Progamming time in serial tapping responses as a function of pathway constraint

Summary This study varied the accuracy demand within a linear series of targets to investigate the effect of movement-pathway constraints on response-programming time. Sidaway, Christina, and Shea (1988) have suggested that constraints placed upon movement initiation by the demand for response precision may play an important role in determining the length of the programming process. By varying the subtended angles of a series of three targets, this experiment tested the specific prediction of Sidaway et al. that programming time may be a function of the target, within a line of targets, that subtends the smallest angle at the start position. It is this target that demands the greatest precision in the movement pathway. Subjects participated in a series of conditions in which the size and placement of the target that imposed the maximal constraint was varied. In each condition the subjects were required to strike a series of three targets with a stylus in a simple reaction-time paradigm. Analysis of the reaction-time results revealed a significant effect of size of constraint, but no effect of position of constraint. Analysis of the movementtime data dispelled movement-duration and movement-velocity interpretations of the results and intimated a possible online trajectory-correction process.Portions of these data were first presented at the Annual Meeting of the Psychonomic Society in Atlanta, Georgia, November 1989.     

Job demands,supports, and constraints as predictors of psychological strain among schoolteachers

The literature on occupational stress contains two relatively independent bodies of literature, one of which shows that stress results from high work demands and the other which indicates that stress is associated with low levels of autonomy/discretion. Recent work has also shown that social support moderates the relationship between environmental stress and psychological strain. This paper uses a model of stress which assumes that stress is a function of the balance of demands, supports, and job constraints. The model is tested on a homogeneous professional group of workers because a previous study had suggested that models of this kind are powerful enough to detect differences in psychological strain when unskilled groups are compared with managers, but not when managers are compared with managers. The empirical results of this study of teachers show very modest support for the model, but confirm that the percentage of variance accounted for by these sorts of measures is rather small.     

The role of category information in word identification: A parallel decision model

Four experiments consider the role of semantic category information in word identification using a serial classification reaction time paradigm. Experimental variables were manipulated by varying the semantic properties of blocks of trials and the target search instructions. Experiments 1, 2, and 3 investigated the facilitation on target word recognition of manipulating the categorical homogeneity of the nontarget words. An homogeneous nontarget set facilitated the classification of unrelated target words. This category contrast effect was obtained in all conditions, although its magnitude depended upon target search instructions. Experiment 3 also investigated whether word identification was inhibited if subjects were prevented from utilizing the category information to distinguish target from nontarget words. Target and nontarget word identification was slower under such conditions. Experiment 4 demonstratd that both the category contrast and category interference effects were dependent upon the use of short response-stimulus intervals to define a functional semantic background. This suggests the category effects are perceptual in nature. Current models of word recognition cannot easily explain the findings. A committee decision model is outlined to accommodate the data; the model proposes that visual analysis, identification, and categorization proceed in parallel.     

Intrameal eating patterns of obese and nonobese humans.

Two experiments were conducted to test whether the intrameal eating patterns of obese and normal-weight human subjects are different. The first experiment was conducted in a laboratory under the pretense of a taste test. Eating was observed and data were compiled for seven parameters related to eating. The second experiment was conducted under field-study conditions with the subjects unaware of their participation. Few statistically significant differences in eating behavior were observed between obese and normal-weight subjects. These results are in contrast to the majority of previous work.     

The chicken and the egg: a hindsight view of therapy

In this paper the authors suggest that instead of holding the view that the sequence of therapy follows the path of first interviewing and gathering data, then understanding and finally intervening on the basis of what is thought to be the cause of the problem, we could benefit from recognizing that the reverse view is equally plausible. According to this reverse view, which the authors call hindsight, therapists, unaware of it themselves, first come up with interventions and then, in hindsight, create explanations or particular ways of understanding problems in order to make their interventions seem rational and justifiable. A number of factors influencing therapists' choice of interventions are explored. Finally some potential advantages of the hindsight view are examined.     

Pastoral counseling with alcoholics and their families

The pastor is often in contact with the alcoholic and his or her family. Providing help to alcoholics and their families is a spiritual, humanistic, and therapeutic challenge. Recent developments have favored a family systems orientation to working with alcoholic families. This orientation acknowledges the family as contributor to maintaining alcoholic behavior and includes the family in treatment. Specific family systems concepts are discussed and how they relate to the dysfunctional unit which houses an alcoholic. Implications for pastors and specific role definitions are explored. Krebs' therapeutic model is expanded to: 1) evaluate, 2) support, 3) refer, and 4) support, as appropriate for the pastor working with alcoholics and their families.     

Motivated changes of auditory sensitivity in a simple detection task

Recently both neurophysiological and psychophysical theories have suggested that the sensitivity of receptors, or of the whole organism, may change through “efferent control” or as a result of “motivation.” A psychophysical method has been devised to investigate changes in a listener’s ability to detect signals in a noisy background, which are elicited “on demand” by the E, and when the time course of the changes may be in the order of seconds rather than minutes orhours. Observed effects, which are consistent with the hypotheses of active control of sensitivity, are found to be orderly but quite small, generally less than that associated with a 1–2 dB increase in the level of a tonal signal. While the average increment in performance is thus slight, it is found that the variance between Ss is significantly reduced when strong motivating stimuli are introduced. This reduction in variance may reflect an upper limit on the performance of real listeners, which might be fruitfully compared with the theoretical limits proposed in the theory of signal detectability.     

Effects of discriminability and irrelevant information on absolute judgments’

The effects of irrelevant information (0, 1, 2, or 3 bits stimulus) on absolute judgments of size were measured at different levels of discrimination difficulty. The stimuli were 7 small circular spots of light of different sizes, selected from an eaual-discriminability scole, and arranged into 6 pairs that represented different levels of stimulus dissimilarity. Three of the pairs comprised a low-dissimilarity (LD) subgrouping in which different lepels of dissimilarity and discriminability were confounded, whereas the remaining three pairs comprised a high-dissimilarity (HD) subgrouping in which different levels of dissimilarity occurred at a single high level of discriminability. Different colors were used to provide the four levels of irrelevant information; 240 Ss (10 in each of the 24 experimental conditions) made absolute judgments of size under the classical procedure for the method of single stimuli. Separate analyses of errors, reaction times, and rates of information transmission indicated that irrelevant information had an increasingly detrimental effect on absolute judgments as discrimination difficulty was increased (in the LD subgroup), but essentially no effect where discriminations were easily modefin the HD subgroup).