Alpha brain wave production as an interpolated task in a Brown-Peterson paradigm.

Rehearsal, backward counting, and production of alpha brain-waves were used as interpolated tasks in a Brown-Peterson paradigm to determine their effect upon verbal retention. A within-subjects design was used in which trained subjects were told on a given trial either to produce alpha rhythm, mentally rehearse, or count backward following presentation of a CCC trigram. Results for the backward-counting condition duplicate, for the retention intervals used, the shape of the classic Peterson and Peterson forgetting curve but indicate little loss of memory in either the rehearsal or alpha conditions. No siginificant difference was found between the alpha production and rehearsal conditions.     

Detection of a deficit in visual discrimination of pattern following lesions of anterior cortex: role of type of motivation.

6 albino rats were trained under appetitive motivation to perform diametrically opposed visual discriminations of pattern via opposite eyes. Small lesions were subsequently placed unilaterally in anterior neocortex. Following a period of post-surgical recovery, subjects were re-trained on the diammetrically opposed discriminations in alternating 10-trial blocks. Every subject made more post-surgical errors on the discrimination mediated by the eye contralateral to the lesion. Since albino rats have virtually complete decussation of the visual system, this indicates selective impairment in mediation of performance of pattern discrimination in the part of the lesioned hemispheres. Thus, findings previously obtained in studies involving aversive motivation are general to appetitively motivated tasks.     

Use of perceptually based apparatus to train adult women's performance on a Piagetian measure of the horizontality concept.

A segmented container called the V-box was designed to train adult subjects who fail a Piagetian type measure of the horizontality concept. The first segment appears round when viewed from straight an and virtually all adults were able to predict correctly howthe water line would appear when this segment was half filled with water. Partitions can be removed and the water allowed to fill up the entire container which has straight-line boundaries. On a pretest, 28 of 43 subjects failedto indicate the water line correctly on the container, when its straight-line characteristics were apparent. Of these 28, 18 were able to do so after being exposed gradually to the container's rounded segment and, step by step, to its elongated segments with straight-line boundaries. The difference in pre- to posttest change in performance between these 18 subjects and the 10 control subjects was significant.     

Multiple encoding of word attributes in memory

Two experiments employing the release from PI method were conducted to determine whether degree of release could be predicted by the amount of denotative attribute overlap between the control and experimental groups. This theory was very appropriate for predicting the results of the first experiment, but was less successful in the second unless a connotative attribute is also introduced. It is suggested that this class of attribute should be included in semantic memory conceptualization.     

Recognition memory for words and pictures at short and long retention intervals

In two experiments, subjects studied a long series of words and pictures for recognition. Retention intervals varied from several minutes to a few months. The complicated testing procedures in Experiment I required the use of a traditional correction for guessing to obtain estimates of subjects' memory performance. A comparable, but simpler, design in Experiment II permitted the calculation of sensitivity and bias measures. In both studies, pictorial memory was superior to verbal memory at all retention intervals tested, and this advantage was essentially constant over time. In addition, the experiments identified an increasing tendency to call verbal test items "old" over time. Bias scores in Experiment H revealed that subjects adopted a more lenient criterion in responding to words than to pictures, and increased leniency was noted for both item types over time. Explanations of the results are offered in terms of differences in initial encoding and of a loss of discrimination between experimental and extraexperimental materials.     

Manipulation of response-contingent unconditioned-stimulus intensity in human eyelid conditioning: A two-phase model analysis

Four groups of human subjects were given 360 classical eyeblink conditioning trials. All groups received the same UCS (unconditioned stimulus) intensity on[Formula: see text] (nonconditioned response) trials but differed in the intensity presented on CR trials. Response probability increased as a positive function of UCS intensity on CR trials. Phase 1 of the two-phase model was longer when no UCS was presented on CR trials, but did not differ in duration among the remaining three groups. Most subjects could be described with a single operator in Phase 2, the operator limit increasing as a positive function of CR-contingent UCS intensity. For subjects requiring different operator limits on CR and[Formula: see text] trials, the latter was lower with high CR-trial intensities but higher with low CR-trialintensities. The results were interpreted to be more consistent with drive theory than with "law-of-effect" or two-factor theories.     

Control-system theory and performance objectives

Behaviorism, the source of the concept of performance objectives, models behavior as an output emitted by an organism. Control theory suggests a different model, in which the stable patterns called behavior are perceptual variables stabilized against disturbances by variations in motor activities. Control theory provides a clear distinction between a learning model and a performance model. Learning is centered around the control of internal variables by means of changes in the organization of performance. Performance is centered around control of perceptual variables, which the experimenter or teacher must learn to share with the subject or student in order to understand what is being performed.     

Group caution at the race track

McCauley, Stitt, Woods and Lipton's finding that groups were more conservative than individuals when betting at a race track has been criticized on statistical and methodological grounds. The present study which does not suffer the shortcomings for which McCauley et al. were legitimately criticized does, nonetheless, sustain their general results and conclusions. Groups were significantly more cautious than individuals when wagering $2.00 on a horse race.     

Cardiovascular responses to avoidance conditioning in the dog: Effects of alpha adrenergic blockade

Laboratory dogs were trained to press a response panel to postpone shocks during daily one-hour avoidance conditioning periods. Each dog was also confined in the experimental environment for 5 hours prior to the avoidance periods. Blood pressure and heart rate were monitored continuously during these experiments from chronically indwelling arterial catheters. Extended training resulted in the emergence of a cardiovascular response pattern during the pre-avoidance interval characterized by gradual increases in blood pressure together with decreases in heart rate. Elevations in both blood pressure and heart rate were sustained during the avoidance periods. During sessions in which alpha adrenergic activity was suppressed by phenoxybenzamine, absolute levels of blond pressure were found to be lower than during control (non-drug) sessions, but a progressive rise in blood pressure continued to be observed during pre-avoidance. These results suggest that sustained cardiovascular responses during avoidance periods are associated with activation of the sympathetic nervous system, but that the gradual rise in blood pressure during pre-avoidance is due to other factors.