Role of the sympathetic nervous system in cerebrovascular responses to air-jet stress in rats

This study examined the role of sympathetic nerves in the control of cerebral hemodynamics during air-jet stress. In adult male Sprague-Dawley rats, blood flow velocity (pulsed Doppler) was measured in both internal carotid arteries 1 week after excision of one superior cervical ganglion. Blood pressure (BP) and carotid blood flows (CBFs) were simultaneously recorded during exposure to air-jet stress. In 5 out of 13 rats, stress was applied after β(2)-adrenoceptor blockade with ICI 118551 (0.4 mg/kg, then 0.2 mg/kg/h, i.v). Stress evoked an immediate rise in BP, CBFs, and vascular conductances. Vasodilatation was much larger on the denervated side than on the intact side (mean ± SEM: 78 ± 7 versus 19 ± 4%; P < 0.02) and lasted about 10 s. Thereafter, blood flows returned to or near normal and showed parallel variations while BP remained elevated. There was, therefore, a net vasoconstriction on both sides. In ICI 118551-treated rats, the initial vasodilatation was not significantly reduced on the denervated side (64 ± 4%), but the subsequent vasoconstriction was enhanced (P < 0.05) on both sides. In conclusion, air-jet stress evokes an immediate, short-lasting vasodilatation through a mechanism unrelated to β(2)-adrenoceptor stimulation. Sympathetic nerves powerfully limit this phenomenon, and thus contribute to protect the cerebral circulation from stress-induced BP surges.     

Development and evaluation of the psychometric properties of the parents' Perceptions of Physical Activity Importance and their Children's Ability Questionnaire (PPPAICAQ)

ObjectivesThe purpose of the present study was to develop and psychometrically evaluate a new measure of parental perceptions grounded in the Eccles' parental socialization framework: the Parents' Perceptions of Physical Activity Importance and their Children's Ability Questionnaire (PPPAICAQ).DesignCross-sectional with self-reported questionnaires.MethodThe total sample comprised 1100 parents of children (6–11 years old) and was randomly divided in third (one calibration and two validation samples). Data were analyzed with reliability, confirmatory factor analyses (CFA), multi-group CFAs as well as with correlational analyses.ResultsResults of the initial confirmatory factor analyses (CFAs) of the 2-factor 12-item model on the calibration sample resulted in a poor fit to the data. Re-estimation of the PPPAICAQ resulted in the deletion of 4 initial items. The 2-factor 8-item model revealed a good fit to the data for the three samples. Results of two multiple-group CFAs showed that the final model was partially invariant across the father and mother as well as the boy and girl samples. The patterns of relationships between parents' motivation, parents' support and the PPPAICAQ subscales provided evidence for the criterion-related validity of the PPPAICAQ.ConclusionThis study provided support for the reliability and validity of the PPPAICAQ. The PPPAICAQ is an instrument that will be useful for theoretically-driven research on parental socialization influence on children’ PA.     

Prospective strategies underlie the control of interceptive actions

The purpose of this study was to test whether a constant bearing angle strategy could account for the displacement regulations produced by a moving observer when attempting to intercept a ball following a curvilinear path. The participants were asked to walk through a virtual environment and to change, if (deemed) necessary, their walking speed so as to intercept a moving ball that followed either a rectilinear or a curvilinear path. The results showed that ball path curvature did indeed influence the participants' displacement kinematics in a way that was predicted by adherence to a constant bearing angle strategy mode of control. Velocity modifications were found to be proportional to the magnitude of target curvature with opposing curvatures giving rise to mirror displacement velocity changes. The role of prospective strategies in the control of interceptive action is discussed.     

The use of Tholos software for combining measures of mental workload: Toward theoretical and methodological improvements

Mental workload is a concept central to a range of disciplines (including cognitive psychology and ergonomics) that has given rise to various theoretical and methodological debates. As a result, researchers have used a number of techniques for measuring mental workload. Traditionally, three categories of measurement technique have been recognized: performance measures (e.g., the dual-task paradigm), subjective measures (e.g., rating scales), and physiological measures (e.g., heart, respiration, and blink rates). Each technique has advantages and limitations; however, some limitations may prevent an accurate evaluation of the mental workload. In this article, we focus on the benefits of combining multiple measures of mental workload. However, because combining several techniques is a very complex process, we have developed the Tholos software in an attempt to reduce this complexity. This software package uses measures from each of the three categories: a dual-task paradigm with auditory signals; the National Aeronautics and Space Administration task load index (NASA-TLX) scale and its simplified version, the “raw” task load index (RTLX); and physiological (such as pupil-dilation) measurements with which our software can merge results from the dual-task paradigm. To illustrate the benefits of using Tholos, we describe a puzzle-solving experiment in which we combined multiple measures of mental workload. The results indicate the importance of combining multiple measures to build upon the theoretical and methodological foundations of mental workload.     

The mediating role of positive and negative affect in the situational motivation-performance relationship

Based on self-determination theory (Deci and Ryan in Intrinsic motivation and self-determination in human behavior. Plenum Publishing Co., New York, 1985) and the broaden-and-build theory (Fredrickson in Am Psychol 56:218–226, 2001), the purpose of the present research was to propose and test an integrative model on the role of positive and negative affect as mediators of the situational motivation-performance relationship. Specifically, the hypothesized model posits that autonomous motivation predicts positive affect, while controlled motivation and amotivation both lead to negative affect. In addition, amotivation negatively predicts positive affect. In turn, positive and negative affect positively and negatively predict performance, respectively. The model was confirmed in three studies using correlational (Studies 1 and 2) and experimental designs (Study 3) with a cognitive task (anagrams). In addition, the role of individual differences (Study 2) and situational factors (Study 3) as triggers of the “Motivation-Affect-Performance” sequence was confirmed. Theoretical implications and directions for future research are discussed.     

Being moved

In this paper, we argue that, barring a few important exceptions, the phenomenon we refer to using the expression “being moved” is a distinct type of emotion. In this paper’s first section, we motivate this hypothesis by reflecting on our linguistic use of this expression. In section two, pursuing a methodology that is both conceptual and empirical, we try to show that the phenomenon satisfies the five most commonly used criteria in philosophy and psychology for thinking that some affective episode is a distinct emotion. Indeed, being moved, we claim, is the experience of a positive core value (particular object) perceived by the moved subject as standing out (formal object) in the circumstances triggering the emotion. Drawing on numerous examples, we describe the distinctively rich phenomenology characteristic of the experience as well as the far-reaching action-tendencies and functions associated with it. Having thus shown that the candidate emotion seem to satisfy the five criteria, we go on, in section three, to compare it with sadness and joy, arguing that it should not be confused with either. Finally, in section four, we illustrate the explanatory power of our account of “being moved” by showing how it can shed light on, and maybe even justify, the widespread distrust we feel towards the exhibition of ‘sentimentality’. On the whole and if we are right, we have uncovered an emotion which, though never or rarely talked about, is of great interest and no small importance.