Effect of stimulus frequency on subjective vibrotactile magnitude functions

Subjective magnitude functions were determined by the method of magnitude estimation at 60 and 250 Hz at the fingertip and thenar eminence, both with and without a rigid surface surrounding the contactor. When the surround was in place, the slopes of the curves were independent of stimulus frequency. The slopes became frequency dependent when the surround was removed—the lower frequency produced a steeper slope at both body sites. An explanation of the effect is suggested. It involves the frequency characteristics and spatial sensitivity of the receptors.

     

Effects of alcohol and marijuana on dynamic visual acuity: I. Threshold measurements

Alcohol and marijuana produce significant dose-related reductions in dynamic visual acuity. Ten subjects participated in a double-blind experiment involving three dose levels of each drug (including placebo). The reduction of DVA produced by alcohol (1.0 ml 95% ethanol/kg body weight) was greater than for marijuana (15 mg Δ-9-tetrahydrocannabinol), and we suggest that this difference was produced by differential oculomotor effects of the two drugs. We have speculated that reduction in DVA under alcohol may be a contributing factor in alcohol-related traffic accidents.     

Obedience as a function of experimenter competence

The purpose of this study was to investigate obedience to an E’s commands as a function of E competency. Based upon Orne’s (1962, 1969) discussion of the demand characteristics inherent in the typical aggression study, it was hypothesized that E incompetence would decrease S obedience. Competence was manipulated by: (1) presenting some Ss with a nervous and inexperienced E, and (2)“accidentally” killing the victim (a rat) midway through the experiment. Thirty-two undergraduate female Ss participated in the experiment—supposedly a study on the physiological effects of stress. Obedi6nce was operationalized as the difference, in simple reaction time, between trials on which Ss were told that their response might result in shock to the rat and trials on which they were told that their response might save the rat from shock. Significant differences in obedience were obtained between competent and incompetent E conditions, and a significant “kill” effect was found in the competent E conditidn. The results of this study suggested that the extreme acts of obedience observed in the laboratory (e.g., Milgram, 1963) occur only when E is perceived as competent. This finding imposes limits on the generalizability of laboratory studies of obedience.     

A follow-up investigation of families referred to outside agencies

A follow-up study was conducted to determine the outcome of 254 referrals made by 47 school psychologists in New York and New Jersey. The referrals represented randomly selected cases in which the recommendation was made to the families of elementary school childred to use service external to the school setting. Evaluation of referral outcome was determined in light of the reason prompting the referral recommendation. Explanations for the outcome of referrals summarized in this investigation were advanced and the limitations of this study noted.     

Ear differences in the recall of monaurally presented sentences

Using a short-term memory paradigm, with an interpolated task, college students were required to recall monaurally presented sentences. Four types of sentences, representing a factorial combination of Surface Structure, either right-branching or self-embedded, and Semantic Constraint, either semantically normal or semantically anomalous, were used. Analysis of recall data indicated a right ear advantage (REA). This result clearly contradicts Kimura's (1967) “perceptual rivalry” hypothesis which assumes that auditory conflict as induced, for example, through dichotic stimulation, is necessary for producing a REA in verbal processing. It was concluded that short-term and attentional factors contributed to the presence of the REA. No interactions involving Ear and either Surface Structure and/or Semantic Constraint were obtained and, therefore, no conclusion could be drawn regarding the view (Kimura and Folb, 1968; Studdert-Kennedy and Shankweiler, 1970) that the lateralized speech encoding mechanisms operate solely at a phonemic or subphonemic level.     

A scale to measure attitudes toward working

The purpose of this study was to develop a scale that could measure attitude toward work and be used to determine the relation between length of unemployment time and work attitudes. Standardization of the Employment Readiness Scale was completed through its administration to three independent groups (N = 430): (1) employed workers: employees who worked in unskilled, semiskilled, and occasionally skilled job classifications; (2) unemployed individuals who were actively looking for regular employment at the Tennessee State Employment Service; and (3) the chronically unemployed: individuals, who, for the most part, were not looking for regular employment and who were seeking night lodging and meals at the Salvation Army or the Knoxville Union Rescue Mission. Through item analysis, it was determined that 43 of the 45-scale items were significant at or beyond the .01 level. It was further established that a relationship existed between work attitudes and length of unemployment. The longer an individual was unemployed, the less positive was his attitude toward work.     

Effect of simultaneous auditory stimulation on vibrotactile thresholds

Vibrotactile thresholds were determined at 250 and 400 Hz in the presence of (1) the sounds emitted by the vibrator, (2) continuous tonal or narrow-band masking noise, or (3) a pulsed tone synchronized with the vibrator signal. The measure of a cross-modality effect was the threshold shift occurring between each condition and the control condition, in which earmuff silencers eliminated the vibrator sounds. Continuous tones or noise had no effect upon vibrotactile thresholds. However, auditory signals synchronized with the vibrator signals did significantly elevate vibrotactile thresholds.     

Blocking the incorrect alley in a two-drive learning situation

This experiment was designed to test the effect of blocking the path to an irrelevant reward on the subject's later performance when motivated for that reward, with a view to clarifying a well-known problem-situation.

An experimental group of 17 hooded rats was run in a two-choice maze, with food in one goal-box and water in the other, being motivated alternately for one or the other. The wrong goal-box was always blocked. Their performance on the first trial of the daily series was significantly poorer than that of a control group of 18 hooded rats, for which both boxes were always open. This difference persisted when, in a second period of training, the rhythm of motivation was altered for both groups.

It is concluded that blocking an irrelevant reward can have a disturbing effect and that this may be relevant to the problem-situation. It is also shown that such a result is to be predicted from Deutsch's (1953, 1956) theory.