Performance of dyslexic children on speech perception tests

Several researchers who have compared the performance of dyslexic and normal-reading children on a variety of different tasks have suggested that dyslexic children may have subtle deficits in the phonemic analysis of spoken as well as written language. Thus it is of interest to know how children who have extraordinary difficulty learning to read can perform explicity auditory-phonetic tasks. Seventeen dyslexic children (10 years of age) and a group of 17 controls were administered tests of identification and discrimination of synthesized voiced stop consonants differing in place of articulation. These were tests of the type used to study categorical perception in adults, adapted for use with young children. Significant differences between dyslexics and controls were found in both kinds of tasks; the pattern of identification and discrimination differences suggests an inconsistency in the dyslexics' phonetic classification of auditory cues. A significant relationship was found between reading level and speech discrimination.     

The effect of modification of expressive displays on vicarious emotional arousal

Several recent experiments have demonstrated that modulation of the facial expressive response is accompanied by changes in autonomic arousal and subjective response to painful stimuli. The present study asked whether facial self-regulation may also bring about changes in covert vicarious emotional experience. Three groups of subjects were exposed to a videotaped model displaying intermittent pain to shock in a differential vicarious autonomic conditioning paradigm. Subjects in the inhibit and amplify groups were asked, respectively, (a) to inhibit their facial muscles or (b) to pose a facial response of pain when the model was shocked. It was predicted that the inhibit group would show less autonomic arousal to the model's expressive display (empathy) and less conditioning (as measured by skin conductance and heart rate change), and the amplify group more empathy and conditioning, than a third group who was given no facial instruction. In fact, the amplify group showed more skin conductance arousal, heart rate acceleration, and activity in response to the model's expressive display of pain than did the other two groups (which were not different from each other), but no more autonomic or facial conditioning. The overall pattern of physiological data is interpreted as generally supportive of a facial feedback theory of emotion: where significant between-groups' differences were obtained in facial activity, as in vicarious instigation, autonomic arousal differences also emerged; where no expressive differences were obtained, as in vicarious conditioning, no differences in autonomic arousal were found.     

On the form and location of the Psychometric Bisection Function for time

The Psychometric Bisection Function for time relates the discriminability of intermediate duration stimuli to a short and long training duration. Bisection Functions for animals (R. M. Church & M. Z. Deluty, Journal of Experimental Psychology: Animal Behavior Processes, 1977, 3, 216–228) confirm Weber's Law and also show indifference between short and long reports at the geometric mean of the training durations. Two discrimination processes are studied which, in combination with different constructions of the subjective time scale, result in Bisection Functions which differ in form and location. The two discrimination processes use a likelihood ratio rule or a similarity rule to compare intermediate durations to the training durations. These rules in combination with two different constructions of the subjective time scale result in four models which conform to Weber's Law. For one of the scales subjective time is a power function of real time with the scalar property on variance (Scalar Timing). For the other, subjective time is a logarithmic function of real time with constant variance (Log Timing). Both Log and Scalar Timing assume normality on the subjective scale. Only three of these models also entail the geometric mean at the indifference point. The exception is Scalar Timing with the likelihood ratio discrimination rule. This model entails indifference at approximately the harmonic mean of the training stimuli. Variants of the remaining three models differ theoretically but alternatives are difficult to discriminate empirically. A contrast is provided by a Poisson Timing subjective scale in which variance increases directly with the mean. This scale results in indifference at the geometric mean for both discrimination rules but violates Weber's Law in both cases.     

On the statistics of vision: The Julesz conjecture

This paper describes a class of random patterns which have the same first-, second-, and third-order statistics as coin tossing, but are visually different. The patterns are counterexamples to a conjecture of Julesz that all the eye can discriminate is first- and second-order statistics.     

Proportionality,linearity, and parameter constancy: Messick and Sentis reconsidered

Messick and Sentis found greater support for weak proportionality in subjects' outcome allocations (suggesting that subjects wish to maintain a constant ratio between outcomes across situations when inputs are held constant) than for constant differences between outcomes. They claimed that their data thus provided stronger support for Adams' ratio definition of equity than for Harris' linear formula. A dialogue between the two sets of authors establishes that (1) so far as their specification of fair outcomes is concerned, Adams' formula is a special case of the linear formula; (2) weak proportionality does not necessarily follow from Adams' formula and can be derived from the linear formula; (3) Adams' formula applied to subjective (rather than experimenter-defined) inputs nevertheless provides a more natural base from which to derive weak proportionality than does the linear formula in its general form; (4) excellent fits to several sets of data, including much better fit to Messick and Sentis' data than that provided by weak proportionality, are obtained if we assume that subjects use allocations which are a weighted average of those implied by Adams' formula, the Equality principle, and Komorita and Kravitz' Equal Excess Norm; and (5) a fit to Messick and Sentis' data that is almost as good as that provided by the weighted solutions model is obtained by assuming that subjects apply Adams' formula to subjective inputs and subjective outcomes that are different from the corresponding experimenter-defined values. It is agreed that the delineation of the relationships among observable properties of outcome distributions, alternative equity formulae, and different psychological processes is as important as it can be devious.     

The air gap phenomenon in children's landscape drawings

The “air gap” phenomenon was found to be very common in the free landscape drawings of middle and later childhood. Three experiments are reported in which the contextual cues for such drawings were systematically manipulated. When subjects were supplied with drawing sheets constructed to imply the absence of the air gap, the phenomenon was eliminated in most of their drawings. When supplied with sheets constructed to imply its presence, most subjects produced air gap drawings using contextually provided reference lines. There were no consistent transfer effects across different cuing orders. The susceptibility of the air gap phenomenon to modification by task manipulation suggests that it results from problems of production rather than from defects in the child's internal representation of the world.     

The computer psychiatrist: How far have we come? Where are we heading? How far dare we go?

The use of computers in psychiatry and psychology is reviewed. It is noted that computers are already being used successfully for consultation, interviewing, and continuing education. Issues related to the usage of computers in mental health are discussed. Guidelines for future work in the area are suggested.     

Design and implementation of a microcomputer-based adaptive testing system

Adaptive testing is a relatively new form of test administration in which a test is tailored to the individual taking it by choosing items most informative about that person. Methods for determining which items are most appropriate take on a variety of forms, some requiring extensive computation, and almost all requiring administration by a computer. The increasing availability of inexpensive microcomputer systems has made adaptive testing possible when access to larger computer systems is impractical. To make implementation of a variety of adaptive testing methods feasible on a microcomputer, a system efficient from both the examinee’s and the test constructor’s perspectives is necessary. This paper begins by briefly outlining the strategies of adaptive testing developed to date and showing how, structurally, they can be grouped into three general categories. Considerations in design of a test-specification subsystem are then discussed as they relate to this categorization. Finally, a specific implementation of a subsystem for use under the CP/M microcomputer operating system is described. Techniques used to make the extensive computations required by adaptive testing feasible on a microcomputer are presented.     

Developing a laboratory course using PASCAL on the Apple II

Several resources are available to the person seeking to develop a laboratory course that utilizes microprocessors. Several roles for such equipment are envisioned, and some of the issues regarding types of equipment and programming languages are addressed.