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PubMed1963

All-or-none learning and the role of repetition in paired-associate learning.

The learning of a list of stimulus-response items is a two-stage process involving response learning and association. It is assumed that both stages are learned in an all-or-none fashion. Subjects were trained to learn a list of paired-associate items with Rock's substitution procedure. Their performance could be predicted from the all-or-none theory with parameter estimates based upon the performance of a different group of subjects who learned the same items under normal conditions.

Humans↗
PubMed2005

Processing abstract sequence structure: learning without knowing, or knowing without learning?

Constant interaction with a dynamic environment-from riding a bicycle to segmenting speech-makes sensitivity to the sequential structure of the world a fundamental dimension of information processing. Accounts of sequence learning vary widely, with some authors arguing that parsing and segmentation processes are central, and others proposing that sequence learning involves mere memorization. In this paper, we argue that sequence knowledge is essentially statistical in nature, and that sequence learning involves simple associative prediction mechanisms. We focus on a choice reaction situation introduced by Lee (1997), in which participants were exposed to material that follows a single abstract rule, namely that stimuli are selected randomly, but never appear more than once in a legal sequence. Perhaps surprisingly, people can learn this rule very well. Or can they? We offer a conceptual replication of the original finding, but a very different interpretation of the results, as well as simulation work that makes it clear how highly abstract dimensions of the stimulus material can in fact be learned based on elementary associative mechanisms. We conclude that, when relevant, memory is optimized to facilitate responding to events that have not occurred recently, and that sequence learning in general always involves sensitivity to repetition distance.

Adolescent↗
PubMed2006

Students' conceptions of constructivist learning: a comparison between a traditional and a problem-based learning curriculum.

This study investigated students' conceptions of constructivist learning activities in a problem-based learning (PBL) and a traditional curriculum. We examined whether students who have chosen for a problem-based curriculum have different conceptions of constructivist assumptions compared to students who have chosen to be enrolled in a traditional, lecture-based curriculum when they enter university. Although constructivism represents an influential view of learning, studies investigating how students conceptualize this perspective have not been conducted before. A structural equation modelling approach was adopted to test the hypothesized model in both student populations and to calculate latent means. Results suggested that students in the PBL environment agree more on constructivist assumptions of cooperative learning and the use of authentic problems, while students in the traditional curriculum acknowledge the importance of motivation to learn more. It is discussed that conceptions of constructivist learning activities can act as an important moderator of PBL effects and should be considered in examining the effects of PBL and probably in all comparative education research.

Adult↗
PubMed1994

Perceptual learning: learning to see.

Perceptual learning in vision has been found to be highly specific for simple stimulus attributes, implying highly specific modifications in the nervous system. The type of specificity found (location, orientation, eye) implied plasticity at very early stages of visual processing, where processing modules were believed to be hard-wired and task independent. Recent studies show, however, that learning is task dependent. Studies examining the time course of learning indicate that at least two different learning processes are involved in perceptual learning, reflecting different levels of processing. Perceptual learning appears to be governed by associative rules and to be constrained by system architecture.

Electrophysiology↗
PubMed2004

Learning at a distance II. Statistical learning of non-adjacent dependencies in a non-human primate.

In earlier work we have shown that adults, infants, and cotton-top tamarin monkeys are capable of computing the probability with which syllables occur in particular orders in rapidly presented streams of human speech, and of using these probabilities to group adjacent syllables into word-like units. We have also investigated adults' learning of regularities among elements that are not adjacent, and have found strong selectivities in their ability to learn various kinds of non-adjacent regularities. In the present paper we investigate the learning of these same non-adjacent regularities in tamarin monkeys, using the same materials and familiarization methods. Three types of languages were constructed. In one, words were formed by statistical regularities between non-adjacent syllables. Words contained predictable relations between syllables 1 and 3; syllable 2 varied. In a second type of language, words were formed by statistical regularities between non-adjacent segments. Words contained predictable relations between consonants; the vowels varied. In a third type of language, also formed by regularities between non-adjacent segments, words contained predictable relations between vowels; the consonants varied. Tamarin monkeys were exposed to these languages in the same fashion as adults (21 min of exposure to a continuous speech stream) and were then tested in a playback paradigm measuring spontaneous looking (no reinforcement). Adult subjects learned the second and third types of language easily, but failed to learn the first. However, tamarin monkeys showed a different pattern, learning the first and third type of languages but not the second. These differences held up over multiple replications, using different sounds instantiating each of the patterns. These results suggest differences among learners in the elementary units perceived in speech (syllables, consonants, and vowels) and/or the distance over which such units can be related, and therefore differences among learners in the types of patterned regularities they can acquire. Such studies with tamarins open interesting questions about the perceptual and computational capacities of human learners that may be essential for language acquisition, and how they may differ from those of non-human primates.

Animals↗
PubMed2006

Learning in context: linguistic and attentional constraints on children's color term learning.

Three experiments investigated whether linguistic and/or attentional constraints might account for preschoolers' difficulties when learning color terms. Task structure and demands were equated across experiments, and both speed and degree of learning were compared. In Experiment 1, 3-year-olds who were matched on vocabulary score were taught new secondary color terms by corrective, semantic, or referential linguistic contrast. Corrective contrast produced more rapid and more extensive learning than did either semantic or referential contrast, supporting the hypothesis that targeted linguistic feedback facilitates learning. Experiment 2 replicated and extended the first experiment with Italian children and found cross-cultural differences in the amount learned about colors named differently in the two languages. In Experiment 3, some of the children were introduced to the new terms within a context of enhanced perceptual salience. These children learned as fast and performed as accurately as those given corrective linguistic feedback in Experiment 1.

Attention↗
PubMed2005

A comparison of problem-based learning and lecture-based learning in an adult health nursing course.

PURPOSE: This study aimed to compare the effects of the problem-based learning (PBL) method with the traditional lecture method on learning in the cardiorespiratory nursing section of the Adult Health Nursing course. METHOD: A pretest-posttest experimental design was used. A total of 71 second-year nursing students in a three-year nursing program in Korea participated: 35 students in the PBL group in the fall semester of 2002, and 36 students in the traditional lecture group in 2003. The seven PBL packages were developed by the authors, based on an analysis of relevant learning content and clinical scenarios. RESULTS: The level of knowledge in the PBL group was significantly higher than that of students in the lecture group (t=2.007, p=.045). All PBL students with higher and lower grades showed a significant increase in the posttest score. But in the lecture group, only students with higher grades showed a notable increase. No statistically significant difference was found between the PBL and lecture groups in the level of attitude toward learning (t=1.669, p=.100). Learning motivation was significantly higher in the PBL group (t=2.608, p=.012). CONCLUSION: Students in the PBL group gained more knowledge and had higher motivation toward learning compared to students in the lecture group.

Adult↗
PubMed2005

Hippocampal replay contributes to within session learning in a temporal difference reinforcement learning model.

Temporal difference reinforcement learning (TDRL) algorithms, hypothesized to partially explain basal ganglia functionality, learn more slowly than real animals. Modified TDRL algorithms (e.g. the Dyna-Q family) learn faster than standard TDRL by practicing experienced sequences offline. We suggest that the replay phenomenon, in which ensembles of hippocampal neurons replay previously experienced firing sequences during subsequent rest and sleep, may provide practice sequences to improve the speed of TDRL learning, even within a single session. We test the plausibility of this hypothesis in a computational model of a multiple-T choice-task. Rats show two learning rates on this task: a fast decrease in errors and a slow development of a stereotyped path. Adding developing replay to the model accelerates learning the correct path, but slows down the stereotyping of that path. These models provide testable predictions relating the effects of hippocampal inactivation as well as hippocampal replay on this task.

Algorithms↗
PubMed2006

Heterarchical reinforcement-learning model for integration of multiple cortico-striatal loops: fMRI examination in stimulus-action-reward association learning.

The brain's most difficult computation in decision-making learning is searching for essential information related to rewards among vast multimodal inputs and then integrating it into beneficial behaviors. Contextual cues consisting of limbic, cognitive, visual, auditory, somatosensory, and motor signals need to be associated with both rewards and actions by utilizing an internal representation such as reward prediction and reward prediction error. Previous studies have suggested that a suitable brain structure for such integration is the neural circuitry associated with multiple cortico-striatal loops. However, computational exploration still remains into how the information in and around these multiple closed loops can be shared and transferred. Here, we propose a "heterarchical reinforcement learning" model, where reward prediction made by more limbic and cognitive loops is propagated to motor loops by spiral projections between the striatum and substantia nigra, assisted by cortical projections to the pedunculopontine tegmental nucleus, which sends excitatory input to the substantia nigra. The model makes several fMRI-testable predictions of brain activity during stimulus-action-reward association learning. The caudate nucleus and the cognitive cortical areas are correlated with reward prediction error, while the putamen and motor-related areas are correlated with stimulus-action-dependent reward prediction. Furthermore, a heterogeneous activity pattern within the striatum is predicted depending on learning difficulty, i.e., the anterior medial caudate nucleus will be correlated more with reward prediction error when learning becomes difficult, while the posterior putamen will be correlated more with stimulus-action-dependent reward prediction in easy learning. Our fMRI results revealed that different cortico-striatal loops are operating, as suggested by the proposed model.

Association Learning↗
PubMed2005

Perceptual learning of Gabor orientation identification in visual periphery: complete inter-ocular transfer of learning mechanisms.

We combined the external noise paradigm, the Perceptual Template Model approach, and transfer tests to investigate the mechanisms and eye-specificity of perceptual learning of Gabor orientation in visual periphery. Coupled with a fixation task, discriminating a 5 from an S in a rapid small character string at fixation, contrast thresholds were estimated for each of eight external noise levels at two performance criteria using 3/1 and 2/1 staircases. Perceptual learning in one eye was measured over 10 practice sessions, followed by five sessions of practice in the new eye to assess transfer. We found that monocular learning improved performance (reduced contrast thresholds) with virtually equal magnitude across a wide range of external noise levels with no significant change in central task performance. Based on measurements of learning effects at two performance criterion levels, we identified a mixture of stimulus enhancement and external noise exclusion as the mechanism of perceptual learning underlying the observed improvements. Perceptual learning in the trained eye generalized completely to the untrained eye. We related the transfer patterns to known physiology and psychophysics on orientation direction coding.

Contrast Sensitivity↗
PubMed1996

Dissociable effects of anterior and posterior cingulate cortex lesions on the acquisition of a conditional visual discrimination: facilitation of early learning vs. impairment of late learning.

Two experiments investigated the effects of quinolinic acid induced lesions of the anterior and posterior cingulate cortices on the acquisition and performance of a conditional visual discrimination (CVD) task, in which rats were required to learn a rule of the type: "If lights are flashing FAST, press the right lever; if SLOW press left". In Experiment 1, animals with lesions of the anterior cingulate cortex (ANT group) demonstrated a significant enhancement in learning during the early stages of task acquisition. Conversely, animals with lesions of the posterior cingulate cortex (POS group) were impaired in learning during the later stages of acquisition. There were no significant differences between the ANT and POS groups on the performance of the task when either variable inter-trial intervals or reduced stimulus durations were imposed. In Experiment 2, the specificity of the lesion effects for processes operative during the early and late stages of learning was tested. Animals were trained to a criterion of 70% correct choices on two consecutive sessions prior to lesioning, and subsequently allowed to continue to acquire the task to the mean asymptotic performance level of 85% correct choices on two consecutive sessions. Animals of the POS group were impaired in learning during this later stage of task acquisition, thus replicating the pattern of results obtained in Experiment 1. The animals in Experiment 2 were then tested following a 30-day retention interval and during extinction (removal of sucrose from the magazine). The extinction test revealed an impairment in the ability of animals in the ANT group to omit lever responses in the absence of reinforcement. These results indicate that the anterior and posterior cingulate cortices are functionally dissociable, and suggest that they may form part of complementary, but competing, learning and memory systems.

Animals↗
PubMed2002

Place-learning, but not cue-learning training, modifies the hippocampal theta rhythm in rats.

Hippocampal theta activity accompanies behaviours such as running, swimming, head movements and spatially orientated responses in the rat. However, whether a relationship between this activity and information processing exists remains unclear. As place-learning depends on hippocampal integrity, whereas cue-learning does not, the hippocampal theta activity underlying each test was evaluated. Local CA1 hippocampal electroencephalograms (EEGs) were recorded over 6 days in a Morris maze for one place-learning test group of rats (n=10) and one cue-learning test group (n=8). The EEG of the corresponding test was taken during waking immobile, searching, and on-platform stages. The relative power (RP) values of EEGs were divided into 4-6.5Hz, 6.5-9.5Hz, and 9.5-12Hz frequency sub-bands. The place-learning training produced a separation of 4-6.5Hz and 6.5-9.5Hz sub-bands in searching and platform stages and a higher activity on the 6.5-9.5Hz sub-band during searching, compared with the basal record, while the cue-learning group did not show differences related either to the training or behavioural stage. As the motor activity and swimming velocity was similar in both groups, the results strongly suggest that the changes observed in theta activity reflect information processing by the hippocampus.

Action Potentials↗
PubMed2000

Use of key words as an adjunctive learning tool improves learning during a perioperative medicine rotation for anesthesiology residents.

Designing a successful block rotation for anesthesiology residents requires not only an appropriate curriculum but also a set of teaching tools, which promote learning. Traditional clinical rotations in Anesthesiology residencies emphasize clinical teaching, supported by interaction with staff. Since Perioperative Medicine is a nontraditional subject for anesthesia residents, we introduced a syllabus and didactic curriculum to support clinical teaching. We hypothesized that the use of key words would enhance learning. Alternating groups of residents were assigned to receive key words, while control residents were expected to learn without key words. The key words were delivered in writing on the first day of the rotation and the syllabus was highlighted to identify the key words in the text. Pretests and posttests were administered to residents participating in the perioperative rotation. Learning was assessed by calculating the change in test scores. There was significantly more learning in the group given the key words. We conclude that key word designation improved learning in a rotation designed to teach perioperative medicine.

Anesthesiology↗
PubMed1985

Cortical substrates of taste aversion learning: involvement of dorsolateral amygdaloid nuclei and temporal neocortex in taste aversion learning.

The amygdaloid complex is functionally implicated in conditioned taste aversion (CTA) learning. Results of previous neurobehavioral studies have provided equivocal evidence concerning the involvement of specific amygdaloid nuclei in CTA learning. The present study was conducted to examine the involvement of the central (CE), lateral (LA), and basolateral (BL) amygdaloid nuclei and the temporal neocortices (area 20) in CTA learning. To that end, distinct groups of rats received bilateral electrolytic lesion placements in the CE, LA, BL, or the temporal neocortices. Control animals received scalp and meningeal incisions only. Following recovery, animals were habituated to a restricted drinking schedule with distilled water. Animals then received CTA conditioning, with LiCl used both as the conditioned stimulus and as the unconditioned stimulus. Anterograde degeneration histologies were performed on all brain tissue to evaluate relations between CTA learning deficits and axonal pathology induced by lesion placements. Results of behavioral manipulations indicated that destruction of the CE, LA, or temporal neocortex impaired CTA acquisition, but damage induced to the basolateral amygdaloid nucleus did not. Anatomical observations indicated that degeneration of amygdalofugal and/or corticofugal projections to the convolutions of the olfactory tubercle (medial), subthalamic nucleus, and the parabrachial complex is correlated with CTA learning deficits. These results indicate that destruction of the dorsolateral amygdaloid nuclei and/or the temporal neocortices may produce CTA learning deficits by affecting olfactory, gustatory, and/or gastrointestinal processing in various portions of the forebrain.

Amygdala↗
PubMed1985

Thalamocortical relations in taste aversion learning: I. Involvement of gustatory thalamocortical projections in taste aversion learning.

The anterior insular gustatory neocortex (AIGN) has been implicated as a functional substrate of conditioned taste aversion (CTA) learning. Results of previous neuroanatomical and neurobehavioral experiments indicate that projections from gustatory-responsive neurons in the posterior ventromedial thalamic nuclei (parvicellular division; VPMpc) may provide relevant input to the AIGN during CTA learning. In rat, gustatory thalamocortical projections from VPMpc thalamus traverse the ventrolateral neostriatum (VLS) enroute to the AIGN. In these experiments, various neuroanatomical and neurobehavioral manipulations in the VLS were used to examine the contribution of presumed gustatory thalamocortical projections to CTA learning. These experiments demonstrate that projections from VPMpc thalamus to the AIGN are essential for normal CTA learning. Because both VPMpc thalamus and the AIGN each have been implicated as functional substrates of CTA learning, the present results suggest that the gustatory thalamocortical relay per se is necessary for normal taste-illness learning.

Afferent Pathways↗
PubMed1997

Intact mirror-tracing and impaired rotary-pursuit skill learning in patients with Huntington's disease: evidence for dissociable memory systems in skill learning.

Skill learning in early-stage Huntington's disease (HD) patients was compared with that of normal controls on 2 perceptual-motor tasks, rotary pursuit and mirror tracing. HD patients demonstrated a dissociation between impaired rotary-pursuit and intact mirror-tracing skill learning. These results suggest that different forms of perceptual-motor skill learning are mediated by separable neural circuits. A striatal memory system may be essential for sequence or open-loop skill learning but not for skills that involve the closed-loop learning of novel visual-response mappings. It is hypothesized that working memory deficits in HD resulting from frontostriatal damage may account broadly for intact and impaired long-term learning and memory in HD patients.

Adult↗
PubMed2004

Learning as a task or a virtue: U.S. And Chinese preschoolers explain learning.

The purpose of this study was to examine cultural influences on conceptual orientations of learning in U.S. and Chinese preschoolers. A sample of 188 preschoolers 4-6 years of age provided free-narrative responses to 2 story beginnings about the learning behavior of 2 protagonists, 1 who worked hard and 1 who gave up. Results showed that despite some differences in the younger age groups, children from both cultures valued learning similarly at age 6. However, important cultural differences emerged in children's construals of the learning process. U.S. children showed a heightened awareness of the mind/task attributes of the learner, that is, ability, task attempting, and strategy use. By contrast, Chinese children perceived more the learner's dispositional qualities of diligence, persistence, and concentration. These trends increased as children's age increased. The U.S. findings are interpreted as reflecting the U.S. cultural emphasis on learning as a task, and the Chinese results, as reflecting the Chinese cultural focus on learning as a process of cultivating personal virtue.

Attitude↗
PubMed2005

The outcome specificity of learned predictiveness effects: parallels between human causal learning and animal conditioning.

Two experiments examined the outcome specificity of a learned predictiveness effect in human causal learning. Experiment 1 indicated that prior experience of a cue-outcome relation modulates learning about that cue with respect to a different outcome from the same affective class but not with respect to an outcome from a different affective class. Experiment 2 ruled out an interpretation of this effect in terms of context specificity. These results indicate that learned predictiveness effects in human causal learning index an associability that is specific to a particular class of outcomes. Moreover, they mirror demonstrations of the reinforcer specificity of analogous effects in animal conditioning, supporting the suggestion that, under some circumstances, human causal learning and animal conditioning reflect the operation of common associative mechanisms.

Adolescent↗