Anxiety induced by cardiac perceptions in patients with panic attacks: a field study

In panic disorder bodily sensations appear to play an important role as a trigger for anxiety. In our psychophysiological model of panic attacks we postulate the following vicious circle: individuals with panic attacks perceive even quite small increases in heart rate and interpret these changes as being catastrophic. This elicits anxiety and a further increase in heart rate. To evaluate this model we conducted a field study of 28 subjects with panic attacks and 20 healthy controls. A 24 hr ambulatory ECG was recorded and the subjects were instructed to report any cardiac perceptions during this period and to rate the anxiety elicited by these perceptions. The incidence of cardiac perceptions was about the same in both groups, but only subjects with panic attacks reported anxiety associated with such perceptions. Analysis of the ECGs revealed that in both groups heart rate accelerations preceded cardiac perceptions. Following cardiac perceptions, the healthy controls showed a heart rate deceleration, whereas the subjects with panic attacks had a further acceleration. This heart rate increase after cardiac perceptions was positively related to the level of anxiety elicited by the perceptions. These results provide clear evidence in support of the vicious circle model of panic attacks.     

After-contraction phenomenon: influences on performance and learning

Three experiments investigated the influence of an after-contraction phenomenon on the performance and learning of a dynamic force-production task. The after-contraction effect refers to an involuntary potentiation (induced by a sustained precontraction) that is thought to summate with voluntary motor commands to bias subsequent responding. The precontraction involved a brief (20 s) static contraction. The subsequent influence of the precontraction on a dynamic force-production task was assessed. Experiments 1 and 2 were aimed at demonstrating the direct impact of the precontraction intensity on the magnitude and decay of the after-contraction effect. The results indicated that as the intensity of the precontraction increased, the magnitude of the induced bias increased. In Experiment 3, the indirect influence on subsequent retention of varying the precontraction intensity during acquisition was investigated. The results indicated that the performance of subjects experiencing varying precontraction intensities during acquisition was inferior to that of subjects experiencing a constant precontraction intensity, but the performance of the varied precontraction intensities group was superior on the test of retention. It is noted that the paradoxical reversal from acquisition to retention is similar to that found in contextual interference experiments and may arise from similar mechanisms.     

Classifying by dimensions and reading: a comparison of the auditory and visual modalities

Children have difficulty learning to read alphabetic writing systems, in part, because they have difficulty segmenting spoken language into phonemes. Young children also have difficulty attending to the individual dimensions of visual objects. Thus, children's early difficulty in reading may be one sign of a general inability to selectively attend to the parts of any perceptual wholes. To explore this notion, children in kindergarten through fourth grade (Experiments 1, 3, and 4) and adults (Experiment 2) classified triads of spoken syllables and triads of visual objects. Classifying speech by common parts was positively related to reading and spelling ability (Experiments 1 and 4), but usually not to classifying visual stimuli by common parts under free classification instructions (Experiments 1 through 3). However, classification was more consistent across the visual and auditory modalities when the children were told to classify based on a shared constituent (Experiment 4). Regardless of instructions, performance on the visual tasks did not usually relate to reading and spelling skill. The ability to attend selectively to phonemes seems to be a "special" skill--one which may require specific experiences with language, such as those involved in learning to read an alphabetic writing system.     

The relationship between trauma and financial and physical well-being among Cambodians in the United States.

This study focused on the relationship between trauma and financial and physical well-being of Cambodian refugees in the United States. Trauma was defined by three variables: whether or not trauma had been experienced in Cambodia, the number of traumas experienced, and the number of years spent in refugee camps. It was hypothesized that these trauma variables would predict financial and physical health among Cambodians in the United States. A discriminant analysis showed significant relationships between the trauma variables and current employment status, and multiple regression analyses showed that trauma predicted income and physical health.     

Is object texture a constraint on human prehension?: kinematic evidence

The present experiment determined whether object texture influenced the transport and grasp components of human prehension. Infrared markers placed on the index finger, thumb, and wrist were recorded using a WATSMART system. The test objects were cylindrical dowels (103 mm high, 25 mm diameter, and 150 g in weight) of various surface materials (plain metal, coated with Vaseline, and covered with coarse sandpaper). Only temporal kinematic measures were affected by texture: Movement time (ms), time after peak deceleration (ms), percentages of movement time following maximum aperture, velocity, and deceleration were all significantly greater for the slippery dowel than the normal and rough dowels. Results indicated that the increased time associated with the slippery dowel could be explained entirely by increased time between contact with the dowel and dowel lift. Thus, these results are like those of Weir, MacKenzie, Marteniuk, Cargoe, and Frazer (1991), in which object weight was shown not to affect the free-motion phase, which includes the transport and grasp components of prehension. It appears that intrinsic object properties like weight and texture affect only the finger-object interaction phase of prehension; subsequent research is needed to dissociate inertial and surface friction effects while in contact with objects     

Perceived Control, Drive for Thinness, and Food Consumption: Anorexic Tendencies as Displaced Reactance

Although loss of perceived control has been implicated in the development of eating disorders, previous research has not directly tested the relationship between perceived control and food consumption. This study investigated the hypothesis that individuals with anorexic tendencies react to low perceived control by restricting food intake as a means of regaining a sense of control. Forty female undergraduates who scored either low or high on the Drive for Thinness Scale (Garner & Olmsted, 1984) were led to believe they would be participating in two separate studies. Perceived control was experimentally manipulated such that half of the subjects experienced low control and half experienced high control over a social situation. Under the guise of a second experiment, subjects tasted breakfast cereals and completed measures relevant to eating and body image. Results showed that subjects who were high in drive for thinness (DT) who experienced low control ate less sweetened cereal and planned to eat less at dinner than high DT subjects who experienced high control. Low DT subjects were unaffected by the control manipulation. The results are discussed in terms of displaced reactance.     

Test of structural relationships within a proposed exercise and self-esteem model

This study tested structural relationships within a model proposed to explain the manner in which self-esteem changes are associated with exercise experiences. As initially assessed by self-efficacies (EFFs) specific to physical tasks within a training program, we postulated that competence can generalize to feelings of global self-esteem (SE) through an intervening construct of perceived physical competence (PC). Three measures of EFF and two each of PC and SE were administered to 145 people in their mid- to late adulthood. Confirmatory factor analysis examined orthogonal and oblique versions of three measurement models and identified three distinct but correlated factors, each assessed by its hypothesized indicators. Alternative structural equation models were specified and tested using both normal and nonnormal estimation procedures. The proposed model provided the most parsimonious fit and explained 29% of the variance in SE. Confirmation of its structural relationships provides preliminary validity for model use in examining the manner in which exercise experiences influence levels of self-perception.     

Parental authority questionnaire

A questionnaire was developed for the purpose of measuring Baumrind's (1971) permissive, authoritarian, and authoritative parental authority prototypes. It consists of 30 items per parent and yields permissive, authoritarian, and authoritative scores for both the mother and the father; each of these scores is derived from the phenomenological appraisals of the parents' authority by their son or daughter. The results of several studies have supported the Parental Authority Questionnaire as a psychometrically sound and valid measure of Baumrind's parental authority prototypes, and they have suggested that this questionnaire has considerable potential as a valuable tool in the investigation of correlates of parental permissiveness, authoritarianism, and authoritativeness.     

Personality and susceptibility to positive and negative emotional states

Gray's (1981) theory suggests that extraverts and neurotics are differentially sensitive to stimuli that generate positive and negative affect, respectively. From this theory it was hypothesized that efficacy of a standard positive-affect induction would be more strongly related to extraversion than to neuroticism scores, whereas efficacy of a standard negative-affect induction would be more strongly related to neuroticism scores. Positive and negative affect was manipulated in a controlled setting, and the effectiveness of the mood induction was assessed using standard mood adjective rating scales. Results are consistent with the hypothesis that neurotic Ss (compared with stable Ss) show heightened emotional reactivity to the negative-mood induction, whereas extraverts (compared with intraverts) show heightened emotional reactivity to the positive-mood induction. Results corroborate and extend previous findings.     

Coping with health threat: social influence processes in reactions to medical test results

In a laboratory experiment, undergraduate subjects tested positive for an enzyme deficiency they believed to be a risk factor for pancreatic disorders. All Ss were tested with a confederate who received a positive or negative test result. For half the Ss, the confederate expressed a minimizing appraisal of the deficiency's seriousness. Although Ss' concern about the test result was significantly reduced by what the confederate said, behavioral intentions were determined by the confederate's diagnostic status. The effect of the confederate's diagnostic status on intentions was mediated by Ss' perceptions of the deficiency's prevalence. The results support Leventhal's self-regulation theory and demonstrate that the opinions and health characteristics of comparison others have differential effects on cognitive, emotional, and behavioral aspects of coping with a health threat.