The variation of hand steadiness with physical stress

The performance of 12 subjects in a hand steadiness task was compared at different work loads. Hand steadiness expressed in the form of values of hand shakiness was found not to increase linearly with work intensity. On the contrary, the relation between hand shakiness and activation level, induced by physical work, was found to be positively accelerated by an exponent of 1.6. Subjective effort measured by a ratio estimation method grew, likewise, according to a positively accelerating function with an exponent of about 1.6, while subjective effort according to the "RPE" category scale like hear rate grew linearly with work load.     

Preferred hand and steadiness of reaction time.

RT and its left/right difference of both biceps muscles were measured by electromyogram (EMG) in the bilateral simultaneous flexion of elbows using 11 left- and 13 right-handed subjects under four conditions which were combinations of two factors; warning signal; presence or absence of a fore-period, and position of limbs; elbow 90 degrees or 135 degrees. EMG-RT and its left/right difference were influenced by these factors. The effects of warning and position of limbs were not the same on the preferred and non-preferred hands. It was assumed that EMG-RTs of biceps in the preferred hand were less influenced by these experimental conditions.     

Effects of aging on the suprathreshold responses to vibration

The psychophysical responses to vibration of two age groups (22 or 25 and 66 years) were compared for two tasks using suprathreshold levels of vibrotactile stimulation. At a vibration frequency of 25 Hz, the two age groups gave similar curves of subjective magnitude determined by the method of absolute magnitude estimation. At 250 Hz, the curve of the older group showed no recruitment over low levels of intensity. Instead, their magnitude estimates were depressed over the entire range of intensities. Sensory persistence, measured by a matching procedure, was more marked in the older group.     

Effects of electromyostimulation on knee extensors and flexors strength and steadiness in older adults

It is known that electromyostimulation (EMS) alone or superimposed over voluntary contraction (EV) can effectively improve muscle strength. However, the effect of this type of training on the ability to control force production at submaximal levels is unknown. The authors examined the effects of EV training on steadiness in force production of knee extensors and flexors in older adults. Forty participants, including 20 men and 20 women, 60-77 years of age, were randomly allocated into a control group (CG) and an electromyostimulation superimposed over voluntary contraction (EVG) group. The EVG performed 30 bilateral isometric knee extension and flexion contractions per session, 3 training sessions per week, for 6 weeks. The variations in force production, expressed in absolute (standard deviation [SD]) and relative (coefficient of variation [CV]) terms, were assessed in isometric contractions at 5%, 15% and 25% maximal voluntary contraction (MVC) levels. Results indicated that MVC increased in knee extension and flexion in EVG (p < .05) after the training; steadiness CV also improved at 15% MVC in knee flexion (p < .05) but no significant changes were found in knee extension and steadiness SD. The training-induced changes in MVC were not correlated to steadiness CV that might indicate different mechanisms underlying these adaptations.     

Effects of escalated exposure to information on accuracy of personality judgment

In an investigation of the effects of increasing exposure to information on accuracy of personality trait judgments, judges rated a single target on three successive occasions, each of which involved the introduction of a novel piece of personal information. Varying the order in which types of information were presented allowed us to jointly examine the effects of information quality and quantity on accuracy in personality judgment. We found that (a) in general, more information led to higher accuracy, (b) some types of information led to greater gains in distinctive or normative accuracy, and (c) introduction of lower quality information did not negatively affect accuracy.     

Effects of exposure to alcohol‐related cues on racial discrimination

Prior research has shown that exposure to alcohol‐related images exacerbates expression of implicit racial biases, and that brief exposure to alcohol‐related words increases aggressive responses. However, the potential for alcohol cue exposure to elicit differential aggression against a Black (outgroup) relative to a White (ingroup) target—that is, racial discrimination—has never been investigated. Here, we found that White participants (N = 92) exposed to alcohol‐related words made harsher judgments of a Black experimenter who had frustrated them than participants who were exposed to nonalcohol words. These findings suggest that exposure to alcohol cues increases discriminatory behaviors toward Blacks.     

Effects of exposure to sexist humor on perceptions of normative tolerance of sexism

The results of an experiment supported the hypotheses that (1) for men high in hostile sexism, exposure to sexist humor creates a perceived social norm of tolerance of sexism relative to exposure to nonhumorous sexist communication or neutral humor, and (2) due to this ‘relaxed’ normative standard in the context of sexist humor, men high in hostile sexism anticipated feeling less self‐directed negative affect upon imagining that they had behaved in a sexist manner. Finally, exposure to sexist humor did not affect the evaluative content of men's stereotypes of women relative to exposure to neutral humor or nonhumorous sexist communication for participants high or low in hostile sexism. Copyright © 2001 John Wiley & Sons, Ltd.     

Effects of exposure to sex-stereotyped video game characters on tolerance of sexual harassment

The violent video game literature has previously not extended to the domain of violence against women. The current investigation tested the effects of exposure to sex-typed video game characters versus images of professional men and women on judgments and attitudes supporting aggression against women. Results showed experimental effects of short-term exposure to stereotypical media content on sexual harassment judgments but not on rape myth acceptance. A significant interaction indicated that men exposed to stereotypical content made judgments that were more tolerant of a real-life instance of sexual harassment compared to controls. Long-term exposure to video game violence was correlated with greater tolerance of sexual harassment and greater rape myth acceptance. This data contributes to our understanding of mass media’s role in socialization that supports violence against women.     

Effects of homogeneous and variable exposure on magnitude of adaptation to optical tilt

Repeated exposure to hallway exploration, alternated with periods of either watching the active hand or exploring a different set of hallways, maintains increasing visual adaptation beyond the point in time at which previous studies using homogeneous exposure have found such visual shift (VS) to be asymptotic. Experiment 1 established that this alternation-repetition effect does not depend on an actual change in task (hall to hand) but also occurs when the task context alone is changed (hall to hall). Experiment 2 compared variable (hall-to-hall) exposure with homogeneous (hall) exposure, showing that variable exposure removes the usual limit on adaptation. In both experiments, proprioceptive shift (PS) and total negative aftereffect (NA) both tended to be less than VS, producing substantial overadditivity (i.e., VS + PS greater than NA). General requirements for an attentional explanation of the alternation-repetition effect are outlined, and possible explanations of overadditivity consistent with the linear model are discussed.     

Effects of imaginal exposure to feared disasters in obsessive-compulsive checkers

The combined effects of imaginal exposure to feared catastrophes and in vivo exposure to external stimuli were compared with the effects of in vivo exposure alone in 15 obsessive-compulsives with checking rituals. The first group received 90 min of uninterrupted exposure in imagination, which concentrated mainly on disastrous consequences, followed by 30 min of exposure in vivo to stimuli-situations which triggered rituals. The second group was given 2 hr of exposure in vivo only. Both groups were prevented from performing rituals. Treatment consisted of 10 daily sessions within a 2 week period.Assessments were conducted before and after treatment and at follow-up ranging from 3 months to 2.5 yr with a mean of 11 months. At post-treatment both groups improved considerably and did not differ. But at follow-up those who received imaginal and in vivo exposure maintained their gains, whereas the group who were treated by exposure in vivo alone evidenced partial relapse on four of the six dependent measures. The results tend to indicate that a closer match between a patient's internal fear model and the content of exposure enhances long term treatment efficacy.     

The role of motion platform on postural instability and head vibration exposure at driving simulators

This paper explains the effect of a motion platform for driving simulators on postural instability and head vibration exposure. The sensed head level-vehicle (visual cues) level longitudinal and lateral accelerations (a_x,sensed = a_{x_head} and a_y,sensed = a_{y_head}, a_yv = a_{y_veh} and a_yv = a_{y_veh}) were saved by using a motion tracking sensor and a simulation software respectively. Then, associated vibration dose values (VDVs) were computed at head level during the driving sessions. Furthermore, the postural instabilities of the participants were measured as longitudinal and lateral subject body centre of pressure (X_CP and Y_CP, respectively) displacements just after each driving session via a balance platform. The results revealed that the optic-head inertial level longitudinal accelerations indicated a negative non-significant correlation (r = −.203, p = .154 > .05) for the static case, whereas the optic-head inertial longitudinal accelerations depicted a so small negative non-significant correlation (r = −.066, p = .643 > .05) that can be negligible for the dynamic condition. The X_CP for the dynamic case indicated a significant higher value than the static situation (t(47), p < .0001). The VDV_x for the dynamic case yielded a significant higher value than the static situation (U(47), p < .0001). The optic-head inertial lateral accelerations resulted a negative significant correlation (r = −.376, p = .007 < .05) for the static platform, whereas the optic-head inertial lateral accelerations showed a positive significant correlation (r = .418, p = .002 < .05) at dynamic platform condition. The VDV_y for the static case indicated a significant higher value rather than the dynamic situation (U(47), p < .0001). The Y_CP for the static case yielded significantly higher than the dynamic situation (t(47), p = .001 < 0.05).     

Effects of recent exposure to a conditioned stimulus on extinction of Pavlovian fear conditioning

In six experiments we studied the effects of a single re-exposure to a conditioned stimulus (CS; "retrieval trial") prior to extinction training (extinction-reconsolidation boundary) on the development of and recovery from fear extinction. A single retrieval trial prior to extinction training significantly augmented the renewal and reinstatement of extinguished responding. Augmentation of recovery was not observed if the retrieval and extinction training occurred in different contexts. These results contrast with those reported in earlier papers by Monfils and coworkers in rats and by Schiller and coworkers in humans. We suggest that these contrasting results could depend on the contrasting influences of either: (1) occasion-setting contextual associations vs. direct context-CS associations formed as a consequence of the retrieval trial or (2) discrimination vs. generalization between the circumstances of conditioning and extinction.     

Effects of exposure to psychophysical scaling on lingual vibrotactile magnitude estimation and magnitude production

The purpose of the present study was to determine if the results obtained by the scaling methods of magnitude estimation and magnitude production could be influenced by providing subjects with prior exposure to psychophysical scaling in the form of magnitude estimation or magnitude production. Group 1 (n = 10, Mage = 21.1 yr.) performed lingual vibrotactile-magnitude estimation followed by lingual vibrotactile magnitude production. Group 2 (n = 10, Mage = 19.7 yr.) performed lingual vibrotactile-magnitude production (using the magnitude-estimation responses provided by Group 1), followed by lingual vibrotactile-magnitude estimation. For the magnitude estimations there was no over-all statistically significant difference between the two groups, but there was for the magnitude-production values. Magnitude-estimation scaling was apparently not influenced by prior exposure to magnitude production, while magnitude-production scaling was influenced by prior exposure to magnitude estimation. The results are discussed in terms of how subjective scaling behavior in psychophysical experimentation may be influenced by the interaction between an absolute internal scaling mechanism and parameters set by the experimenter, such as scaling method and range of stimulus intensity.