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PubMed2004

Relations between Pavlovian-instrumental transfer and reinforcer devaluation.

Relations between posttraining reinforcer devaluation and Pavlovian-instrumental transfer were examined in 2 experiments. When a single reinforcer was used, extended training of the instrumental response increased transfer but reduced devaluation effects. When multiple instrumental reinforcers were used, both reinforcer-specific transfer and devaluation effects were less influenced by the amount of instrumental training. Finally, although reinforcer devaluation decreased both Pavlovian conditioned responses and baseline instrumental responding, it had no effect on either single-reinforcer or reinforcer-specific transfer. These results indicate that transfer and reinforcer devaluation can reflect different aspects of associative learning and that the nature of associative learning can be influenced by parameters such as the amount of training and the use of multiple reinforcers.

Analysis of Variance↗
PubMed1983

Haptic attention and visual transfer by mentally retarded and nonretarded individuals.

Four mentally retarded and four nonretarded adolescents learned compound discriminations in the haptic (touch) modality using Ray's (1969) conflict-compound procedure. Reinforcement history was controlled so that prior reinforcement contingencies were unchanged for one element and reversed for the other element of a compound (two-element) stimulus during discrimination training. Consistent with Huguenin and Touchette's (1980) results in the visual modality, our retarded subjects evinced selective attention effects in posttraining tests conducted in the haptic modality. Results with nonretarded subjects similarly indicated that they had selectively attended to only one element of a conflict-compound stimulus during compound discrimination training. Visual transfer tests revealed that for most individuals the effects of conflict-compound discrimination training transferred from the haptic to visual sensory modalities. Results were discussed in terms of selectivity of attention to nonredundant stimulus elements as an effective strategy for discrimination learning rather than a perceptual deficit.

Adolescent↗
PubMed1990

Crossmodal short-term memory of haptic and visual information.

Rhesus monkeys were trained on a within-subjects design to assess whether they could perform concurrently visual-to-haptic (V-H) and haptic-to-visual (H-V) crossmodal delayed matching-to-sample (DMS). A parametric analysis was conducted of the effect of delay between presentation and re-presentation of the test discriminanda (three-dimensional geometric objects). The results indicate that (a) monkeys are capable of concurrent V-H and H-V crossmodal matching of objects by shape, size, and texture; (b) monkeys acquire faster and perform better crossmodal matching in the V-H direction than in the H-V direction; (c) as they learn to perform DMS with successive object pairs, monkeys transfer some--procedural--knowledge from the use of one pair to the use of the next; and (d) in the monkey, crossmodal short-term memory, as measured by DMS performance, has a temporal decline.

Animals↗
PubMed2003

Generalization of object manipulation skills learned without limb motion.

Recent work suggests that human subjects may learn mappings between object motion and exerted torque during manipulation of freely pivoting or unstable objects. In the present work, we studied an object manipulation task involving no arm movement to determine how subjects internally represent the force-motion relationship of an object during a skilled manipulation task. Human subjects learned to balance a simulated inverted pendulum. The simulation was controlled by pressing on a fixed force sensor, and applied forces resulted in motion of the simulated pendulum on a computer screen according to its equation of motion. Each subject initially learned the task in one arm posture and was tested 1 d later in a new arm posture. In one test condition, the effects of arm torque were matched to the original task, and in the other test condition, the simulation was unchanged. The pattern of skill transfer to different arm postures suggested that subjects had learned joint torque responses rather than a general model of the object interface forces. A second experiment showed that the advantage of training with matched arm torques was object specific, because torque-matched training on a tracking task involving similar forces was not a substitute for training in the balancing task.

Adult↗
PubMed1980

Transfer of information with brain extracts from donors to recipients in passive-avoidance behavior.

Experiments were conducted in a step-through, one-trail, passive-avoidance situation, in order to study the effect of crude or 10,000 dalton-ultrafiltered brain extracts, from trained donor rats, on the learning of the same behavior in naive or undertrained recipient rats. A positive transfer effect was consistently detectable in the latter, apparently related to consolidated learning, but not to the level of avoidance performance or of general activation in the donors. Temporal and cognitive requirements, for such an effect to occur, have been established with regard to donor-training and recipient-managing procedures. A tentative explanation of the transfer effect in the passive-avoidance behavior cannot disregard the possibility of material transmission of information pertaining to a response elicited by primary or secondary reinforcement. Such a response, although quite distinct from the somatomotor response, would be necessary to its acquisition but not to its expression.

Animals↗
PubMed2002

Hippocampus-dependent retrieval and hippocampus-independent extinction of place avoidance navigation, and stress-induced out-of-context activation of a memory revealed by reversible lesion experiments in rats.

The use of reversible lesion techniques in memory research was pioneered in the laboratory of Jan Bures and Olga Buresova. We use the occasion of Jan's 75th birthday to briefly review the experimental utility of this approach. Two experiments from our current research are reported in which reversible lesioning methods are used to ask otherwise experimentally untenable questions about memory retrieval. The first experiment used intra-hippocampal injections of tetrodotoxin to temporarily inactivate the hippocampus during retrieval of a well-learned place avoidance navigation memory. This revealed that the hippocampus is necessary for place avoidance retrieval but that the extinction of place avoidance can occur independently of retrieving the memory and intact hippocampal function. The second experiment used KCl-induced cortical spreading depression in an interhippocampal transfer paradigm to demonstrate that a Y-maze memory that is learned by only one cortical hemisphere can be made to transfer to the other hemisphere by forcing the rat to swim, a unique stressful experience that occurred in a different apparatus, different behavioral context, and involved different behaviors than the Y-maze training. This demonstrates, we believe for the first time behaviorally, that memories can be activated outside of the behavioral context of their acquisition and expression in rats.

Animals↗
PubMed2001

Neurogranin null mutant mice display performance deficits on spatial learning tasks with anxiety related components.

Neurogranin/RC3 is a protein that binds calmodulin and serves as a substrate for protein kinase C. Neuronally distributed in the hippocampus and forebrain, neurogranin is highly expressed in dendritic spines of hippocampal pyramidal cells, implicating this protein in long-term potentiation and in learning and memory processes. Null mutation of the neurogranin gene Ng generated viable knockout mice for analysis of the behavioral phenotype resulting from the absence of neurogranin protein. Ng -/- mice were normal on measures of general health, neurological reflexes, sensory abilities, and motor functions, as compared to wild type littermate controls. On the Morris water task, Ng -/- mice failed to reach acquisition criterion on the hidden platform test and did not show selective search on the probe trial. In the Barnes circular maze, another test for spatial navigation learning, Ng -/- mice showed impairments on some components of transfer, but normal performance on time spent around the target hole. Abnormal and idiosyncratic behaviors were detected, that appeared to represent an anxiogenic phenotype in Ng -/- mice, as measured in the light<-->dark exploration test and the open field center time parameter. These findings of apparent deficits in spatial learning and anxiety-like tendencies in Ng -/- support a role for neurogranin in the hippocampally-mediated interaction between stress and performance.

Animals↗
PubMed1994

Interhippocampal transfer of place navigation monocularly acquired by rats during unilateral functional ablation of the dorsal hippocampus and visual cortex with lidocaine.

To study the neural mechanisms of interhippocampal transfer of lateralized place navigation engrams in rats, lidocaine was injected via chronically implanted cannulae to reversibly inactivate the hippocampal formation and the visual cortex on one side. The eye opposite the blocked side was occluded. Under these conditions, rats learned the location of an invisible platform in a water maze [mean escape latencies per four-trial block (t) = 5-6 s at the performance asymptote]. Monocular intact brain retrieval with the trained eye (t = 7) was better than with the untrained eye (t = 13). However, analysis of each retrieval trial indicated untrained eye performance was only poor on the first trial (t = 30). To test whether trans-commissural read-out alone or write-in (i.e. interhippocampal transfer) of the lateralized engram explains the above results, rats acquired a new platform location (t = 5). Two groups were then given a 30-s "free swim" (the platform was removed) with intact brain and either the trained or untrained eye occluded. A third group did not have this "transfer" trial. Retrieval was tested with the trained hippocampus and visual cortex blocked. With the trained eye occluded, retrieval in the rats that had the transfer trial (t = 11) was better than in those that did not (t = 25), but slightly worse than in rats tested with the untrained eye, hippocampus and visual cortex blocked (t = 7). Additionally, retrieval was similar, independent of whether the trained (t = 12) or untrained (t = 11) eye was open on the transfer swim. The 30-s swim alone did not induce comparable savings. We conclude that interhippocampal transfer of lateralized place learning is easily induced, is equal if the transfer is facultative or imperative, and involves both trans-commissural read-out and write-in processes.

Animals↗
PubMed1993

The role of the amygdala and dorsal raphe nucleus in mediating the behavioral consequences of inescapable shock.

It has been argued that exposure to inescapable shock produces later behavioral changes such as poor shuttle box escape learning because it leads to the conditioning of intense fear, which later transfers to the shuttle box test situation and interferes with escape. Both fear, as assessed by freezing, and escape were measured in Sprague-Dawley rats 24 hr after exposure to inescapable shock. Lesions of the basolateral region and central nucleus of the amygdala eliminated the fear that transfers to the shuttle box after inescapable shock, as well as the fear conditioned in the shuttle box by the shuttle box shocks. However, the amygdala lesions did not reduce the escape learning deficit produced by inescapable shock. In contrast, dorsal raphe nucleus lesions did not reduce the fear that transfers to the shuttle box after inescapable shock, but eliminated the enhanced fear conditioning in the shuttle box as well as the escape deficit. The implications of these results for the role of fear and anxiety in mediating inescapable shock effects are discussed.

Amygdala↗
PubMed1990

Learning caring behavior in an integrated manner.

We can see that by transferring caring behaviors from previous experiences, by imitation of role models, and by multiple experiential activities, learners form and utilize schemata of caring. By finding ways to stimulate learners to think about the feeling of caring and to imagine caring for others, caring becomes a psychophysiological or psychokinesthetic experience. A broad aim or high-level purpose, that is, to care, to have interest in and concern for others, or union and separation toward growth could serve as an inner context that would automatically evoke associated networks of learned, integrated caring actions. The caregiver would not usually be aware of each separate action. These broad aims would organize procedural knowledge, or "know how," in the motor areas of the brain. Let us return to Gardield's predicament. Can we help him walk again? Perhaps someone will call him in a friendly voice, someone whom he knows will give him a little chow and lots of stroking on his head. I suspect he would forget about his feet and just hurry over.

Awareness↗
PubMedDate not supplied

Cross modal transfer of a conditional flexion response in dogs.

Two experiments investigated cross modal transfer of a conditional flexion response. In the first experiment, two dogs with extensive experimental past histories transferred a discrimination based on the pattern of presentation of auditory stimuli to a comparable pattern of visual stimuli. A second experiment with a naive dog demonstrated that such stimulus patterning also occurred from visual to auditory modalities. Additional tests showed that transfer was based on the relationship between discriminative stimuli and that the negative stimulus in the second modality was actively inhibitory. The data were discussed with reference to general attentiveness and rudimentary concept learning.

Animals↗
PubMed1991

Impairment of olfactory, auditory, and spatial serial reversal learning in rats recovered from pyrithiamine-induced thiamine deficiency.

Rats that had recovered from pyrithiamine-induced thiamine deficiency (PTD) were compared with controls for spatial, auditory, and olfactory serial reversal learning (SRL); spatial matching to sample (MTS); auditory go-no-go discrimination; and open-field exploration. PTD rats made more errors reaching criterion for SRL in all modalities but showed normal transfer effects between problems. PTD rats were also impaired in learning the go-no-go and MTS tasks and showed consistent alterations in exploratory activity. It is argued that the PTD rat, like human Korsakoff patients, have impairments of learning and memory (but spared capacity for reference memory) that extend across sensory modalities. Postmortem analyses showed normal indices of cortical cholinergic, noradrenergic, dopaminergic, and serotonergic function and consistent bilateral lesions of the thalamus, which were centered on the internal medullary lamina, and the medial mammillary nucleus.

Animals↗
PubMed1982

Improving the visual discrimination of mentally retarded children: a training strategy.

Mentally retarded children were asked to judge whether a series of visual stimuli matched a standard. With each judgment the investigator verbalized "right" or "wrong" and then provided full feedback of particulars, indicating with gesture and words the cue similarities and differences that supported each correct and each incorrect judgment. Control subjects were either given no training (test--retest only) or were asked to make the judgments but given no feedback. Attesting to the efficacy of the training procedure, the trained subjects exhibited total intradimensional transfer; the control subjects, none. The results were related to the attention-retention theory of discrimination learning developed by Fisher and Zeaman and to the "differentiation" methodology and theory presented by Gibson and Gibson.

Adolescent↗
PubMed1993

The changing role of volunteerism.

As the number of Americans who volunteer grows, the definition of "volunteer" is becoming more broad. In addition to the traditional volunteer opportunity, there are community service, student internship, and court-ordered service programs, all of which pose a set of complicated managerial questions for those charged with designing and running volunteer programs. Today, volunteers' motives may extend further than the simple desire to help their neighbor. For example, given the tough job market, some individuals are volunteering as a possible bridge to employment, and are eager to learn skills and gain experience that they might transfer to a new work setting. The growth in the number of volunteers is not without its down side, however. As governments have cut back on service programs, some responsibilities traditionally assumed by government are being shunted to volunteer organizations, an inappropriate solution. Although volunteer programs deserve support, governments cannot be let off the hook. Volunteers cannot and should not replace paid staff. There are a number of exciting and innovative approaches to recruiting, managing, and motivating volunteers. Some programs are responding to the new kinds of volunteers by restructuring the volunteer opportunity to make it more accessible to those who work from 9 to 5. Others are responding to the diversity of the communities they serve by seeking training in cultural sensitivity and recruiting volunteers from the community. Whatever the volunteer opportunity, the screening and placement interview is a crucial first step. It should be used to clarify expectations--of the volunteer and of the volunteer administrator. Once volunteers are on board, the key to managing and retaining volunteers is to recognize what motivates the individual volunteer--whether it is the desire to acquire job-related skills, to socialize, or simply to learn new things--and to provide the volunteer with these opportunities. Continuing education, training, and feedback are essential ingredients of any volunteer program. Another key to retaining volunteers is appropriate recognition. Although volunteers may appreciate the traditional pin or letter of thanks, volunteer administrators should explore other means of recognition that are tied in to the individual volunteer's motives for volunteering in the first place. Involving volunteers in the development and refinement of the volunteer program and considering their suggestions for improvements are important ways of keeping them involved and signaling recognition of their expertise and value.(ABSTRACT TRUNCATED AT 400 WORDS)

Acquired Immunodeficiency Syndrome↗
PubMed2005

Skill training, retention, and transfer: the effects of a concurrent secondary task.

In two experiments, we examined training, retention, and transfer of a duration production skill in a prospective paradigm. Participants were trained with feedback and then were either tested immediately for transfer without feedback or retrained with feedback 1 week later. There were three training and retraining conditions, two involving secondary tasks. Retention of the duration production skill was perfect across the 1-week delay when the secondary task condition was unchanged, but there was no skill transfer when that condition was changed. These findings demonstrate specificity of training, with the assumption that the cognitive operations learned during duration production training incorporate requirements of the secondary task. More generally, this study challenges the current practice in which training conditions often do not match eventual testing conditions.

Adult↗