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Effects of ECT-dothiepin combination on learning in rats.

Electroconvulsive therapy (ECT) and antidepressant drugs are each known to impair learning and memory. No information is available on their effects on cognition when used concurrently in the treatment of depression, as is frequent in India. In the present study, therefore, the effects of electro-convulsive shocks (ECS) and dothiepin, separately and in combination, were studied in an animal model employing a complex maze operant learning paradigm. ECS were given on alternate days (3/week) for 2 weeks. Dothiepin (10 mg/kg, ip) was administered once daily for 2 weeks. Learning was assessed on days 2-10 post-treatment ECS produced greater initial impairment in learning while dothiepin produced a more sustained impairment. While impairment was maximum in the combined treatment group, the statistical significances that emerged to proscribed the combination were but weak.

Animals↗

Halo and devil effects demonstrate valenced-based influences on source-monitoring decisions.

Source attributions based on positive versus negative valence were examined in four experiments. The two sources were individuals who were depicted positively or negatively, and the content of their statements was similarly valenced. When valenced information about the sources was provided after learning the statements, test biases to attribute positive statements to the positive source and negative statements to the negative source were strongly present. Providing the same information prior to learning improved memory, but did not entirely eliminate test biases based on valence. Signal detection analysis suggests that these "halo effect" biases are criterion-based and not memory-based. Therefore, the results are more consistent with descriptions of source-monitoring processes that can benefit from familiarity-based partial information as opposed to descriptions in which source monitoring is primarily recollection-based.

Adolescent↗

The evaluative response: primitive but necessary.

We do not believe the claim that "evaluative conditioning is a qualitatively distinct form of classical conditioning" [Davey (1994). Behaviour Research and Therapy, 32, 291-299]. We view all classical conditioning as a learning process which leads organisms to assign a positive or negative value to previously neutral stimuli and to respond to them accordingly. The evaluative response is a necessary component of this process and hence it is central to all classical conditioning, not a separate type. Davey concentrates on a signal-based information processing view of learning, i.e. the formation of linear associations between CS and UCS of which human subjects are aware and which they can verbalize. We propose a more primitive and more general model in which stimulus evaluation (like/dislike) occurs with a minimal degree of processing, and enters into a representation of stimulus (CS and UCS) and response (CR and UCR) characteristics which is reintegrative rather than associative.

Animals↗

Intentional forgetting as a facilitator for recalling new product attributes.

When market changes alter what product attributes are deemed important, consumers may intentionally try to forget old product information in an attempt to remember new product information. In Experiment 1, the authors demonstrated that intentional forgetting of this nature temporarily inhibits retrieval of old product information and leads to a benefit to memory for new product information. The results show that, after a short delay, benefits continue in the absence of costs, which is supportive of a multiple-process account of intentional forgetting. Experiment 2 extends these effects using an advertising message to stimulate forgetting. Across both experiments, results also show that brand preference is based on learning of new attribute information.

Adolescent↗

Infant motor development is associated with adult cognitive categorisation in a longitudinal birth cohort study.

BACKGROUND: The relationship between the age of reaching infant developmental milestones and later intellectual function within the normal population remains unresolved. We hypothesised that the age of learning to stand in infancy would be associated with adult executive function and that the association would be apparent throughout the range of abilities, rather than confined to extremes. METHODS: The Northern Finland 1966 Birth Cohort is based upon 12,058 live-born children in a geographic and temporally defined population. Information on age at learning to stand without support was obtained at one year. At age 33-35 a random sample of 104 subjects underwent a neuropsychological test battery including tests of executive function (cognitive categorisation), visuo-spatial memory, verbal learning and visual object learning. We investigated associations between developmental data and adult neuropsychological test scores. RESULTS: There was a significant linear relationship between age of learning to stand and adult categorisation: the earlier the attainment of the milestone, the better was the categorisation. No such relationships were observed between infant neurodevelopment and adult cognition in other neuropsychological domains. CONCLUSION: Even within the normal range of development, early development in the gross motor domain is associated with better adult executive function (in tests of categorisation). Investigation of the determinants and sequelae of normal neural development will facilitate research into a variety of neurodevelopmental disorders.

Adult↗

Distributed model of collicular and cerebellar function during saccades.

How does the brain tell the eye where to go? Classical models of rapid eye movements are lumped control systems that compute analogs of physical signals such as desired eye displacement, instantaneous error, and motor drive. Components of these lumped models do not correspond well with anatomical and physiological data. We have developed a more brain-like, distributed model (called a neuromimetic model), in which the superior colliculus (SC) and cerebellum (CB) play novel roles, using information about the desired target and the movement context to generate saccades. It suggests that the SC is neither sensory nor motor; rather it encodes the desired sensory consequence of the saccade in retinotopic coordinates. It also suggests a non-computational scheme for motor control by the cerebellum, based on context learning and a novel spatial mechanism, the pilot map. The CB learns to use contextual information to initialize the pilot signal that will guide the saccade to its goal. The CB monitors feedback information to steer and stop the saccade, and thus replaces the classical notion of a displacement integrator. One consequence of this model is that no desired eye movement signal is encoded explicitly in the brain; rather it is distributed across activity in both the SC and CB. Another is that the transformation from spatially coded sensory information to temporally coded motor information is implicit in the velocity feedback loop around the CB. No explicit spatial-to-temporal transformation with a normalization step is needed.

Cerebellum↗

Minor physical anomalies: relation to later achievement.

A substantial number of school-age children with learning disability are characterized as being distractible, and there is a congenital contributor to distractibility that has shown relation to school achievement, and to learning disability in particular. This congenital contributor can be assessed at any time from the neonatal through the early school-age period by a 10-minute examination. It seems likely that the basis for the congenital contributor to learning disability is an information processing defect that appears as early as the first year of life in the form of a rapid waning of attention when tired, an overly slow waning when in a rested state, and a failure to form cognitive schemas from perceptual input in either case. The congenital characteristic could also affect learning disability by its association with less than optimal peer relations. The latter could, in turn, affect the child's link to the classroom learning situation.

Achievement↗

c-fos is induced in the hippocampus during consolidation of sexual imprinting in the zebra finch (Taeniopygia guttata).

c-fos was used to mark regions of enhanced neuronal activity during sexual imprinting, an early learning process by which information about the prospective sexual partner is acquired and consolidated. In the present study, we demonstrate that the hippocampus, already known for its specialized spatial memory capacities in navigating pigeons and in food-storing birds, depicts a selective differential c-fos induction in a situation shown to lead to sexual imprinting, that is, exposing previously isolated male birds to a female for 1 h. c-fos induction is lateralized, the left hippocampus showing more c-fos activity than the right. Our results would indicate a role for the hippocampus in the consolidation process of imprinting, probably in the transfer of information to the other telencephalic areas that show alterations in synaptic connectivity as a result of consolidation of sexual imprinting.

Animals↗

Amygdalo-hypothalamic circuit allows learned cues to override satiety and promote eating.

Organisms eat not only in a response to signals related to energy balance. Eating also occurs in response to "extrinsic," or environmental, signals, including learned cues. Such cues can modify feeding based on motivational value acquired through association with either rewarding or aversive events. We provide evidence that a specific brain system, involving connections between basolateral amygdala and the lateral hypothalamus, is crucial for allowing learned cues (signals that were paired with food delivery when the animal was hungry) to override satiety and promote eating in sated rats. In an assessment of second-order conditioning, we also found that disconnection of this circuitry had no effect on the ability of a conditioned cue to support new learning. Knowledge about neural systems through which food-associated cues specifically control feeding behavior provides a defined model for the study of learning that may be informative for understanding mechanisms that contribute to eating disorders and more moderate forms of overeating.

Acoustic Stimulation↗

People want to see information that will help them make valid inferences in human causal learning.

According to higher order reasoning accounts of human causal learning (e.g., Lovibond, Been, Mitchell, Bouton, and Frohardt, 2003; Waldmann and Walker, 2005) ceiling effects in forward blocking (i.e., smaller blocking effects when the outcome occurs with a maximal intensity on A+ and AX+ trials) are due to the fact that people are uncertain about the causal status of a blocked cue X in a forward blocking design when the outcome is always fully present on A+ and AX+ trials. This should not be the case for a reduced overshadowing cue Y (B- trials followed by BY+ trials). We tested this hypothesis by asking participants which additional information they preferred to see after seeing all learning trials. Results showed (1) that all participants preferred to see the effect of the blocked cue X over seeing the effect of the reduced overshadowing cue Y (Experiment 1), and (2) that more participants preferred to see the blocked cue X on its own when the outcome on A+ and AX+ trials was fully present than when the outcome on those trials had a submaximalintensity (Experiment 2).

Association Learning↗

The human gynome.

This year marks the 50th anniversary of the identification of the 3-dimensional structure of the DNA double helix and the completion of the US Human Genome Project. Now that we have completed the human genome sequence, what have we learned? How will this information benefit humankind? And, what are the implications for our patients in obstetrics and gynecology? Perhaps the biggest surprise is that there are only approximately 30,000 human genes, far fewer than earlier estimated. I propose the term "gynome" to describe that part of the human genome that is unique to women. We have learned that manifestations of diseases and therapeutic response can be gender specific. A major challenge is to define the interplay of the genetic variations of women with variations in their environment and lifestyle. Ultimately, this should lead to improved diagnosis of disease, earlier detection of genetic predispositions to disease, the design of more effective drugs, and gene therapy.

Female↗

Comparison of relevance learning vector quantization with other metric adaptive classification methods.

The paper deals with the concept of relevance learning in learning vector quantization and classification. Recent machine learning approaches with the ability of metric adaptation but based on different concepts are considered in comparison to variants of relevance learning vector quantization. We compare these methods with respect to their theoretical motivation and we demonstrate the differences of their behavior for several real world data sets.

Artificial Intelligence↗

Listening experience with iterated rippled noise alters the perception of 'pitch' strength of complex sounds in the chinchilla.

Behavioral responses obtained from chinchillas trained to discriminate a cosine-phase harmonic tone complex from wideband noise indicate that the perception of 'pitch' strength in chinchillas is largely influenced by periodicity information in the stimulus envelope. The perception of 'pitch' strength was examined in chinchillas in a stimulus generalization paradigm after animals had been retrained to discriminate infinitely iterated rippled noise from wideband noise. Retrained chinchillas gave larger behavioral responses to test stimuli having strong fine structure periodicity, but weak envelope periodicity. That is, chinchillas learn to use the information in the fine structure and consequently, their perception of 'pitch' strength is altered. Behavioral responses to rippled noises having similar periodicity strengths, but large spectral differences were also tested. Responses to these rippled noises were similar, suggesting a temporal analysis can be used to account for the behavior. Animals were then retested using the cosine-phase harmonic tone complex as the expected signal stimulus. Generalization gradients returned to those obtained originally in the naïve condition, suggesting that chinchillas do not remain "fine structure listeners," but rather revert back to being "envelope listeners" when the periodicity strength in the envelope of the expected stimulus is high.

Acoustic Stimulation↗

Mental models and meaningful learning.

If you understand something, you can use the information you have acquired to solve problems to which that knowledge is relevant. Meaningful learning is learning with understanding. Achieving meaningful learning begins with the building of correct, appropriate mental models, or representations, of the knowledge being acquired. The next step is learning to use the available mental models to solve problems. In many of the biomedical sciences, this means being able to either calculate something, predict the responses of the system, or explain the responses of the system. Since only the learner can do the learning, the only possible role for the teacher is to help the learner to learn. This means creating an active learning environment in which the learner can acquire the needed information, continually test the mental models being built, and correct or refine those models as needed. In an active learning environment, students are given ample opportunities to learn to solve problems. If the goal of the course is the achievement of meaningful learning, it is essential that the students then be assessed to determined whether they have reached that goal.

Animals↗

Cognitive deficit associated with cholinergic and nerve growth factor down-regulation in experimental allergic encephalomyelitis in rats.

Clinical symptoms in multiple sclerosis include cognitive dysfunction. Difficulties in learning and remembering new information represent the most common cognitive deficit and are associated with a general and progressive brain pathology. Possible pathogenetic mechanisms for neuronal damage such as neuroprotective strategies are under active investigation also in experimental allergic encephalomyelitis, the most widely used experimental model for multiple sclerosis. In this paper we demonstrate that a selective deficit in learning and memory performance, as investigated by the Morris water maze test, is a consistent feature in rat encephalomyelitis, which correlates with a decline in choline acetyltransferase activity and nerve growth factor mRNA level in cerebral cortex, hippocampus, and basal forebrain. Treatment aimed to restore acetylcholine content through chronic administration of selective acetylcholinesterase inhibitors (rivastigmine and donepezil) restores cognitive performance, choline acetyltransferase activity, and nerve growth factor mRNA expression.

Animals↗

Pallidotomy and incidental sequence learning in Parkinson's disease.

Converging evidence from animal research and human brain imaging studies, points to an important role of cortical-striatal motor circuitry in the incidental learning of serial order information. To date, attempts to address this role through the study of patients with striatal disorder have proved inconclusive. The present study examined the impact of a therapeutic lesion of the globus pallidus in patients with Parkinson's disease. The lesion, which blocks a primary output of the putamen to the motor cortices, eliminated incidental learning relative both to controls and unoperated patients. The finding offers support for models proposing that context detection within the striatum is a central process in serial order learning. An unexpected effect of the lesion was to significantly reduce the response time to random stimuli relative to an ordered series, the opposite of the normal pattern. It is speculated that this may reflect an unconscious alerting response to novelty, a process suggested to involve the ventral striatum and its cortical targets. Research on Parkinson's disease patients undergoing functional basal ganglia surgery may shed further light on the mechanisms and neuronal substrate of serial order learning in humans.

Aged↗

A more biologically plausible learning rule for neural networks.

Many recent studies have used artificial neural network algorithms to model how the brain might process information. However, back-propagation learning, the method that is generally used to train these networks, is distinctly "unbiological." We describe here a more biologically plausible learning rule, using reinforcement learning, which we have applied to the problem of how area 7a in the posterior parietal cortex of monkeys might represent visual space in head-centered coordinates. The network behaves similarly to networks trained by using back-propagation and to neurons recorded in area 7a. These results show that a neural network does not require back propagation to acquire biologically interesting properties.

Animals↗

Nursing education in crisis: a computer alternative.

The impact of computer-assisted instruction upon the educational process is having its effect. The computer is being used in nursing education today to manage the educational environment, to instruct, to evaluate, to identify problem areas, to gather data, to manipulate data for research purposes and for continued education. As we struggle in our efforts for quality individualized education, we are minutely scrutinizing every aspect of the teaching learning process. We are not only examining how we teach but what we teach and why we are teaching it! Our deeper understanding of the process of education has helped us to delineate nursing process as content. Higher levels of instructional goals -- cognitive, affective and conative -- are resulting in education of the whole individual. The systematization of the learning process with the greater ease of accountability is leading nursing education to blaze promising new trails into the twenty-first century.

Computer-Assisted Instruction↗