Pretraining and discrimination reversal learning by rhesus monkeys

Groups of five to seven macaques were trained on repeated reversals of a visual (or spatial) discrimination habit after no pretraining, extended discrimination training, or repeated reversal training on spatial (or visual) cues. Neither sort of pretraining had a significant effect on reversal learning on the second cue. These results indicate that monkeys’ capacity to develop generalized “win-stay, lose-shift” hypotheses may have been exaggerated in previous experiments.     

Effect of age on discrimination learning,reversal learning,and cognitive bias in family dogs

Several studies on age-related cognitive decline in dogs involve laboratory dogs and prolonged training. We developed two spatial tasks that required a single 1-h session. We tested 107 medium-large sized dogs: “young” (N=41, aged 2.5–6.5 years) and “old” (N=66, aged 8–14.5 years). Our results indicated that, in a discrimination learning task and in a reversal learning task, young dogs learned significantly faster than the old dogs, indicating that these two tasks could successfully be used to investigate differences in spatial learning between young and old dogs. We also provide two novel findings. First, in the reversal learning, the dogs trained based on the location of stimuli learned faster than the dogs trained based on stimulus characteristics. Most old dogs did not learn the task within our cut-off of 50 trials. Training based on an object’s location is therefore more appropriate for reversal learning tasks. Second, the contrast between the response to the positive and negative stimuli was narrower in old dogs, compared to young dogs, during the reversal learning task, as well as the cognitive bias test. This measure favors comparability between tasks and between studies. Following the cognitive bias test, we could not find any indication of differences in the positive and negative expectations between young and old dogs. Taken together, these findings do not support the hypothesis that old dogs have more negative expectations than young dogs and the use of the cognitive bias test in older dogs requires further investigation.     

Discrimination reversal learning in newts

The results of field research suggest that, contrary to being behaviorally inflexible, some amphibians may have the ability to respond effectively to changing environments. The performance of seven newts (Triturus viridescens) was studied across 20 successive reversals of a spatial discrimination problem in a dry T-maze. Submersion in shaded water served as reinforcement for correct responses. The subjects showed a decrease in mean errors across reversals and across ordinal trials within sessions. These results are discussed in terms of the importance of using biologically relevant methodologies in the study of comparative animal learning.     

Sensory-specific associations in flavor-preference reversal learning

In two experiments, we examined the effect of reversal learning on the status of initially learned associations. In Experiment 1, thirsty rats were first taught to associate one flavor with sucrose and another flavor with Polycose. These relations were then reversed in a subsequent phase. One of the nutrients was then devalued by being paired with lithium chloride. The results of a two-bottle flavor-choice test revealed that the most recently learned associations governed performance. In Experiment 2, we aimed to discern whether the initially learned associations in Experiment 1 were weakened or masked by reversal learning. In order to address this question, either a 1-day (Group Immediate) or a 21-day (Group Delayed) retention interval was interpolated between the reversal and devaluation phases. Subsequent flavor-choice tests revealed that Group Immediate avoided the flavor most recently associated with the devalued nutrient but that Group Delayed avoided the flavor that was initially associated with the devalued nutrient. These findings suggest that the second-learned associations do not erase, but transiently mask, the first-learned associations, which subsequently recover over a retention interval. These results suggest a parallel in the mechanisms of extinction and reversal learning.     

Serial learning,interitem associations,phrasing cues,interference, overshadowing,chunking, memory,and extinction

Two experiments indicated that two approaches to serial learning are too extreme—the classical view that it consists only of interitem associations and various recent views that it involves no interitem associations. The novel assumption introduced here was that phrasing cues, normally conceptualized as merely segregating long series into smaller units or chunks, may also enter into associations with items, thereby reducing interitem interference and facilitating serial learning. It was found that one item could become a signal for another item, an interitem association, or be overshadowed by a phrasing cue, such as a brightness and temporal cue, also signaling that item. The items were .045-g pellets. Rats traversed a runway for items arranged in ordered series, 14-7-3-1-0 pellets (Experiment 1) or 10-2-0-10 (Experiment 2). Complete tracking of, for example, the 10-2-0-10 series would consist of fastest running to 10 pellets and slowest running to 0 pellets. In both investigations, the interitem association overshadowed was that between 0 pellets and the subsequent rewarded item, 0 → 14 (Experiment 1) or 0 → 10 (Experiment 2). Either repetitions of the 14-7-3-1-0 subpattern (Experiment 1) or merely the terminal 10-pellet item (Experiment 2) were phrased, both methods producing identical results. Overshadowing the 0-pellet item produced superior serial learning, more rapid extinction, and, in Experiment 1, considerable elevation of responding when the brightness phrasing cue was introduced in extinction, an effect said to be conceptually identical to spontaneous recovery and one demonstrating directly that phrasing cues are in reality overshadowing cues. It was suggested that many effects attributed to forgetting may be due to unrecognized overshadowing of memory cues by phrasing cues, giving rise to exaggerated estimates of forgetting.     

The impact of context relevance during extinction learning

In two predictive-learning experiments, we investigated the role of the informational value of contexts for the formation of context-specific extinction learning. The contexts were each composed of two elements from two dimensions, A and B. In Phase 1 of each experiment, participants received acquisition training with a target cue Z in context A1B1 (the numbers assign particular values on the context dimensions). In Phase 2, participants were trained with conditional discriminations between two other cues, X and Y, for which only one of the two context dimensions was relevant. In a third phase, participants received extinction trials with cue Z in context A2B2. During a final test phase, we observed that a partial change of the extinction context disrupted extinction performance when the extinction context was changed on the dimension that had been trained as being relevant for the conditional discrimination. However, when the extinction context was changed on the irrelevant context dimension, extinction performance was not affected. Our results are consistent with the idea that relevant contexts receive more attention than do irrelevant contexts, leading to stronger context-specific processing of information learned in the former than in the latter type of contexts.     

Two-choice,observational learning and reversal in the rat: S-S versus S-R effects

In Experiment 1, male rats were trained to press both bars in a two-choice apparatus and were then given observational training of a go/no-go discrimination in which the observed operation of two inaccessible, dissimilar bars by a hidden experimenter constituted S+ and S?. After discrimination was established, individual rats were permitted access to the two bars. Six of the seven rats consistently pressed the S+ bar on 10 test trials, but failed to reverse bar preference after observational training was reversed. In Experiment 2, nine naive males received the same observational training as in Experiment 1, but without any pretraining to press either bar. All rats pressed the S+ bar on initial test and did so consistently throughout the 10 trials. Six of these rats received reversal training of the go/no-go discrimination after the 10 test trials. As in Experiment 1, all rats failed to press the new S+ bar. However, five of six rats in another group, which received reversal trainingprior to any test trials, did reverse and press the new S+ bar. In Experiment 3, controls for possible confounding effects of overtraining trials were conducted. These manipulations had no effect; the rats tested before reversal still failed to press the S+ bar, and the rats reversed before testing all reversed or pressed the most recent S+ bar. That is, S-R learning predominated over S-S learning if active, though unreinforced, responding to a particular bar intervened. In contrast, however, a cognitive (S-S) interpretation of directed response learning was supported by the results of Experiment 4, in which the rats that learned the go/no-go discrimination without responding (only by auditory and light cues) failed to press the S+ bar consistently.     

Discriminated avoidance learning and reversal by goldfish in a shuttlebox using a linear presentation procedure

Goldfish, trained in a shuttlebox with cues and shock controlled by a linear presentation procedure, learned to control prevailing cue states and shock, and thus to discriminatively avoid shock presentation. The linear presentation procedure, adapted for the shuttlebox from the sequence of cue presentation occurring in the Y-maze, utilized three cues on each trial, a trial-start (TS) cue, a shock-paired (S?) cue, and an unpaired (S+) cue. At trial onset (TS cue), the goldfish had 10 sec to respond. The first response produced, via response-contingent programming, either the shock-paired (S?) or unpaired (S+) cue, and subsequent responses produced alternation of S+ and S?. The shock was omitted only if the S+ cue state prevailed 10 sec after trial onset. AU other cue states (TS and S?) were paired with shock. Goldfish learned to respond and control the prevailing cue state so that the S+ cue prevailed at 10 sec posttrial onset for a variety of different color-cue combinations and also learned to reverse their originally learned cue preference when the color cues were reversed. The linear presentation procedure represents an alternative discrimination learning procedure that appears to be free of the interpretational problems encountered in training goldfish in the shuttlebox apparatus with other one- and two-stimulus procedures.     

Omission training compared with yoked controls and extinction in multiple-schedule discrimination learning

After rats were trained on a multiple schedule with variable interval 30-sec reinforcement in both stimulus components, omission, yoked, and extinction procedures were applied in S? while the variable interval continued in S+. In S?, omission training reduced response rate faster and to a lower terminal level than either response-independent yoked reinforcement or extinction, which were approximately equivalent. In S+, the extinction group exhibited elevated response rates representing behavioral contrast, while the omission and yoked groups showed reduced response rates. These results attest to the effectiveness of omission training as a response elimination method. They also contradict theories which posit reduction of response rate in S? to be necessary and sufficient for behavioral contrast.     

Expertise reversal effect and sequencing of learning tasks in online English as a second language learning environment

The aim of this paper is to examine the effects of sequencing instructional materials and learners' prior knowledge on learning ESL (English as a second language) through an online learning course. 121 fifth-grade students from an elementary school in Korea participated in the study. Each participant was allocated to one cell of a 2?×?2 between-subjects factorial design, with an instructional format (i.e. sequential or concurrent) as a first factor, and prior knowledge (i.e. high or low) as a second factor. Instructions of the words and grammar rules were allocated to each page for the sequential group, whereas integrated on a single page for the concurrent group. The result indicates that the sequential instruction of words followed by grammar explanations was more effective for the students with higher levels of prior knowledge than the concurrent presentation. The reverse was also found for the students with lower levels of prior knowledge in English. There are four possible explanations for the results. First, split-attention effect, temporal-contiguity effect, or transient information effect might occur. Second, worked-example effect might occur and over-ride the effect of sequencing. Third, intrinsic and extraneous cognitive load might intertwine each other. Last, the levels of element interactivity in two instructional formats might be different from each other. The implications for instructional designers and future research are discussed.     

Effects of cross-modal transfer on direct and reversal learning in the rat

In the first experiment, using within- and between-sensory modality CSs, direct and reversal transfer of active avoidance learning was studied in 48 male and 48 female albino rats. Training in each of two sessions employed either a high- or low-intensity light or noise CS. The analyses of both raw score data and proportional or savings score data indicated significant cross-modal transfer in direct as well as reversal learning conditions. Although females learned faster than males, there were no sex differences in amount of transfer. A second experiment, which examined the potential of compound conditioning within the cross-modal learning procedures, replicated the cross-modal results of the first experiment without finding evidence for compound conditioning. These results are interpreted in terms of specific and nonspecific transfer effects during avoidance learning.     

Simultaneous discrimination reversal learning in pigeons and humans: anticipatory and perseverative errors

Pigeons were trained on a two-choice simultaneous discrimination (red vs. green) that reversed midway through each session. After considerable training, they consistently made both anticipatory errors prior to the reversal and perseverative errors after the reversal, suggesting that time (or number of trials) into the session served as a cue for reversal. In Experiment 2, to discourage the use of time as a cue, we varied the location of the reversal point within the session such that it occurred semirandomly after Trial 10, 25, 40, 55, or 70. Pigeons still tended both to anticipate and to perseverate. In Experiment 3, we required 20 pecks to a stimulus on each trial to facilitate memory for the preceding response and sensitivity to local reinforcement contingencies, but the results were similar to those of Experiment 2. We then tested humans on a similar task with a constant (Experiment 4) or variable (Experiment 5) reversal location. When the reversal occurred consistently at the midpoint of the session, humans, like pigeons, showed a tendency to anticipate the reversal; however, they did not show perseverative errors. When the reversal location varied between sessions, unlike pigeons, humans adopted a win–stay/lose–shift strategy, making only a single error on the first trial of the reversal.     

Amount of training and reversal learning with singly presented stimuli in the rat

In a discrete trials multiple reversal experiment with singly presented stimuli, rats were given either 10 or 20 training trials per day for 2 days on each problem. All subjects improved progressively over reversals, but subjects with more training on each problem showed greater inhibition of responding to S? during reversal than those having less training. For both groups, the S? within sessions curve became steeper over reversals. Inhibition of responding to S? was greater on Day 2 of a reversal than on Day 1. The rat data are discussed in relation to those obtained from pigeons and goldfish.     

Dissociation of patterned alternation learning and the partial reinforcement extinction effect in preweanling rats

Sprague-Dawley rat pups aged 14 or 18 days were trained on a patterned (single) alternation schedule with either an 8- or a 105-sec intertriai interval (ITI). At the 8-sec ITI, alternation learning was obtained at both ages, but the older age group learned more rapidly. There was no evidence of response alternation at the 105-sec ITI at either age. Continuously reinforced (CRF) and partially reinforced (PRF) groups trained and extinguished along with the patterned alternation (PA) group at the 105-sec ITI showed a robust partial reinforcement extinction effect (PREE) at both ages. Moreover, there was no difference in the rate of extinction of the PRF and PA groups at either age (i.e., no effect of N-length). A PREE can therefore be obtained in infant rats under conditions that apparently preclude the formation of sequential associations. The implications of this finding for the ontogeny of instrumental learning and extinction are discussed.     

Partial reinforcement effects on learning and extinction of place preferences in the water maze

In two experiments, two groups of rats were trained in a navigation task according to either a continuous or a partial schedule of reinforcement. In Experiment 1, animals that were given continuous reinforcement extinguished the spatial response of approaching the goal location more readily than animals given partial reinforcement—a partial reinforcement extinction effect. In Experiment 2, after partially or continuously reinforced training, animals were trained in a new task that made use of the same reinforcer according to a continuous reinforcement schedule. Animals initially given partial reinforcement performed better in the novel task than did rats initially given continuous reinforcement. These results replicate, in the spatial domain, well-known partial reinforcement phenomena typically observed in the context of Pavlovian and instrumental conditioning, suggesting that similar principles govern spatial and associative learning. The results reported support the notion that salience modulation processes play a key role in determining partial reinforcement effects.     

Extinction produces context inhibition and multiple-context extinction reduces response recovery in human predictive learning

Two experiments with human participants were used to investigate recovery of an extinguished learned response after a context change using ABC designs. In an ABC design, the context changes over the three successive stages of acquisition (context A), extinction (context B), and test (context C). In both experiments, we found reduced recovery in groups that had extinction in multiple contexts, and that the extinction contexts acquired inhibitory strength. These results confirm those of previous investigations, that multiple-context extinction can produce less response recovery than single-context extinction, and they also provide new evidence for the involvement of contextual inhibitory processes in extinction in humans. The foregoing results are broadly in line with a protection-from-extinction account of response recovery. Yet, despite the fact that we detected contextual inhibition, predictions based on protection-from-extinction were not fully reliable for the single- and multiple-context group differences that we observed in (1) rates of extinction and (2) the strength of context inhibition. Thus, although evidence was obtained for a protection-from-extinction account of response recovery, this account can not explain all of the data.     

Acquisition,extinction, and reacquisition of a conditional discrimination to avoid shock by goldfish

Goldfish, trained in the shuttlebox to avoid shock, were tested for the acquisition and extinction of a color-matching or a color-oddity conditional discrimination choice response, and then tested for reacquisition. Extinction affected the accuracy of the choice response but not the number of trials with response (response strength). Half of all groups were extinguished with changed signal colors, and half had the same signal colors experienced in acquisition. All groups had the same signal colors in reacquisition that they had experienced in acquisition. Changed-signal oddity groups decremented slightly faster than same-signal oddity groups, providing some support for a generalization decrement interpretation, but same- and changed-signal matching groups did not differ. All groups extinguished on the choice response by the end of extinction. All matching groups, and all oddity groups, regardless of their respective signal colors in extinction, reacquired at the same rate, and faster than in acquisition. These results imply conceptual generalization of extinction effects. Matching-trained groups were found to be slightly superior to oddity-trained groups in both acquisition and reacquisition. Comparisons of these results to positive reinforcement conditional discrimination extinction work, including some procedural suggestions, are made.     

Living by learning, learning by living: The quest for meaning

In our current age of rapid social, economic and technological change, including urbanisation, globalisation and information overload, human beings are more than ever seeking orientation and meaning. In this situation, education is the potential key to individual empowerment, cultural prosperity, social cohesion and economic development. Arguing for the learning city as the location where a real learning culture is being developed, the author of this article discusses the need to build a new citizenship involving democratic, social, egalitarian (gender-balanced), intercultural and environmental dimensions. Based on a new humanism, this new citizenship should be designed to overcome the exclusion of many in the interests of a few and enable a meaning-friendly evolution in our social institutions. Thus the means of knowing, understanding and being in the world of knowledge, which are essential for liberating the human mind, can be provided to everyone.