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.     

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.     

Conditioned placebo responses

Following earlier animal research, we attempt to condition placebo effects in human subjects. Four groups of 8 voluntary subjects were told that the experimenters would test a powerful new analgesic cream over three sessions by assessing its ability to reduce experimentally induced pain. The analgesic cream was, in fact, a placebo. In the first session all subjects were tested with and without the cream to assess their placebo response. In the second session, to condition two groups (with differing stimulation levels) to experience pain relief in response to the placebo, we repeatedly paired a reduction in nocioceptive stimulation with placebo administration. (Subjects were unaware that stimulation levels were manipulated). To condition the other two groups (with different stimulation levels) to experience an exacerbation of the pain, we paired an increase in nocioceptive stimulation with placebo administration. In the third session, all subjects were again tested for placebo response. Results suggested that placebo responses are conditionable in the laboratory in both a positive and negative direction. The clinical implications of a learning theory of placebo behavior are discussed.     

Passive avoidance in syndromes of disinhibition: psychopathy and extraversion

According to the physiological animal model proposed by Gorenstein and Newman (1980; see also Newman, Gorenstein, & Kelsey, 1983), psychopaths and extraverts may be characterized by a common psychological diathesis related to behavioral inhibition (see also Fowles, 1980; Gray, 1982). One aspect of this diathesis involves deficient passive avoidance learning, which has been central to explanations of "unsocialized" (e.g., Trasler, 1978) and antisocial behavior (e.g., Hare, 1970). Results from three experiments supported our prediction that psychopaths and extraverts would exhibit deficient passive avoidance relative to nonpsychopaths and introverts, respectively. In addition, the passive avoidance deficit was particularly evident in tasks that required subjects to inhibit a rewarded response in order to avoid punishment. The latter finding may be important for explaining the inconsistent results regarding passive avoidance learning in psychopaths (e.g., Chesno & Kilmann, 1975; Schmauk, 1970). Discussion of the results focuses on the importance of reward in mediating the passive avoidance deficit of "disinhibited" individuals and on the existence of an indirect relationship between psychopathy and extraversion: one that is consistent with the observed experimental parallels as well as with the more ambiguous evidence regarding a direct correlation between measures of the two syndromes.     

A factor analytic investigation of children's nighttime fear and coping responses

Checklists of children's nighttime fears and nighttime coping responses, completed by 178 8- to 13-year-old children and one of their parents, were factor analyzed. The resulting factors from each checklist were comparable for children and parents. The nighttime fear categories consisted of content around security either for one's personal life, loss, or safety or for others' safety and continued presence; imaginal-numinous concerns; and characteristics inherent in a nighttime situation. The coping categories consisted of responses related to internal self-control, social support, support from inanimate objects, prayer, and avoidance or escape either by controlling the inanimate environment or by controlling others.     

Personality variables and metabolic control in children with diabetes

Insulin-dependent diabetic children and a group of their nondiabetic peers were compared on measures of self-concept, locus of control and health locus of control. A metabolic measure of long term diabetes control was also obtained on the children with diabetes. Data analyses revealed that metabolic control was not related to any of the personality measures in the diabetic sample. Diabetic and non-diabetic children did not differ on measures of locus of control and self-concept, but diabetics exhibited a health locus of control which was significantly more internal than that of control subjects. A possible explanation for these results was discussed and practical implications for health care providers working with young diabetics were presented.     

The effect of diagonality on reconstruction of patterns by preschool children

The study examined the contribution of various aspects of pattern complexity to children's difficulty on reconstruction of patterns. Specifically, diagonal pattern components and spatial orientation of patterns were considered. Twenty-four children between 16 months and 31 months were presented eight 5-square patterns on a 3 X 3 matrix of squares. The squares lighted, went dark, and then could be relighted by the child if touched. Accuracy of reconstruction was determined by the number of squares correctly chosen by the child during reconstruction. The eight patterns were rated according to Leeuwenberg's code length method, Garner's rotation-and-reflection method, Halford and Macdonald's rating scale, and a simple count of the number of diagonal lines. Analysis of children's responding indicated that number of diagonal lines was more predictive of memory performance than the other three rating systems, implying that diagonality is an important feature of pattern complexity that should be included in ratings of patterns used in research with children.     

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.