Fluctuating dynamics of perceived exertion in constant-power exercise

ObjectivesTo reveal and study the fluctuating dynamics of perceived exertion (PE) during constant-power exercise performed under different conditions (duration, intensity, and termination).DesignA pilot and two subsequent experimental studies were performed. The studies consisted of manipulating workload and measuring fluctuating perceived exertion dynamics throughout the cycling task.MethodsIn a pilot study Borg's rating of perceived exertion (RPE) was measured every 15 s in 2 groups of 9 participants each (using RPE 6-20 and CR10 scales, respectively) cycling at heavy intensity until volitional exhaustion. The percentage of participants alternating increased and decreased RPE values (fluctuating dynamics) was calculated. In 2 subsequent experiments PE changes (increase/decrease perceptions) were reported when occurring in 2 groups of 13 participants cycling at a moderate intensity for 30 and 60 min, respectively (Experiment 1), and in another group of 12 participants cycling at heavy intensity until volitional exhaustion (Experiment 2). The individual time series of “increase”/“decrease” reports were divided into 5 non-overlapping temporal windows, and the percentages of “PE increase” were calculated for each window.ResultsIn the pilot study 66.6% (RPE 6-20 group) and 33.3% (CR10 group) of the participants showed an RPE fluctuating dynamics during the exercise. However, all participants showed a clear PE fluctuating dynamics during the moderate and heavy intensity exercises performed in Experiment 1 and Experiment 2, respectively. Nevertheless, a transition towards a PE non-fluctuating dynamics (dominated by “PE increase” reports) was noticed in Experiment 2 while approaching volitional exhaustion.ConclusionsPE seems to have a dominant fluctuating dynamics during constant-power cycling performed under different conditions (duration, intensity, and termination) that changes towards a non-fluctuating dynamics when approaching the volitional exhaustion point.     

Neuropsychology of mildly disabled patients with relapsing-remitting multiple sclerosis

Previous papers have mainly demonstrated the presence of cognitive impairment in patients with multiple sclerosis (MS), these changes have been traditionally associated with the later stages of the disease. In the current study, a comprehensive neuropsychological battery was administered to 216 relapsing-remitting MS patients with mild clinical disability (EDSS相似文献   

The role of affordances in inhibition of return

Inhibition of return (IOR) is a response delay that occurs when the target is preceded by an irrelevant stimulus (cue) at the same location. IOR can be object based, as well as location based. The aim of the present study was to investigate the role of the pragmatic features of a visually presented object in causing IOR. Two experiments were carried out using different objects as stimuli, for which the graspable part (affordance) was clearly defined. The presentation of a whole object, with the part commonly used to grasp it located below, served as a cue. The presentation of either the graspable or the ungraspable part of the cued or uncued object served as the target Results showed that responses were slower when the graspable part was shown in the cued location than when the ungraspable part was shown in the same location. The effect was apparently linked to the kind of action necessary to grasp an object.     

Consensual validity parameters of the Zuckerman-Kuhlman personality questionnaire: evidence from self-reports and spouse reports

One way of validating questionnaire responses is correlating them with ratings made by external assessors who know the ratee well: This is known as consensual validity. In this study, we assessed the consensual validity of the Zuckerman-Kuhlman Personality Questionnaire (ZKPQ; Zuckerman, 2002; Zuckerman, Kuhlman, Joireman, Teta, & Kraft, 1993). A multitrait-multimethod matrix of self-reported and spouse reported personality ratings was used to establish convergent and discriminant validity by means of Campbell and Fiske's (1959) evaluative criteria. Self-reports of 86 men and 85 women were correlated with their spouses' reports. Intraclass correlations ranged from .47 to .63 for the 5 dimensions, providing strong evidence of convergent and discriminant validity. The results obtained favor the use of the ZKPQ as a valid self-report measure of personality traits.     

State-trait anxiety and motocross performance

The prediction from state-trait theory that subjects low in anxiety will perform better than highly anxious subjects on a more difficult task was tested on a motocross competition. We analyzed the relationships among the entire rank order of finish and state and trait anxiety measured by State-Trait Anxiety Inventory for 32 motocross riders (males whose age ranged from 16 to 27 yr.) participating in a national competition in Italy. A negative correlation between performance (measured by rank at the finish of the competition) and state anxiety was noted. The r for state and trait anxiety scores was also negative, but that between performance and trait anxiety was nonsignificant. Additional studies of high level sport competition will provide data relevant to planning interventions to control athletes' anxiety.     

Asymmetries in processing horizontal and vertical dimensions

The aim of this study was to determine whether the referential term on the horizontal dimension corresponds to the dominant hand and whether the referential term on the vertical dimension is independent of handedness. In order to verify the hypothesis, right-handers, left-handers, and ambidextrous subjects were required to verify and falsify statements including the words ABOVE and BELOW and the words LEFT and RIGHT. The results showed that right-handers were faster in verifying and falsifying the statements containing the term RIGHT, whereas left handers were faster in verifying and falsifying those containing the term LEFT. Ambidextrous subjects, however, showed no sign of asymmetry in the positional judgments of stimuli along the horizontal dimension. By contrast, right-handers, left-handers, and ambidextrous subjects were equally faster in verifying and falsifying the statements containing the term ABOVE than the statements containing the term BELOW. The relation between the positive term on the horizontal dimension and the dominant hand can be explained by the fact that, in the absence of any asymmetries in the physical world, the dominant hand can furnish a natural reference direction for judgments related to this dimension.     

Ongoing postdivorce conflict and child disturbance

This paper reports on the disturbed behavior of children who are subject to entrenched parental disputes over their custody and care after separation and divorce. The 56 children who varied in racial and socioeconomic origin were 4 to 12 years old at entry into the study. They were assessed at two points: at the time of the custody dispute and 2.5 years later. The extent of the child's involvement in the dispute and the amount of role reversal between parent and child predicted total behavior problems and aggression at the time of the legal dispute. These same factors, together with the rate of verbal and physical aggression between parents, predicted total behavior problems, depression, withdrawn/uncommunicative behavior, somatic complaints, and aggression at the 2-year follows-up. There were no main effects for sex and age. However, at the 2-year mark, girls in high-conflict families were more depressed and withdrawn, and older children in high-conflict situations had more somatic complaints and were more aggressive. The findings are considered in the light of a number of etiological mechanisms by which parental conflict affects children. Funds for the clinical work were provided by the Zellerbach Family Fund and the San Francisco Foundation the Van Loben Sels Foundation, and the Morris Stulsaft Foundation. Support for the first author was provided by an NIMH Fellowship in Social Structure, Personality and Mental Illness, Department of Sociology, University of California, Berkeley.     

Attention shifts produce spatial stimulus codes

Summary In the Simon task the spatial position of the stimulus, though task irrelevant, influences speed of response. We (Umiltà & Nicoletti, 1992) proposed that the orienting of attention to the imperative stimulus produces a Stroop-like interference. This paper reports the results of three experiments that provide empirical support for two predictions of this hypothesis. One is that the stimulus spatial code is formed with relation to the position to which attention is directed. The other prediction is that the Simon effect is obtained on condition that attention can orient to the stimulus.Some of the results of Experiments 1 and 2 were reported briefly in Umiltà and Nicoletti (1992)     

Inhibitory and facilitatory effects of cue onset and offset

The response speed to a visual target is modulated by the position of previous events (cues) even if their position is not predictive of the target position. The modulation has been considered biphasic, with an early facilitatory and a later inhibitory component. We conducted three experiments that investigated the importance of the onset and offset features of the cue for the facilitatory and inhibitory effects and estimated their separate and joint effects. The two possible target locations, one in the right and one in the left visual field, were indicated by two empty boxes, and the cue consisted of the onset and/or offset of an arrowhead located just under one of the two boxes. Different time intervals were used between cue and target. Subjects were instructed to ignore the cue and to respond to the target (a cross inside one of the two boxes). The data showed only consistent effects of inhibition (inhibition of return) with the long intervals, but the pattern was different depending on the cue type. The amount of inhibition was much greater when the onset of the cue was followed by its offset. Apparently, inhibition of return depended on the dynamic changes of the cue. Received: 23 October 1996 / Accepted: 3 June 1997