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PubMed2006

Prenatal alcohol exposure alters GABA(A)alpha5 expression: a mechanism of alcohol-induced learning dysfunction.

OBJECTIVE: In a model for fetal alcohol syndrome (FAS), we have previously found an alteration in NMDA receptors suggesting mediation, at least in part, of alcohol-related learning deficit. NMDA and GABA receptors interact in a multisynaptic circuit for the regulation of the inhibitory tone through the CNS. The GABA receptor subunit GABA(A)alpha5 is involved in learning and is developmentally regulated, as it is excitatory in the perinatal brain and inhibitory in the adult. We were interested to evaluate alcohol's effect on GABA(A)alpha5 expression to further understand alcohol-induced learning dysfunction. STUDY DESIGN: Timed, pregnant C57B16/J mice were treated on gestational day 8 with alcohol (25% alcohol, 0.03 mL/kg i.p.) or control (saline). Embryos and brains were harvested 10 days after treatment, and brains from adult offspring were collected after evaluation in the Morris Water Maze, a well-established test for spatial learning. Gene expression included samples from at least 3 litters per timepoint, and calibrator-normalized relative real-time polymerase chain reaction (PCR) was performed to quantify GABA(A)alpha5 with GAPDH standardization. Statistical analysis included analysis of variance (ANOVA). RESULTS: Prenatal alcohol exposure significantly decreased GABA(A)alpha5 expression in the embryo (P < .02) and fetal brains (P < .01) 10 days after therapy. However, in adult brains GABA(A)alpha5 expression was increased versus controls (P < .01). As previously demonstrated, prenatal alcohol exposure resulted in deficits in adults learning the Morris Water Maze with controls learning faster (P < .05). CONCLUSION: Prenatal alcohol exposure alters developmental GABA(A)alpha5 expression. This may further explain the long-lasting damage of alcohol on learning skills. Both the alcohol-induced reduction in the GABA(A)alpha5 subunit during development and up-regulation in adult brain may be related to learning deficits resulting in decreased learning potential caused by the developmental defect and an increased inhibition of learning resulting from increased expression as an adult. In combination with our previous findings, these suggest that alcohol-induced learning impairment is likely the result of alterations of both NMDA and GABA expression and function.

Animals↗
PubMed2004

Learning-related fMRI activation associated with a rotational visuo-motor transformation.

The unique ability to learn transformed or altered visuo-motor relationships during motor learning (visuo-motor transformation learning) has engaged researchers for over a century. Compared to other forms of motor learning (e.g., sequence learning), little is known about plasticity in the cortical and/or subcortical systems involved. We used fMRI to isolate region-specific activation changes during the learning of a visuo-motor (joystick) task under a simple transformation (90 degree rotation of visual feedback). Distributed brain systems were engaged in the learning process. In particular, we found evidence of a learning-dependent transition from early activation of the posterior parietal cortex to later distributed cortico-subcortical-cerebellar responses (in the temporal and occipital cortices, basal ganglia, cerebellum and thalamus). The role of the posterior parietal cortex may relate specifically to the acquisition of the transformation, while that of the fusiform and superior temporal gyri may reflect higher level visual and visuo-spatial processing underlying consolidation. Learning-related increases in cerebellar responses are consistent with its proposed role in the acquisition of internal models of the motor apparatus. These learning-related changes suggest a role for interacting neural systems involving the co-operation of cortico-cortico, cortico-cerebellar and cortico-basal ganglia loops during visuo-motor transformation learning.

Adult↗
PubMed2004

Awareness modifies the skill-learning benefits of sleep.

Behind every skilled movement lies months of practice. However, practice alone is not responsible for the acquisition of all skill; performance can improve between, not just within, practice sessions. An important principle shaping these offline improvements may be an individual's awareness of learning a new skill. New skills, such as a sequence of finger movements, can be learned unintentionally (with little awareness for the sequence, implicit learning) or intentionally (explicit learning). We measured skill in an implicit and explicit sequence-learning task before and after a 12 hr interval. This interval either did (8 p.m. to 8 a.m.) or did not (8 a.m. to 8 p.m.) include a period of sleep. Following explicit sequence learning, offline skill improvements were only observed when the 12 hr interval included sleep. This overnight improvement was correlated with the amount of NREM sleep. The same improvement could also be observed in the evening (with an interval from 8 p.m. to 8 p.m.), so it was not coupled to retesting at a particular time of day and cannot therefore be attributed to circadian factors. In contrast, in the implicit learning task, offline learning was observed regardless of whether the 12 hr interval did or did not contain a period of sleep. However, these improvements were not observed with only a 15 min interval between sessions. Therefore, the practice available within each session cannot account for these skill improvements. Instead, sufficient time is necessary for offline learning to occur. These results show a behavioral dissociation, based upon an individual's awareness for having learned a sequence of finger movements. Offline learning is sleep dependent for explicit skills but time dependent for implicit skills.

Awareness↗
PubMed2004

Consolidation of dynamic motor learning is not disrupted by rTMS of primary motor cortex.

Motor skills, once learned, are often retained over a long period of time. However, such learning first undergoes a period of consolidation after practice. During this time, the motor memory is susceptible to being disrupted by the performance of another motor-learning task. Recently, it was shown that repetitive transcranial magnetic stimulation (rTMS) over the primary motor cortex could disrupt the retention of a newly learned ballistic task in which subjects had to oppose their index finger and thumb as rapidly as possible. Here we investigate whether the motor cortex is similarly involved during the consolidation that follows learning novel dynamics. We applied rTMS to primary motor cortex shortly after subjects had either learned to compensate for a dynamic force field applied to their index finger or learned a ballistic finger abduction task. rTMS severely degraded the retention of the learning for the ballistic task but had no effect on retention of the dynamic force-field learning. This suggests that, unlike learning of simple ballistic skills, learning of dynamics may be stored in a more distributed manner, possibly outside the primary motor cortex.

Adult↗
PubMedDate not supplied

Surgery resident learning styles and academic achievement.

OBJECTIVE: To determine if surgical residents share a preferred learning style as measured by Kolb's Learning Style Inventory (LSI) and if a relationship exists between resident learning style and achievement as measured by a standardized examination (AME). Also, core faculty learning styles were assessed to determine if faculty and residents share a preferred learning style. DESIGN: Kolb's LSI, Version 3, was administered to 16 surgical residents and the residency program's core faculty of 6 attending physicians. To measure academic achievement, the American Medical Education (AME) examination was administered to residents. SETTING: The Hospital of Saint Raphael, General Surgery Residency Program, New Haven, Connecticut. Both instruments were administered to residents during protected core curriculum time. Core faculty were administered the LSI on an individual basis. PARTICIPANTS: Surgical residents of the Hospital of Saint Raphael's General Surgery Residency Program and 6 core faculty members RESULTS: Analysis of resident learning style preference revealed Converging as the most commonly occurring style for residents (7) followed by Accommodating (5), Assimilating (3), and Diverging (1). The predominant learning style for core faculty was also Converging (4) with 2 Divergers. The average score for the Convergers on the AME was 62.6 compared with 42 for the next most frequently occurring learning style, Accommodators. CONCLUSIONS: In this surgical residency program, a preferred learning style for residents seems to exist (Converging), which confirms what previous studies have found. Additionally, residents with this learning style attained a higher average achievement score as measured by the AME. Also, core faculty share the same preferential learning style as this subset of residents.

General Surgery↗
PubMed2005

Can patients with Alzheimer's disease learn a category implicitly?

Can a person with a damaged medial-temporal lobe learn a category implicitly? To address this question, we compared the performance of participants with mild Alzheimer's disease (AD) to that of age-matched controls in a standard implicit learning task. In this task, participants were first presented a series of objects, then told the objects formed a category, and then had to categorize a long sequence of test items [Knowlton B. J., Squire L. R. (1993). The learning of categories: parallel brain systems for item memory and category knowledge. Science, 262, 1747-1749]. We tested the hypotheses that: (1) both Control and AD participants would show evidence for implicit learning after the unwanted contribution of learning during test is removed; (2) the degree of implicit learning is the same for AD and Control participants; (3) training with exemplars that are highly similar to an unseen prototype will lead to better implicit category learning than training with exemplars that are less similar to a prototype. With respect to the first hypothesis, we found that both AD and Control participants performed better on tests of implicit learning than could be attributed to just learning on test trials. We found no clear means for evaluating our second hypothesis, and argue that comparisons of the degree of implicit learning between patient and control groups in this paradigm are confounded by the contribution of other memory systems. In line with the third hypothesis, only training with similar exemplars resulted in significant implicit category learning for AD participants.

Aged↗
PubMed2006

Changes in transcription within the CA1 field of the hippocampus are associated with age-related spatial learning impairments.

Aged rats display a broad range of behavioral performance in spatial learning. The aim of this study was to identify candidate genes that are associated with learning and memory impairments. We first categorized aged-superior learners and age learning-impaired rats based on their performance in the Morris water maze (MWM) and then isolated messenger RNA from the CA1 hippocampal region of each animal to interrogate Affymetrix microarrays. Microarray analysis identified a set of 50 genes that was transcribed differently in aged-superior learners that had successfully learned the spatial strategy in the MWM compared to aged learning-impaired animals that were unable to learn and a variety of groups designed to control for all non-learning aspects of exposure to the water maze paradigm. A detailed analysis of the navigation patterns of the different groups of animals during acquisition and probe trials of the MWM task was performed. Young animals used predominantly an allocentric (spatial) search strategy and aged-superior learners appeared to use a combination of allocentric and egocentric (response) strategies, whereas aged-learning impaired animals displayed thigmotactic behavior. The significant 50 genes that we identified were tentatively classified into four groups based on their putative role in learning: transcription, synaptic morphology, ion conductivity and protein modification. Thus, this study has potentially identified a set of genes that are responsible for the learning impairments in aged rats. The role of these genes in the learning impairments associated with aging will ultimately have to be validated by manipulating gene expression in aged rats. Finally, these 50 genes were functioning in the context of an aging CA1 region where over 200 genes was found to be differentially expressed compared to a young CA1.

Aging↗
PubMed2006

MAP2 and synaptophysin protein expression following motor learning suggests dynamic regulation and distinct alterations coinciding with synaptogenesis.

Learning a new motor skill can induce neuronal plasticity in rats. Within motor cortex, learning-induced plasticity includes dendritic reorganization, synaptogenesis, and changes in synapse morphology. Behavioral studies have demonstrated that learning requires protein synthesis. It is likely that some of the proteins synthesized during learning are involved in, or the result of, learning-induced structural plasticity. We predicted the expression of proteins involved in neural plasticity would be altered in a learning dependent fashion. Long-Evans rats were trained on a series of motor tasks that varied in complexity, so that the effects of activity could be teased apart from the effects of learning. The motor cortices were examined for MAP2 and synaptophysin protein using Western blotting and immunohistochemistry. Western blotting revealed that expression of MAP2 was not detectably influenced by learning, whereas synaptophysin expression increased on day 1, 3, and 5 of complex motor skill learning. Expression of MAP2 does not seem to indicate difficulty of task or duration of training time, whereas increases in synaptophysin expression, which appear diffusely across the cortex, seem to be correlated with the first 5 days of motor skill learning. Similar findings with GAP-43 suggest the change in synaptophysin may coincide with synapse formation. Immunohistochemistry did not reveal any localized changes in protein expression. These data indicate a difference in learning-induced expression in the mammalian brain compared to reports in the literature, which have often focused on stimulation to induce alterations in protein expression.

Adaptation, Physiological↗
PubMed2004

Visual discrimination learning in dwarf goats and associated changes in heart rate and heart rate variability.

We studied visual discrimination learning in a group of Nigerian dwarf goats using a computer-based learning device which was integrated in the animals' home pen. We conducted three consecutive learning tasks (T1, T2 and T3), each of which lasted for 13 days. In each task, a different set of four visual stimuli was presented on a computer screen in a four-choice design. Predefined sequences of stimulus combinations were presented in a pseudorandom order. Animals were rewarded with drinking water when they chose the positive stimulus by pressing a button next to it. Noninvasive measurements of goats' heartbeat intervals were carried out on the first and the last 2 days of each learning task. We analysed heart rate (HR) and heart rate variability (HRV) of resting animals to study sustained physiological effects related to general learning challenge rather than acute excitement during an actual learning session. The number of trials to reach the learning criterion was 1000 in T1, when visual stimuli were presented to the goats for the first time, but decreased to 210 in T2 and 240 in T3, respectively. A stable plateau of correct choices between 70% and 80% was reached on Day 10 in T1, on Day 8 in T2 and on Day 6 in T3. We found a significant influence of the task and of the interaction between task and day on learning success. Whereas HR increased throughout T1, this relationship was inverted in T2 and T3, indicating different effects on the HR depending on how familiar goats were with the learning task. We found a significant influence of the task and the interaction between task and time within the task on HRV parameters, indicating changes of vagal activity at the heart. The results suggest that changes in HR related to learning were predominantly caused by a withdrawal of vagal activity at the heart. With regard to nonlinear processes in heartbeat regulation, increased deterministic shares of HRV indicated that the animals did not really relax until the end of T3. Comparing changes of HR and HRV in T3 and in a subsequent postexperiment (PE), we assume a positive effect of such cognitive challenges once the task had been learned by the animals.

Animals↗
PubMed2006

Learning motion discrimination with suppressed and un-suppressed MT.

Perceptual learning of motion direction discrimination is generally thought to rely on the middle temporal area of the brain (MT/V5). A recent study investigating learning of motion discrimination when MT was psychophysically suppressed found that learning was possible with suppressed MT, but only when the task was sufficiently easy [Lu, H., Qian, N., Liu, Z. (2004). Learning motion discrimination with suppressed MT. Vision Research 44, 1817-1825]. We investigated whether this effect was indeed due to MT suppression or whether it could be explained by task difficulty alone. By comparing learning of motion discrimination when MT was suppressed vs. un-suppressed, at different task difficulties, we found that task difficulty alone could not explain the effects. At the highest difficulty, learning was not possible with suppressed MT, confirming [Lu, H., Qian, N., Liu, Z. (2004). Learning motion discrimination with suppressed MT. Vision Research 44, 1817-1825]. In comparison, learning was possible with un-suppressed MT at the same difficulty level. At the intermediate task difficulty, there was a clear learning disadvantage when MT was suppressed. Only for the easiest level of difficulty, did learning become equally possible for both suppressed and un-suppressed conditions. These findings suggest that MT plays an important role in learning to discriminate relatively fine differences in motion direction.

Discrimination, Psychological↗
PubMed1999

An evaluation of the concurrent discrimination task as a measure of habit learning: performance of amnesic subjects.

Habit learning has been defined as an association between a stimulus and a response that develops slowly and automatically through repeated reinforcement. Concurrent discrimination (CD) learning, in which subjects learn to choose the rewarded objects in a series of pairs, is believed to be an example of habit learning in monkeys. Studies of human amnesic subjects, however, have produced equivocal results, revealing impaired or absent learning on the same CD tasks that monkeys with medial temporal-lobe (MTL) lesions learn normally. One possible explanation for impaired performance in human amnesic subjects is that, unlike monkeys, human subjects use explicit memory to solve CD problems. To test this hypothesis, we administered a 10-object pair CD learning task to two amnesic subjects, HM and PN, and normal control subjects (NCS). Both amnesic subjects have severe anterograde amnesia with little ability to form explicit memories. On the CD task, they demonstrated little or no learning and acquired no explicit knowledge of the task procedures or reward contingencies. In contrast, NCS learned the task quickly and easily using explicit memory strategies. These results suggest that CD tasks cannot be learned by habit in human subjects, and emphasize the discrepancies between the human and monkey literature on habit learning.

Aged↗
PubMed1996

A relational view of learning: implications for nurse education.

For about two decades, student learning in the context of professional and higher education, more generally, has been investigated by groups of researchers in countries such as Sweden, the UK, Australia and South Africa. The focus in many of these studies has been on the experience of students as they undertake complex, realistic tasks such as reading academic articles, listening to lectures, writing essays, solving problems and learning subject matter concepts. Central to this research is the adoption of a relational and holistic model of learning in which the relationships among all elements in the learning situation, including the student, the learning task, the teaching methods and assessment practices have been investigated. In particular, researchers from this line of inquiry have studied the relationship between the ways students go about learning in natural educational settings, referred to as approaches to learning, and what they learn. They have established that a full understanding of subject matter is reliant on students employing deep learning approaches which, in turn, depend on the perceived learning environment encouraging such learning. In this paper, the work of the relational theorists is described and the substantial and practical findings arising from this school of research are reported. Specific implications for the education of undergraduate nurses are also outlined.

Clinical Competence↗
PubMed1999

Increased basal activity of the HPA axis and renin-angiotensin system in congenital learned helpless rats exposed to stress early in development.

Learned helpless behavior has been successfully bred in rats and designated as a genetic animal model of human depression and/or anxiety. Since congenital learned helpless animals have an impaired stress response in adulthood, we examined the effects of early stressors (at postnatal day 7, 14 or 21) on the hypothalamic-pituitary-adrenal axis and the renin-angiotensin system. The functioning of the hypothalamic-pituitary-adrenal axis was monitored through changes in corticosterone plasma levels in the adult animals after acute exposure to cold stress and maternal deprivation early in development. Renin-angiotensin system functioning was assessed by plasma renin activity. Unstressed congenital learned helpless rats had corticosterone levels that were similar to control animals (congenital non-learned helpless rats not stressed during development), but unstressed plasma renin activity levels of congenital learned helpless rats were lower than congenital non-learned helpless rats. There was a step-wise increase in corticosterone plasma levels in the congenital learned helpless rats with age of acute presentation of either cold stress or maternal deprivation stress (day 7, 49%; day 14, 84%; and day 21, 543% for cold stress). However, these baseline corticosterone levels were significantly lower in congenital learned helpless rats compared to congenital non-learned helpless controls. Similarly, in response to early exposure to cold stress and maternal deprivation, there was an increase in plasma renin activity levels of congenital learned helpless rats with age of presentation to either stressors. However, this increase in plasma renin activity levels was not evident in congenital non-learned helpless controls. Taken together, these results suggest that exposure to stress early in development has long-term effects on both the hypothalamic pituitary-adrenal axis and the renin-angiotensin system, two neuroendocrine indicators of stress responsivity.

Animals↗
PubMed1997

Abrupt learning and retinal size specificity in illusory-contour perception.

BACKGROUND: In behavioral studies of learning, a distinction is commonly made between gradual and abrupt improvements in performance. The learning of perceptual and motor skills is often characterized by gradual, incremental improvement, and is found not to generalize over stimulus manipulations such as changes in the size or location of the retinal image. In contrast, marked improvement in performance can occur suddenly - a phenomenon which has been termed 'insight'. Consequently, the brain mechanisms subserving the two types of learning are commonly thought of as distinct. Here, we examine learning of a perceptual task in which improvement appears to exhibit characteristics of both gradual and abrupt learning. RESULTS: We describe experiments on illusory-contour perception in which the observers underwent an abrupt, dramatic improvement in performance, resembling an incident of insight. At the same time, however, the phenomenon showed a degree of stimulus-specificity that was previously thought to characterize incremental, gradual learning. The improvement was triggered only by specific visual stimuli, whereas other, quite similar, stimuli were found to be ineffective for training; the learning did not generalize to a new retinal image size, and re-training was necessary for different-sized images. CONCLUSIONS: The juxtaposition of abrupt and stimulus-specific learning that we observed suggests that the distinction between the two forms of learning needs to be revised. Rather than postulating two distinct mechanisms, incremental and insightful learning need to be addressed within a single framework. In particular, the findings suggest that learning may involve interactions between multiple levels of representations of the stimulus.

Adolescent↗
PubMed1996

The PDSA cycle at the core of learning in health professions education.

BACKGROUND: The Plan-Do-Study-Act (PDSA) cycle lies at the heart of continuous improvement and is a redefinition of the scientific method for application to the world of work. HEALTH CARE AS A CONTEXT FOR HEALTH PROFESSIONS LEARNING: Educational institutions could create the best "quality learning" environments for students by relating closely to health care organizations that create improvement environments for workers. When both become "learning" organizations and develop a relationship with each other, an important product will be the integration of processes for individual and organizational learning. THE PDSA CYCLE AS LEARNING THEORY: The PDSA cycle can be an integrating theory for both individual and organizational learning. It shares basic features of well-accepted theory about individual and organizational learning, including the concepts of change and action/reflection. EVALUATING LEARNING THROUGH PDSA CYCLES: An illustration is given of one set of implications of the PDSA cycle as learning theory. It describes an alternative way of thinking about the evaluation of learning, which surpasses the traditional emphasis on judgment in evaluation. CONCLUSIONS: The potential to place the PDSA cycle at the core of learning in health professions education is great. Contributing factors to this potential include the historical emphasis on the scientific method in health care, the relationship between clinical education and practice, recent improvements in our capacity to define and measure health outcomes, emergent pressures for change in health care and education, and compatible multiple functions of the PDSA cycle.

Competency-Based Education↗
PubMed1996

Impaired incentive learning in treated Parkinson's disease.

OBJECTIVE: To quantify the performance of patients with Parkinson's disease (PD) in incentive learning, or learning to respond to stimuli that signal the imminent presentation of a reinforcer, and in paired-associate learning, or learning of word associations. METHODS: The performance of 32 patients with idiopathic PD was compared to that of 25 healthy control subjects, and 32 subjects suffering from arthritis, matched for age and education. The PD and arthritic groups were comparable on a self-report measure of physical disability. All subjects were physically capable of satisfying the contingencies of the incentive learning task. The avoidance task that quantified incentive learning used money loss as an aversive stimulus. The word paired-associate learning task was presented on a computer and feedback was not given on performance. RESULTS: The normal and arthritic groups performed equally well on the avoidance task, whereas the PD group was impaired despite dopaminergic replacement therapy. The groups did not differ significantly in paired-associate learning. CONCLUSIONS: These findings are among the first to suggest that the nigrostriatal dopamine dysfunction associated with PD may play a role in incentive learning but not in paired-associate learning and are consistent with a role for dopamine in certain forms of learning and memory. The findings may highlight differences between tonic and modulated function in the nigrostriatal system.

Aged↗
PubMed1987

Autonomy in children's learning: an experimental and individual difference investigation.

Ninety-one fifth-grade children participated in a study that assessed the effects of motivationally relevant conditions and individual differences on emotional experience and performance on a learning task. Two directed-learning conditions, one controlling and one noncontrolling, were contrasted with each other and with a third nondirected, spontaneous-learning context. Both directed sets resulted in greater rote learning compared with the nondirected-learning condition. However, both the nondirected and the noncontrolling directed-learning sets resulted in greater interest and conceptual learning compared with the controlling set, presumably because they were more conducive to autonomy or an internal perceived locus of causality. Furthermore, children in the controlling condition experienced more pressure and evidenced a greater deterioration in rote learning over an 8-(+/- 1) day follow-up. Individual differences in children's autonomy for school-related activities as measured by the Self-Regulation Questionnaire (Connell & Ryan, 1985) also related to outcomes, with more self-determined styles predicting greater conceptual learning. Results are discussed in terms of the role of autonomy in learning and development and the issue of directed versus nondirected learning.

Child↗
PubMed1984

Paired-associate learning and priming effects in amnesia: a neuropsychological study.

Despite severe deficits of recall and recognition, amnesic patients can exhibit normal priming effects. Amnesic patients have also been reported to perform well on tests of paired-associate learning that involve related word pairs (e.g., table-chair). The present study investigated the role of priming effects in paired-associate learning. Experiment 1 illustrated the distinction between the memory impairment of amnesic patients and their intact priming ability. Amnesic patients were markedly deficient in learning unrelated word pairs, despite exhibiting normal priming as measured by a word-completion test involving the same words. In Experiment 2A, amnesic patients showed good paired-associate learning for related word pairs, though control subjects still performed significantly better. In addition, the good performance by amnesic patients was short-lived, and performance fell to baseline after a 2-hr delay. Control subjects performed well above baseline at all delay conditions. Experiment 2B showed that the forgetting of related word pairs by amnesic patients followed the same time course as the decay of word priming. Experiment 3 showed that amnesic patients were as good as control subjects at learning related word pairs when incidental learning and test procedures were used (a word-association test). The advantage of control subjects over amnesic patients in Experiments 2A and 2B could therefore be attributed to the explicit learning instructions that are standard in paired-associate tests. Finally, Experiment 4 showed that amnesic patients exhibited normal priming when they were asked to "free associate" to words (e.g., child) that were semantically related to previously presented words (e.g., baby). The results indicate that both priming effects and paired-associate learning of related word pairs depend on activation, a process that is preserved in amnesia. Activation can account for the findings of good performance by amnesic patients on tests of word priming (Experiments 1 and 2B), related paired associates (Experiments 2A and 2B), and word association (Experiments 3 and 4). Activation is a transient phenomenon presumed to operate on and facilitate access to preexisting representations. Control subjects can establish new associations and can strengthen preexisting associations by engaging processes that are impaired in amnesia. As a result, when explicit learning instructions are used to test paired-associate learning of related word pairs, control subjects can learn better and can remember longer than can amnesic patients (Experiments 2A and 2B).(ABSTRACT TRUNCATED AT 400 WORDS)

Alcohol Amnestic Disorder↗