Reflex responses of human lip muscles to mechanical stimulation during speech

The role played by reflex pathways in the production of movement has been a significant issue for motor control theorists interested in a wide variety of motor behaviors. From studies of locomotion and chewing, it appears that gains in reflex pathways can be altered so that activity in these pathways does not produce destabilizing responses during movement. In speech production, recent experimental evidence has been interpreted to suggest that autogenetic lip reflexes (perioral reflexes) are suppressed during sustained phonation or speech production. The present study was conducted to assess the effects of phonation, direction of movement, and ongoing speech production on reflex responses of lip muscles. The present results suggest, in contrast to earlier work, that this reflex pathway is not suppressed or absent because the amplitude of the observed response depends upon the activation levels of the various muscles of the lower lip and, therefore, indirectly on the nature of the gesture the subject is instructed to produce.     

Reaction time methods in the study of motor programming: the precuing of hand, digit, and duration

Recent reaction time analysis of motor programming has utilized a precue stimulus that provides advance information about some or all of the attributes for the upcoming motor response. This kind of precue typically confounds the number of remaining stimuli with the motoric processes under investigation (Zelaznik, 1978). In Experiments 1 and 2 the precuing of hand, digit, and duration of a key press response was manipulated. A new precuing procedure was utilized that does not confound the number of stimuli with the motoric processes under investigation. The findings of Experiments 1 and 2 demonstrate that none of the advance information was helpful in reducing reaction time and as such, suggest that these features of movement are not selected in any particular order. Experiment 3 compared this new method of precuing to the other, traditional method. The results of this experiment suggested that there is parallel processing of the perceptual and motor mental operations in this reaction-time task, since there was an underadditive interaction between the number of stimulus response alternatives and the non-precued movement dimensions. This paper highlights problems inherent in the utilization of precursing methods to understand motor programming processes. It appears that a better understanding about the variables involved in movement control is necessary before examining the order of selection of those variables.     

Perception of social distributions

Accurate representation of the distribution of social attitudes and behaviors can guide effective social behavior and is often essential for correct inferences. We examined the accuracy of people's beliefs about the distributions of a large number of attitudinal and behavioral dimensions. In two studies we measured actual attitudes and behaviors in a student population, and we assessed beliefs by asking subjects to estimate the distribution of 100 students on these dimensions. We examined the accuracy of subjects' perceptions of the means, standard deviations, and distribution shapes. Subjects showed a number of systematic biases, including overestimation of dispersion and overestimation of the means of behavioral distributions and a false consensus bias, but their overall accuracy was impressive.     

Evidence for extending the circumplex model of personality trait language to self-reported moods

We show that self-ratings by 141 undergraduates on 17 items form a circumplex that closely agrees with Conte and Plutchik's (1981) circumplex of personality traits. The order of items on a circumplex, generated by self-ratings following a here-and-now instruction set, scarcely differs from that of a circumplex representing the same ratings averaged over a 2-week period. The configuration becomes more elliptical as one moves from the state-like measures (here-and-now ratings) to pure trait measures (averages), but measurement bias is shown to be the most probable cause of the distortion. Allowing for the limitations of small samples of items and raters, the findings show that the circumplex model represents a valid theoretical construct and does not arise from measurement error or from an illusory implicit personality theory.     

Gender differences in emotional development: A review of theories and research

Theories, data, methodological and conceptual problems concerning the study of gender differences in the development of defenses, emotional expression, recognition, and experiences are reviewed Data indicate gender differences in several areas of emotional functioning, including nonverbal sensitivity, expressiveness, self-reports of anger, fear, and sadness, the quality of defenses, and cognitive correlates of recognition abilities Studies suggest that with development, boys increasingly inhibit the expression and attribution of most emotions, whereas girls increasingly inhibit the expression and recognition of socially unacceptable emotions, e g, anger These differences may be a function of different socialization processes for males and females, which may be adaptations to innate gender differences in temperament, or adaptations to existing sociocultural pressures The present paper argues that emotions motivate and regulate adaptive behaviors, and that researchers must explore gender differences in emotional development as a function of different familial, sociocultural, and interpersonal roles to which males and females must adapt     

The performance of attention-deficit-disordered and normal children on conservation tasks

The present study was designed to investigate whether a specific subgroup of learning-disabled children (attention-deficit-disordered, ADD) differed from their normal counterparts on Piagetian tasks of conservation. The subjects were 34 third-and fourth-grade children. Seventeen children had been diagnosed as ADD; the remaining half were designated as normal. The two groups were equivalent in chronological age, mental age, and intelligence. The results indicated significant differences between the two groups on tasks tapping conservation of substance and number. These results may support the theory of a lag in the development of conservation in children with specific learning disabilities (ADD). Implications of the present research for therapeutic and remedial programs that serve ADD children are also discussed.     

Dispersion in models of categorical perception

A signal detection theory model of auditory discrimination with a nonlinear mapping from stimulus continuum to perceptual continuum can account for the enhanced discrimination at the category boundary found in categorical perception. Properties of this transformation are specified by a unimodal “dispersion function”. Furthermore, it is shown that a system consisting of two acoustic feature detectors with an associated decision function is also a dispersive system, which models categorical perception of a stimulus continuum as well as boundary shifts under adaptation. The effect of detector adaptation on discrimination is discussed in view of three different types of decision variable and different types of detector noise.     

Psychological functioning after severe closed head injury

The residual effects of severe closed head injury on psychological functioning, as determined by data from the Rorschach test, were examined. Thirty-five young adult patients with severe closed head injury were compared to a nonpatient, non-head injured matched group sample of 36 subjects. The utility of the Rorschach test in distinguishing the characteristic psychological functioning of inpatients who have suffered from severe closed head injury was outlined. The apperceptive disturbance, affective/cognitive problems, and interpersonal difficulties were discussed.