Computer-based systems for applying psychological knowledge

Computer-based systems have long been seen as a means for applying psychological knowledge to instructing. However, from many years of research and development on instructional design and on using computers for instructing, we learned that the current instructional techniques are based on an inadequate scientific knowledge base and are poorly implemented. In order to do better, improved techniques based on modern cognitive science must be developed, and computer-based aids are needed to assist their application. Furthermore, a standardization and distribution system is needed to identify effective instructional programs and make them available. This seems especially important if we hope to have broad impact on education and training.     

Visual control of discrete aiming movements

An experiment is reported which investigated the visual control of discrete rapid arm movements. Subjects were required to move as rapidly as possible to several target width-movement distance combinations under both visual and non-visual conditions. The movement time (MT) data were supportive of Fitts' Law in that MT was linearly related and highly correlated to the Index of Difficulty (ID). MT was also similar for different target width-distance combinations sharing the same ID value. The error rate analysis, which compared visual to non-visual perfromance, indicated that vision was only used, and to varying degrees, when MT exceeded 200 ms (3.58 ID level). There was some evidence that vision was differentially used within target width-distance combinations sharing the same ID. Estimates of endpoint variability generally reflected the results of the error rate analysis. These results do not support the discrete correction model of Fitts' Law proposed by Keele (1968).     

Sensory and motor impairment in the nerve compression block

Recently nerve compression block as a method of investigating movement control without kinaesthetic feedback has been questioned on the grounds that motor impairment (as measured by nerve conduction parameters) is a confounding factor. In order to clarify the relationship between sensory and motor function, behavioural data was obtained on both at systematic time intervals throughout the duration of the block. The findings indicated that significant decrements in tapping measures occurred somewhat earlier in the time course of the block than decreases in kinaesthetic discrimination. Also, contrary to assumption, the majority of subjects ceased to perform prior to total kinaesthetic loss. The data suggest that motor impairment is a “crucial” issue (Laszlo, 1966) in the use of this technique, and provide further behavioural support for the neurological findings of Kelso, Stelmach and Wanamaker (1974).     

THE MODIFICATION AND GENERALIZATION OF VOICE LOUDNESS IN A FIFTEEN-YEAR-OLD RETARDED GIRL1

A fifteen-year-old severely disturbed girl was treated for aphonia. Because of the extent of her withdrawal, the subject was conditioned in a laboratory setting and received tokens for speaking loudly enough to operate a voice-operated relay. Conditioning at first consisted of saying 100 monosyllabic words, with the possibility of reinforcement on each word. Later, the subject was required to say a polysyllabic word, and finally, five or six words per token. The subject was shaped to speak with normal loudness in the laboratory, and generalization to a reading situation in the laboratory was measured and observed to occur, at first for a few minutes, and later for a longer period. Generalization to a reading situation in the classroom did not occur, but the subject's voice loudness also increased in the classroom when several new reinforcement contingencies were put into effect there.     

Components of displacement adaptation in acquisition and decay as a function of hand and hall exposure

Tests of proprioceptive shift (PS), visual shift (VS), and negative aftereffect (NA) were made during 25-min exposure to 20-D displacement and during a subsequent 30-min dark decay period in two separate experiments. Different groups of subjects explored hallways or viewed their active hand during exposure. VS was greatest in hall exposure, while PS was greatest in hand exposure. Larger VS occurred in the second experiment, where test procedures were modified to minimize a tendency to center the target within the momentary or remembered field of view. Substantial and possibly complete VS decay occurred when the initial level of adaptation was high, but although PS decay was substantial, it was not complete. In all conditions, the sum of VS and PS numerically exceeded the NA, and this difference tended to be largest and significant in the hall exposure. Implications of this effect for the two-component additivity hypothesis are discussed.     

Hypnotic susceptibility and familial handedness

The possible relationship between hypnotic susceptibility and familiar handedness was examined. In a mass-testing session of students enrolled in introductory psychology classes, subjects were administered the Harvard Group Scale of Hypnotic Susceptibility, Form A and were also required to complete a questionnaire that ascertained information on their dominant handedness and that of their immediate family relatives. Subjects who had immediate sinistral relatives scored significantly lower in hypnotic susceptibility compared to those who had a history of familial dextrality. When immediate relatives of the original subject pool were tested on hypnotic susceptibility level, sinistral relatives scored lower in susceptibility than dextral relatives. This may indicate the existence of a familial component in hypnotic susceptibility.     

Loudness and reaction time: II Identification of detection components at different intensities and frequencies

Equal-loudness contours were first obtained for five stimulus frequencies at four stimulus intensities. These 20 stimuli were then presented as reaction-time signals in a Donders C paradigm. The Z-transform method of convolution, as applied in linear systems identification, was used to deconvolve an empirically generated response (or “residual”) distribution (T_R) from each of the 20 reaction-time (RT) distributions obtained at different intensities and frequencies. The resulting sensory-detection (t_d) models formed exponential densities at strong intensities (60 and 80 phons), but their shapes were either gamma or normal at relatively weak intensities (20 and 40 phons). Our analyses support the idea that the simple reactiontime process (RT) is a convolution (or sum) of two component stages: stimulus detection (t_d), followed by response evocation (t_r). Based on the shapes of t_d, a neural-impulse theory is offered to account for the detection of simple auditory RT signals.     

Factorial analysis of the MMPI profiles of low back pain patients

To examine the interrelationships of MMPI scale scores among low back pain patients, 50 profiles were scored on the traditional 13 scales, Hanvik's Lb scale and seven subscales derived from Scales 1 and 3. The profiles were randomly divided into two equal samples and factor analyzed. Comparison of the two samples yielded three common factors. The first factor measured severity of the symptoms, the second assessed the level of anger and aggression and the third assessed the psychogenic components of the syndrome. The implications of the factors are discussed.     

Premarital counseling: Approaches,objectives, content,and evaluation—a bibliography

A major problem for the premarital counselor is that the literature in the field is scattered throughout numerous journals and books representing several disciplines. Since counselors tend to subscribe to and read the literature from their own academic discipline, they may be unaware of what is being written elsewhere. This article contains a bibliography of what the authors consider to be the most relevant books and articles on premarital counseling published by the various disciplines. For the convenience of the reader, each listing is also coded as to its content.The authors express their appreciation to Charles R. Figley, Ph.D., Douglas H. Sprenkle, Ph.D., and Diane Spencer, M.S., for their assistance in the preparation of this paper. The valuable assistance of those contributors who notified the authors of their publications is gratefully acknowledged.