence these effects: Learning did not occur if subjects (a) were encouraged to test irrelevant hypotheses, or (b) sat in an uncomfortable chair. We speculate that learning without awareness may be more likely when subjects are relaxed and that hypothesis testing and uncomfortable chairs impair such learning because they prevent relaxation.

Adult↗
PubMed2006

High and low temperatures have unequal reinforcing properties in Drosophila spatial learning.

Small insects regulate their body temperature solely through behavior. Thus, sensing environmental temperature and implementing an appropriate behavioral strategy can be critical for survival. The fly Drosophila melanogaster prefers 24 degrees C, avoiding higher and lower temperatures when tested on a temperature gradient. Furthermore, temperatures above 24 degrees C have negative reinforcing properties. In contrast, we found that flies have a preference in operant learning experiments for a low-temperature-associated position rather than the 24 degrees C alternative in the heat-box. Two additional differences between high- and low-temperature reinforcement, i.e., temperatures above and below 24 degrees C, were found. Temperatures equally above and below 24 degrees C did not reinforce equally and only high temperatures supported increased memory performance with reversal conditioning. Finally, low- and high-temperature reinforced memories are similarly sensitive to two genetic mutations. Together these results indicate the qualitative meaning of temperatures below 24 degrees C depends on the dynamics of the temperatures encountered and that the reinforcing effects of these temperatures depend on at least some common genetic components. Conceptualizing these results using the Wolf-Heisenberg model of operant conditioning, we propose the maximum difference in experienced temperatures determines the magnitude of the reinforcement input to a conditioning circuit.

Adenylyl Cyclases↗
PubMed1984

Accuracy versus speed in the generalized effort of learning-disabled children.

Reinforcement of effortful performance in a given academic task has been found to increase the subsequent performance of other academic tasks. The learned-effort hypothesis assumes that individuals learn which dimensions of task performance are correlated with reinforcement of high effort, and generalize across tasks. Therefore, reinforcement of increased effort in a given dimension of one task should result in greater generalized effort in the same dimension of transfer performance than in another dimension. In accord with this view, preadolescent learning-disabled students who received points for high reading accuracy subsequently produced more accurate drawings and stories than did students whose points had been based upon high reading speed or upon mere completion of the reading task. Students who received points for high reading speed subsequently constructed stories more quickly than did children whose points had been based upon high reading accuracy or upon reading-task completion. Consistent with the more explicit and frequent feedback for accuracy than for speed in most academic tasks, generalized accuracy was much more durable than generalized speed.

Child↗
PubMedDate not supplied

Reinforcing communication skills while registered nurses simultaneously learn course content: a response to learning needs.

This article describes the implementation and evaluation of Integrated Skills Reinforcement (ISR) in a baccalaureate nursing course entitled "Principles of Health Assessment" for 15 registered nurse students. ISR is a comprehensive teaching-learning approach that simultaneously reinforces student writing, reading, speaking, and listening skills while they learn course content. The purpose of this study was to assess the influence of ISR on writing skills and student satisfaction. A learner's guide and teacher's guide, created in advance by the teacher, described specific language activities and assignments that were implemented throughout the ISR course. During each class, the teacher promoted discussion, collaboration, and co-inquiry among students, using course content as the vehicle of exchange. Writing was assessed at the beginning and end of the course. The influence of ISR on the content, organization, sentence structure, tone, and strength of position of student writing was analyzed. Writing samples were scored by an independent evaluator trained in methods of holistic scoring. Ninety-three per cent (14 of 15 students) achieved writing growth from .5 to 1.5 points on a scale of 6 points. Student response to both the ISR approach and specific ISR activities was assessed by teacher-created surveys administered at the middle-end of the course. One hundred per cent of the students at the end of this project agreed that the ISR activities, specifically the writing and reading activities, helped them better understand the course content. These responses differed from evaluations written by the same students at the middle of the course. The ISR approach fostered analysis and communication through active collaboration, behaviors cited as critical for effective participation of nurses in today's complex health care environment.

Adult↗
PubMed2001

Superordinate categorization via learned stimulus equivalence: quantity of reinforcement, hedonic value, and the nature of the mediator.

Three experiments examined superordinate categorization via stimulus equivalence training in pigeons. Experiment 1 established superordinate categories by association with a common number of food pellet reinforcers, plus it established generalization to novel photographic stimuli. Experiment 2 documented generalization of choice responding from stimuli signaling different numbers of food pellets to stimuli signaling different delays to food reinforcement. Experiment 3 indicated that different numbers of food pellets did not substitute as discriminative stimuli for the photographic stimuli with which the food pellets had been paired. The collective results suggest that the effective mediator of superordinate categories that are established via learned stimulus equivalence is not likely to be an accurate representation of the reinforcer, neither is it likely to be a distinctive response that is made to the discriminative stimulus. Motivational or emotional mediation is a more likely account.

Affect↗
PubMed1999

Spatial learning of an escape task by young corn snakes, Elaphe guttata guttata.

Spatial learning is critical to most animals for many behaviours necessary to survival. In vertebrates, most studies on spatial learning and memory have been conducted in mammalian and avian species with few studies on reptiles. We examined spatial learning in the corn snake, Elaphe guttata guttata by training 17 young snakes to find the one open shelter in an eight-hole arena, where the entrance was not visible from the arena surface. Over a 16-trial, 4-day training period, snakes showed (1) a significant decrease in the mean latency to the goal, (2) a significant decrease in the mean total distance travelled, (3) a significant increase in the percentage of the total distance travelled in the quadrant containing the goal, and (4) a significant increase in movement in the goal quadrant above chance. Although no differences were found in the number of errors made over the training period, snakes made fewer errors on all days than expected by chance. This study shows that snakes can learn rapidly a spatial-escape task that is relevant behaviourally and suggests that entering a shelter reinforces this learning. Mechanisms of orientation for the task described are discussed. Copyright 1999 The Association for the Study of Animal Behaviour.

Journal Article↗
PubMed1960

Control of vocal responding in chickens.

Schedules of reinforcement were shown to control the rate of chirping bychickens in the same way as other motor responses in subhumans. Under a discrimination procedure, chickens responded selectively to the visual stimulus associated with food reinforcement for chirping. Control experiments demonstrated that food influenced the rate of responding because it was presented dependent on the chick's vocalizing and not because it had an innate eliciting or "emotionalizing" power.

Animals↗
PubMed2003

Social influence in pigeons (Columba livia): the role of differential reinforcement.

Socially-influenced learning was studied in observer pigeons that observed a demonstrator in an adjacent chamber performing a target response comprising standing on a box and pecking a key 10 times. In Experiment 1 there was no evidence for social learning in the absence of reinforcement of the observer's behavior. When the target response was already established in the observer's repertoire, but was not differentially reinforced in relation to the demonstrator's behavior, rates of extinction were not influenced by the demonstrator's behavior (Experiment 2). Reinforcement of the observer's target response in the presence of the modeled target response, and not in its absence, resulted in control of the observer's responding by the behavior of the demonstrator (Experiments 3 and 4). This control was extended in Experiment 5 to deferred responses that occurred following a delay since the demonstrator's target responses. The acquisition of social influence depended on differential reinforcement of the observer's target response, with the demonstrator's target behavior serving as the explicit discriminative stimulus.

Animals↗
PubMed2003

Technology in the teaching of neuroscience: enhanced student learning.

The primary motivation for integrating any form of education technology into a particular course or curriculum should always be to enhance student learning. However, it can be difficult to determine which technologies will be the most appropriate and effective teaching tools. Through the alignment of technology-enhanced learning experiences with a clear set of learning objectives, teaching becomes more efficient and effective and learning is truly enhanced. In this article, I describe how I have made extensive use of technology in two neuroscience courses that differ in structure and content. Course websites function as resource centers and provide a forum for student interaction. PowerPoint presentations enhance formal lectures and provide an organized outline of presented material. Some lectures are also supplemented with interactive CD-ROMs, used in the presentation of difficult physiological concepts. In addition, a computer-based physiological recording system is used in laboratory sessions, improving the hands-on experience of group learning while reinforcing the concepts of the research method. Although technology can provide powerful teaching tools, the enhancement of the learning environment is still dependent on the instructor. It is the skill and enthusiasm of the instructor that determines whether technology will be used effectively.

CD-ROM↗
PubMed1974

On the role of the hippocampus in the integrative activity of the brain.

The present evidence plus data from the literature suggest that the hippocampus is concerned with responses to signals having low probability of reinforcement. The theta-rhythm, characteristic of the hippocampus, arises in a situation of pragmatic uncertainty, when stereotypical behavioral patterns have not yet been formed and when decisions are still being sought. The theta-rhythm may serve as a correlate only of orienting-exploratory responses and not as a correlate of the orienting-defensive responses of "biological alertness", in Pavlov's terminology. Functionally, the hippocampus belongs to the system of structures which make decisions about the response to a given stimulus. If, following destruction of the hippocampus, the neocortex gives preference to signals with high probability of reinforcement and in the sphere of unconditioned responses a stronger motivation is predominant, then hippocampal involvement is essential for simultaneous assessment of these two factors. For that reason, the hippocampus plays an important role in the competition among conditioned reflexes having different magnitudes and reinforcement probabilities.

Animals↗