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The role of tone height, melodic contour, and tone chroma in melody recognition.

The present experiments assessed the contribution of tone height, melodic contour, and tone chroma to melody recognition. Rather than using highly familiar folk songs as in earlier studies, subjects were taught new melodies. Novel melodies were used to (a) more precisely control potential cues (e.g., rhythm) that are not of present interest, (b) eliminate unison intervals that cannot be transformed appropriately, (c) provide a direct analysis of the nature of confusion errors, (d) test whether recently learned melodies are recognized differently than highly overlearned melodies, and (e) evaluate the extent to which practice in the experimental task alters the process of recognition. The results replicate previous studies using familiar folk songs. Transformations of the original melodies were accurately recognized when tone height was violated, but both melodic contour and tone chroma were maintained. Violating both tone height and contour while maintaining chroma produced extremely poor recognition. Performance was intermediate when just melodic contour was preserved. There is now good evidence to support the idea that melodic contour and tone chroma, in addition to tone height, contribute to recognition of both highly familiar and recently learned melodies.

Humans

Mental acuity of the normal elderly.

The elderly are persons over age 65, now comprising 12% of our population. The normal elderly function normally both in their self care, and also in their social activities of daily living, which we tabulate. The current terms for the normally functioning elderly who show only mild psychological deficits are age-associated memory impairment and age-related cognitive decline, which we define, criticize and tabulate. The psychological deficits of the elderly consist of mild generalized slowing and inaccuracies compared to normal young persons. These deficits are measured by objective psychological tests which mimic real daily living situations--the name-face test, fire alarm test, two delayed recall tests, misplaced objects test, shopping list test, and digit symbol test, which we describe. A longer early formal education is preventive of mental dulling during normal aging. Treating using overlearning, by cognitive training, is significantly beneficial.

Activities of Daily Living

The effect of visual deprivation in the rat on transfer effects after form discrimination training.

In 3 experiments the performances of light-reared (LR) and dark-reared (DR) 90-day-old rats were compared on a variety of transfer tests following acquisition of 3 discriminations involving patterns of small squares (dots). Though no significant difference due to rearing condition was found in acquisition of those discriminations consisting of single lines of dots in various orientations, transfer tests did reveal subtle differences in the way LR and DR rats analyze contour information. Significant differences due to rearing were also observed on the acquisition of a complex dot pattern (gradient vs X) and, in spite of overtraining, on subsequent stimulus equivalence tests. Anomalous transfer effects were not observed in any of these test situations.

Animals

Associative recall and formation of stable modes of activity in neural network models.

Models of neural networks with recurrent inhibition are studied, as well as one model which also includes recurrent excitation. The models are intended as possible descriptions of the cerebral cortex. Each network model is composed of neuron models called pyramidal cells and stellate cells in accordance with the names of two types of cells in the cortex. Inputs and outputs of the network are connected to the pyramidal cells while feedback is provided by the stellate cells. Connections within the network are random. During a learning phase the pyramidal cell excitatory synapses become facilitated according to a two-conditional facilitation rule. This is the basis of the model's ability for associative learning. The associative retrieval of information can be studied during a subsequent association phase. This has been done by simulation on a digital computer. It was shown that all of the models considered can be designed to perform a so-called decision-making function. This means that if the associating input pattern is similar to several patterns which occurred during learning the model can decide which similarity is greatest by responding with the appropriate associated pattern. The model also including recurrent excitation differs from the simpler models in that it can become stabilized in so-called stable modes of activity which are self-sustaining and remain even after the input has been turned off. Normally, only one stable mode can be active at a time. However, through careful choice of construction parameters it was possible to obtain a model in which a maximum of two stable modes could be activated independently of each other. Physiological and psychological interpretations are discussed and so are the limitations of the models, which are evident in certain situations.

Cerebral Cortex

Piracetam-induced facilitation of interhemispheric transfer of visual information in rats.

The effect of Piracetam (UCB 6215, 2-pyrrolidoneacetamide) on learning mediated by transcommissural information flow was studied in hooded rats. Acquisition of monocular pattern discrimination was faster in drug-treated rats (100 mg/kg, 30 min before training) than in untreated controls. Subsequent relearning with one hemisphere functionally eliminated by cortical spreading depression showed that the strength of the primary engram formed under Piracetam in the hemisphere contralateral to the trained eye remained unaffected but that the secondary trace (in the ipsilateral hemisphere) was considerably improved and almost equalled the primary one (savings increased from 20-30% to 50-60%). Learning with uncrossed optic fibers was unaffected by the drug. Interhemispheric transfer of lateralized visual engrams acquired during functional hemidecortication was facilitated by Piracetam administration preceding the five transfer trials performed with the untrained eye open (imperative transfer). Piracetam was ineffective when the trained eye was open during transfer trials (facultative transfer). After a visual engram had been lateralized by 5 days of monocular overtraining, Piracetam facilitated formation of the secondary engram induced by 3 interocular transfer trials. It is concluded that Piracetam enhances transcommissural encoding mechanisms activated in the initial stage of monocular learning and in some forms of interhemispheric transfer, but does not affect the transcommissural readout. This effect is interpreted as a special case of the Piracetam-induced facilitation of the phylogenetically old mechanisms of redundant information storage which improve liminal or subnormal learning.

Animals

Transfer of a learning set between drug states in monkeys.

Four adult male rhesus monkeys, while in either a pentobarbital-induced drug state or a saline control state, were trained on a series of 12 oddity problems. Tests in the opposite drug or saline state were administered after acquisition of each problem in order to determine the amount of transfer between the disparate states. All tests included presentation of problems not previously seen (novel problems). Tests 2-11 also included presentation of problems trained beyond criterion level (overtrained problems). During early tests only the overtrained problems exhibited transfer to the opposite drug or saline state. However, during the later tests, as the monkeys acquired the learning set in the training state, both the novel and overtrained problems were correctly solved in the test state. This indicates that the concept of oddity, rather than solution of specific problems, transferred between drug states. Interestingly, the overtrained problems exhibited greater transfer on the later tests than on early tests. This may suggest that the transfer due to overtraining is not the same as the transfer due to acquisition of the oddity learning set.

Animals

Reducing stimulus overselectivity in autistic children.

It has been repeatedly reported that when presented with a discrimination task involving multiple cues, autistic children, as compared to normal children, tend to respond on the basis of only a restricted portion of the component cues. This phenomenon has been called "stimulus overselectivity" and has been implicated as a possible basis for some of the pronounced behavioral deficits charactertistic of autism. Examination of the results of several previous studies suggests that the overselectivity effect might be reduced with repeated exposure to testing. However, since the previous studies were not designed to test this hypothesis, no conclusions were drawn regarding variables influencing the reduction of the overselectivity phenomenon. The present investigation was therefore conducted to determine if stimulus overselectivity in autistic children is changed as a function of repeated exposure to testing. Nineteen autistic children were trained on a discrimination task with a cue complex composed of two visual cues. After the children reached criterion on the task, they were exposed to a testing phase with probe trials where the cue components were presented singly. The results indicated that 16 of the children initially showed overselectivity and 3 responded to both cues. Of the 16 children who showed overselectivity, 13 decreased their level of overselectivity with continued testing. These results are discussed in relation to variables in the testing procedure itself and to the literature on selective attention.

Attention

Overselectivity, developmental level, and overtraining in autistic and normal children.

Thirteen autistic children were compared to 13 normal children matched to them in mental age, on performance of a visual discrimination task. Form, color, and size were relevant and redundant cues. The groups did not differ significantly in mean trials to reach criterion or in breadth of learning, and both groups increased their breadth of learning after 50 trials of overtraining. Form was preferred to color and size by both autistic and normal children. Within each group, rank on mental age was highly correlated with rank in breadth of learning. Verbal and nonverbal autistic children did not differ in breadth of learning or in dimensional preference. Even nonverbal autistics equaled the performance of their normal controls. Our results suggest that overselective attention is better understood as part of a general developmental lag in cognition in autistic children than as a specific deficit underlying psychotic behavior.

Attention

The effects of schedule of reinforcement on stimulus overselectivity in autistic children.

Recent research demonstrated that when autistic children are presented a discrimination task with multiple cues, they typically respond to an abnormally limited number, usually one, of the available cues. This phenomenon, termed "stimulus overselectivity," has been implicated as a possible basis for many of the behavioral deficits characteristic of autism. The present investigation was conducted to systemically analyze the effects of changing the schedules of reinforcement during discrimination training on subsequent stimulus overselectivity. Twelve autistic children were taught a discrimination involving multiple visual cues, with a CRF schedule of reinforcement. The children were then overtrained on either the same (CRF) schedule or on a partial (VR:3) reinforcement schedule. Subsequent overselectivity on single-cue test trials was then assessed. Results suggested that significantly less overselectivity occurred when the children were presented with the VR:3 reinforcement schedule during overtraining. These results are discussed in terms of variables influencing overselectivity and in terms of implications for designing treatment procedures for autistic children.

Adolescent

Parental ratings of treatments of self-injurious behavior.

This study examined (a) how parents of autistic children, parents of other handicapped children, and parents of nonhandicapped children rate, as a whole, acceptability of time-out, differential reinforcement, overcorrection, and shock as treatments for self-injurious behavior, and (b) whether these parents show differences, as groups, in ratings of these treatments. On the Treatment Evaluation Inventory, all groups consistently rated differential reinforcement, time-out, and overcorrection as acceptable and shock as unacceptable. Differential reinforcement was consistently rated as the most acceptable, but the groups differed in ratings of acceptability of other treatments. On the Semantic Differential, ratings of differential reinforcement, overcorrection, and time-out did not differ. However, shock was consistently rated as the most potent and active of treatments as well as the most unacceptable. The implications of these findings for treatment of autistic and other handicapped children are discussed.

Adolescent

Treatment of assaultive hair pulling in a multihandicapped youth.

The course of treatment for hair pulling in a moderately retarded, visually impaired 9-year-old male is described along with the effectiveness of an ammonia inhalation procedure to eliminate this behavior. However, before discovering this successful procedure, other well-known techniques such as DRO, TO, overcorrection, and shaping all failed. Since rapid treatment effectiveness could be assumed to be the norm, given the operant literature, the extensive course of treatment reported here serves to document that perseverance may also be a necessary component of successful behavior management strategies.

Aggression

Suppression of pica by overcorrection and physical restraint: a comparative analysis.

Overcorrection and physical restraint procedures have been shown to be effective in controlling certain classes of maladaptive behavior in mentally retarded persons. In the present study, an alternating treatments design was used to measure the differential effects of overcorrection and physical restraint procedures in the treatment of pica. Changes in collateral behaviors were also monitored. Each occurrence of pica was followed by either an overcorrection procedure or a physical restraint procedure. Although both procedures reduced the occurrence of pica and had a similar effect on the occurrence of collateral behaviors, physical restraint was clinically more effective in terms of immediate response reduction.

Adult