Experimental Ss Research Articles

Behavioral effects of stimulation by UHF radio fields.

20 male albino rats were used as Ss in determining behavioral effects of ultra high frequency radiation. Experimental Ss were exposed to low intensity (50,000 mV), low frequency (300 mc to 920 mc) UHF radio waves for 47 consecutive days. Radiated rats were more active than non-radiated rats during the early part of the experiment, but became less active as the days of radiation increased. The UHF group was more emotional than the non-UHF group and showed a gradual increase in the latency of recovery from electroshock convulsion. No differences were found for weight, audiogenic seizures, and water consumption. Results suggest that (a) some time is required for UHF to have a consistent effect on behavior, and (b) the effects on behavior may be non-thermal and related to neurophysiological substrates.

Effects of guided learning experiences in developing probability concepts at the fifth grade level.

A program of learning experiences designed to develop an understanding of selected probability concepts was administered to fifth grade Ss. An equated control group viewed two films which did not deal with probability concepts. Four post-tests were used. Results indicated significant differences in favor of the experimental Ss, including a test of “maximizing success” when prior knowledge as to input level was not available and no extraneous rewards were used.

Semantic satiation in concept formation.

This study deals with generalization of the semantic satiation effect to a concept formation task which involves the grouping of words into classes. Experimental Ss were given satiation treatment on words which were thought to mediate solution to the classification task, while control Ss were given satiation treatment on irrelevant words. It was shown that experimental Ss differed from controls with respect to the type of solutions given in the concept formation task.

EFFECT OF STRYCHNINE SULFATE ON LOCOMOTOR ACTIVITY.

The effect of strychnine sulfate upon spontaneous locomotor activity in an open field was determined for 20 naive male Wistar rats. The experimental Ss were injected ip with 1.0 cc/kg of a 01% solution of strychnine sulfate in normal saline and the control Ss received a similar injection of 1.0 cc/kg of normal saline. All Ss were given 2 trials 7 days apart in the open field, with the injections preceding the second trial. The behavioral change from Trial 1 to Trial 2 for the control group was compared with that for the experimental group. Strychnine sulfate significantly reduced spontaneous locomotor activity in rats. A significant correlation was found between scores on the first and second trials of the experimental Ss. It was suggested that the concept of “orienting-exploratory behavior” could account for reduced locomotor activity.

Children's Preferences for Differing Degrees of Novelty

Sixty experimental Ss were individually habituated to an array of eight small toys. Following this, each child was shown four additional arrays and asked to choose one for further play. The five arrays represented a series graduated with respect to degree of novelty as follows: 0, 25, 50, 75, and 100 per cent. Anxiety scores for each child were obtained by means of independent ratings by three teachers on a scale devised for this purpose. It was found that for the total group the preference value of a toy array increased as a direct function of its degree of novelty. Older children, boys, and lowanxious children preferred greater novelty significantly more frequently then did younger children, girls, and high-anxious children.

CHILDREN'S PREFERENCES FOR DIFFERING DEGREES OF NOVELTY

Sixty experimental Ss were individually habituated to an array of eight small toys. Following this, each child was shown four additional arrays and asked to choose one for further play. The five arrays represented a series graduated with respect to degree of novelty as follows: 0, 25, 50, 75, and 100 per cent. Anxiety scores for each child were obtained by means of independent ratings by three teachers on a scale devised for this purpose. It was found that for the total group the preference value of a toy array increased as a direct function of its degree of novelty. Older children, boys, and lowanxious children preferred greater novelty significantly more frequently then did younger children, girls, and high-anxious children.

The Effect of Intermittent Presentation of Goalbox Cues on Resistance to Extinction under Spaced and Massed Conditions

Twenty-four male albino rats on a 23-hr. food-deprivation schedule were run in a straight runway to food reward in the presence of 3 distinctive stimulus cues. Ss were then divided into 2 matched groups, an experimental and a control. The control group was extinguished with all 3 cues present. Experimental Ss were extinguished with only 1 of the cues present randomly on any trial. Experimental Ss were shown to be more resistant to extinction in terms of number of trials to extinction as well as running time. These results were held to be contradictory to the discrimination hypothesis. An explanation of these results in terms of a slower decrement in motivation was offered as well as ofher possible explanations.

RETROGRADE AMNESIC EFFECT OF AUDIOGENIC SEIZURE ON THE REVERSAL OF A MAZE RESPONSE.

Two groups of mice were given acquisition trials followed by reversal training in a water maze. Experimental Ss were convulsed with a single audiogenic seizure immediately following the last reversal trial. 50% of the latter Ss showed retention of the initial response, but retrograde amnesia for the reversed maze habit. Control Ss all showed retention of the reversed response. The data tend to support the conclusion that audiogenic seizure is partially effective in disrupting the consolidation of the memory trace.

保存および推移律の学習による変容

An experimental education was carried out to examine the following hypotheses.1) The acquisition of conservation of length, weight and liquid measure can be facilitated by an instructional procedure consisting of verbal explanation combined with manipulating concrete materials.2) Ss, who acquire consevation of one of these physical attributes by training, have a tendency to generalize this principle to the two other attributes.3) Ss who comprehend conservation of an attribute also grasp its transitivity simultaneously.Ss were 40 4-to-6-year-old children, who at the pre-training test had shown neither the symptom of conservation nor that of transitivity as to any of these 3 attributes. They were divided into 4 homogeneous groups with a C. A., of 5: 5 as a mean. Three groups were served as an experimental Ss (Exp. Gr.) Gr. 1 was trained as to length, Gr. 2 weight, and Gr. 3 liquid measure, respectively. The remaining one was a control group (Con. Gr.).Each child in each Exp, Gr. received two sessions of 10-15 min. individual tranining in two consecutive days. In these sessions the E. explained conservation based on various grounds, e. i., i) identity or the material without addition or subtraction, i i) empirical reversibility of any transformation, i i i) compensability of loss in one dimension by gain in another.Post-training test was administered to these Ss 3 weeks later.The results were as follows1) Hypothesis 1 was veriffied. Ss who were diagnosed as conservers at the post-training test were 9 in Gr. 1, 9 in in Gr. 2, and 8 in Gr. 3 in number. On the contrary, none of the Con. Gr. Ss answered all of conservation items. of any one attribute correctly.2) Hypothesis 2 was supported. Scores of Exp. Gr. Ss as to two attributes without training increased significantly, while those of Con. Gr. Ss showed no marked improvement.3) Hypotheses 3 also seemed tenable, because in the Exp. Grs. the number of correct responses on transitivity tasks increased significantly.

On the “secondary reinforcing” effect of shock for the correct response in visual discrimination learning

The finding that shock for a correct, food-reinforced response in visual discrimination training tends not to retard performance, and may even facilitate it, has been interpreted by some investigators as indicative of an acquired reinforcing property of the shock. To assess this interpretation, 40 hungry rats were given either no-shock or shock-right acquisition training, followed by extinction training in which the experimental Ss then received (a) shock for the previously correct response, as before, (b) no shock, or (c) shock for the previously incorrect response. The performances of these subgroups provided no evidence of an acquired reinforcing property of the shock, indicating instead an avoidance effect specific to the shocked arm.

The effects of amygdaloid stimulation on passive avoidance

Noncontingent, continuous stimulation of the amygdala in the rat, particularly the basolateral area, impairs the acquisition of a passive avoidance response. Experimental Ss (N = 23) approached and received more mouth shocks from an electrified water spout than control Ss(N = 23).

Effects of inspection figure persistence on a figural aftereffect

Four experimental and four control Ss were presented monocularly with a large white circle on a black background (Inspection figure). Then Ss were asked to switch to the opposite eye and make relative size judgments of two smaller circles, equal in size, one of which (the T-figure) was centered on the same point as the I-figure. For FAE control Ss the I-figure was removed during and subsequent to the brief period required to change to the opposite eye, whereas experimental Ss were treated identically except that the I-figure persisted in its former position during testing. Control Ss typically judged the T-figure to be smaller than the comparison figure, thus exhibiting reliable figural aftereffects. Experimental Ss typically judged the T-figure to be larger than the comparison figure, exhibiting a reliable reversal of FAE.

Magnitude of reward in selective learning

The growth of incentive motivation was investigated in a two choice discrimination using three groups of 10 Ss for 300 trials. The experimental group was trained with 20 mg and 97 mg rewards. One control group received 20 mg while the other control received 97 mg on all trials. Asymptotic running speed was not achieved, but the converging speeds of the control groups tended to support the “habit” hypothesis. Both a negative contrast effect, where the experimental Ss ran slower to 20 mg than did the controls, and a positive contrast effect, where the experimental Ss ran faster to 97 mg than did the controls, was observed.

CHANGES IN PERFORMANCE AS RELATED TO VERBAL CONDITIONING OF ATTITUDES TOWARD THE EXAMINER.

In social influence situations such as psychotherapy, hypnosis, and placebo, the individual's attitude toward his role of S or patient is an important variable. The 20 experimental and 19 control Ss were mothers of nursery school children who participated in this “medical research.” After completing two questionnaires, all Ss completed six dynamometer trials. A 54-item Medical Science Questionnaire (MSQ) was then administered. After 24 non-reinforced “operant” items, experimental Ss were reinforced for responses favorable to medical science, while control Ss received no reinforcement for their responses to all 54 items. After this experimental manipulation, all Ss repeated the dynamometer measure. Compared to the control group, the experimental Ss increased significantly in both their favorability of responses to medical science and dynamometer effort. The results indicate that attitudes toward medical science may be significantly influenced by verbal conditioning and that improvement of such attitudes is associated with improved performance on a task identified with and requested by the examiner.

Serial position effect as a function of intertrial interval

Summary A discrimination theory, stating that serial position effects are dependent upon the ITI for providing a discriminable order cue, was tested by the following experimental conditions: (1) where the ITI was eliminated by equating it with the ISI, (2) where the ITI was eliminated and the beginning of the list was disguised, and (3) where the ITI's location was varied. These groups were compared with a control condition (traditional serial presentation). All experimental conditions significantly reduced primacy-recency effects and retarded rate of acquisition. Experimental Ss typically utilized their own discriminable item for establishing an idiosyncratic serial position curve.

Rate of Learning and Associative Inhibition

Previous studies suggest that susceptibility to associative inhibition may vary inversely with learning speed. To investigate differential effects of interference, fast and slow Ss learned a list of paired adjectives to a common performance criterion. Experimental groups recalled under interference conditions produced by the interspersing of new items in the recall list. Interference occurred both when Ss were instructed to learn the new items while recalling those previously learned and also when Ss were instructed to attend only to previously learned items. Mean recall scores for experimental Ss were significantly inferior to those of a control group. Slow learners were more adversely affected by interference than fast learners.

CHANGES IN CHILDREN'S VERBAL BEHAVIOR AS A FUNCTION OF SOCIAL APPROVAL, EXPERIMENTER DIFFERENCES, AND CHILD PERSONALITY.

This study investigated the influence of attributes and sex on the verbal conditioning of elementary school children. Personality attributes were derived from teachers' ratings on Peterson's problem checklist. Forty-eight fourth-grade children were selected from a larger sample on the basis of their scores on the personality and conduct factors. Taffel's sentence-construction technique was used. Experimental Ss were reinforced by the verbalization good when they used a first-person pronoun, while control Ss were given no reinforcement. Effectiveness of social approval as a reinforcer was again demonstrated, but the effects of attributes of the child, the sex of E, the sex of S, and interactive effects of E and S were not demonstrated. As only one S verbalized awareness of the response-reinforcement contingency, the effects of awareness could not be assessed.

Sublimal discrimination and the concept of vigilance

Ten experimental Ss underwent a procedure whereby a subliminal 500 c.p.s. tone (CS) was paired with photic stimulation (UCS). The “arousal” reaction of the alpha rhythm of the EEG was used as evidence of a CR. A subliminal tone of 800 c.p.s. and a 6-per-sec. pulsed subliminal shock were used to test for discrimination. Ten matched control Ss underwent the same procedure as the experimental Ss except that the 500 c.p.s. tone was never paired with the photic stimulation. Since experimental Ss gave the CR to the 500 c.p.s. subliminal tone only and not to the two neutral stimuli and control Ss gave no evidence of a CR, it was concluded that discrimination between subliminal stimuli occurs. The results of the study imply that some selective mechanism operates at a neural level whereby significant stimuli are attended to and non-significant stimuli are not.

Subliminal conditioning of the alpha rhythm

Six experimental Ss were used to condition the reaction-to-shock (UCS) of the alpha rhythm of the EEG to a subliminal auditory stimulus of 500 c.p.s. (CS). A matched control group of six Ss was similarly stimulated, but shock and the CS were never paired. On test trials there was a difference between experimental and control groups in reaction to the subliminal stimulus, yielding evidence of conditioning in the experimental group. A neutral subliminal stimulus of 800 c.p.s. was also used to test ability to discriminate between subliminal stimuli. Large individual differences were found, and results are indeterminate. The findings raise neurophysiological questions in terms of cue and arousal functions.

Toward a theory of “hypnotic” behavior: Positive visual and auditory hallucinations

Two interrelated series of experiments are critically reviewed: experiments concerned with the objective validity of hypnotic visual and auditory hallucinations; and experiments which set out to specify the variables relevant to eliciting such hallucinations. The first series of experiments failed to demonstrate that hypnotic hallucinations produce objective effects which are the same as the effects produced by visual or auditory stimulation or different from the effects produced by imagining. Experiments in the second category indicate that the so-called “trance state” may be an extraneous variable in eliciting testimony from experimental Ss that suggested objects were seen and suggested sounds were heard. The relevant variables appear to include: (1) direct suggestions to see (nonexistent) objects and to hear (nonexistent) sounds, that are (2) given firmly and seriously to Ss who are motivated to perform to the best of their ability on assigned experimental tasks.