Disappearance of afterimages at 'impossible' locations in space

An eccentrically positioned afterimage, viewed in the dark, will disappear if the eye is positioned so that the afterimage now projects to a more extreme location relative to straight ahead. It was found that the afterimage disappeared when it projected to a location which corresponded to the edge of the visual field defined by the brow, cheek, and nose. This suggests that visibility of stimuli from those retinal regions shadowed by the head is influenced by eye-position information.     

Motivation and anxiety for dental treatment and dental attendance: The roles of the locus of causality personality and treatment styles

The purpose of the present study was to test a self-determination theory model with the following hypotheses: (1) Patients’ autonomous causality personality orientation and oral health care professionals’ autonomy-supportive treatment styles, as perceived by patients, would both be positively indirectly associated with dental attendance through patients’ autonomous motivation for dental treatment. (2) Patients’ controlled causality personality orientation and oral health care professionals’ controlling treatment styles, as perceived by patients, would both be positively indirectly associated with avoidance of making a dental clinic appointment through patients’ anxiety for dental treatment. A sample size of about 200 patients was estimated to be acceptable in detecting moderate effect sizes (independent variables: 5–6; power: .80; p < .05). Student patients (N = 226) responded to a survey with validated questionnaires. Using LISREL, both hypotheses were supported. In addition, patients’ perception of a controlling treatment style moderated the controlled personality—dental anxiety relation, so that a lower controlling treatment style mitigated dental anxiety substantially among patients with a high control orientation. Effect sizes were moderate to large. Analyses (Z-scores) also revealed that the autonomous personality is more strongly linked to situational autonomous motivation than situational autonomy support, whereas a controlled personality and a perceived controlling treatment style are equally and significantly associated to dental anxiety. Both patient personalities and oral health care professionals’ treatment styles are substantially linked to autonomous motivation and anxiety for dental treatment, which are relatively strongly associated with dental attendance and avoiding dental clinic appointments, respectively.     

Aging Affects the Ability to Process the Optic Flow Stimulations: A Functional Near-Infrared Spectrometry Study

Abstract

Optic flow (OF) has been utilized to investigate the sensory integration of visual stimuli during postural control. It is little known how the OF speed affects the aging brain during the sensory integration process of postural control. This study was to examine the effect of OF speeds on the brain activation using functional near-infrared spectroscopy (fNIRS) and postural sway between younger and older adults. Eleven healthy younger adults (5M/6F, age 22?±?1-year-old) and ten healthy older adults (4M/6F, age 71?±?5-year-old) participated in this study. A virtual reality headset was used to provide the OF stimulus at different speeds. A forceplate was used to record the center-of-pressure to compute the amplitude of postural sway (peak-to-peak). Compared with younger adults, older adults showed significantly increased activation in the OF speed of 10?m/s and decreased activation in the OF speed of 20?m/s in the left dorsolateral prefrontal cortex. Older adults also showed decreased activation in the left temporoparietal region (VEST) in the OF speed of 20?m/s. A significant difference in peak-to-peak was found between groups. Our results indicated that age might be associated with the ability to process fast OF stimulation.     

The Indispensability of Knowledge

Philosophia - Nuno Venturinha holds that the contextualist epistemology adumbrated in Wittgenstein’s On Certainty--the most powerful response to philosophical skepticism yet developed-- falls...     

Toward a social psychophysiology of vagally mediated heart rate variability: Concepts and methods in self‐regulation,emotion, and interpersonal processes

Theory and research on self‐regulation, emotional adjustment, and interpersonal processes focus increasingly on parasympathetic functioning, using measures of vagally mediated heart rate variability (vmHRV) or respiratory sinus arrhythmia (RSA). This review describes models of vmHRV in these areas, and issues in measurement and analysis. We propose a framework organizing theory and research as examining (a) vmHRV as an individual difference or a situational response, and (b) resting, reactive, or recovery levels. Evidence supports interpretation of individual differences in resting vmHRV as a broad biomarker for adaptive functioning, but its specificity and underlying mechanisms require elaboration. Individual differences in vagal reactivity (i.e., trait‐like differences in vmHRV decreases during challenge or stress) are less commonly studied in adults and results are mixed. Many stressors and challenges evoke temporary decreases in vmHRV, and in some research self‐regulatory effort evokes increases. In a smaller literature, positive interpersonal experiences and some restorative processes increase resting vmHRV, whereas depletion of self‐regulatory capacity through related effort decreases it. Greater attention to conceptual distinctions regarding vmHRV constructs and several methodological issues will strengthen future research. Importantly, researchers should exercise caution in equating vmHRV with specific psychosocial constructs, especially in the absence of converging assessments and precise experimental manipulations.     

Relation of maximal ankle dorsiflexion angle and passive resistive torque to passive-elastic stiffness of ankle dorsiflexion stretch

The maximal passive ankle dorsiflexion angle and the maximal passive resistive torque at this angle were measured for 81 women 20 to 84 years of age and correlated with the passive-elastic stiffness (stiffness) of an ankle dorsiflexion stretch. Pearson correlation coefficients and multiple regression analyses were used to examine whether the two clinical measurements could predict ankle stiffness. The maximal passive resistive torque showed a moderate correlation with stiffness in the full stretch range (r = .69) and high correlation with stiffness in the last half of the full stretch range (r = .84). The maximal dorsiflexion angle showed a low correlation with stiffness in the full stretch range (r = .27) and in the last half of the full stretch range (r = .36). The maximal passive resistive torque and the dorsiflexion angle together accounted for 54% of the stiffness variance in the full stretch range and 76% of the stiffness variance in the last half of the full stretch range. Thus, the clinical measurements of the maximal passive dorsiflexion angle and the maximal passive resistive torque were directly and significantly related to the ankle dorsiflexion passive-elastic stiffness and good predictors of stiffness in the last half of the passive ankle dorsiflexion stretch.     

The impact of communal-mastery versus self-mastery on emotional outcomes during stressful conditions: a prospective study of Native American women

Past research has examined the stress resiliency of individuals high in sense of personal-mastery. However, it has been theorized that within more collectivist cultures, a sense of shared efficacy, which we call communal-mastery, may be more central to people's resiliency in the face of challenging life circumstances. We compared the impact of sense of self-mastery (i.e., I am the key to my success) to that of communal-mastery (i.e., I am successful by virtue of my social attachments) in a prospective study among a group of rural 103 Native American women residing on Indian Reservations in Montana. We found that women high in communal-mastery experienced less increase in depressive mood and anger, especially when faced with high stress circumstances, than women who were low in communal-mastery. In addition, the beneficial impact of communal-mastery was found to be more effective than self-mastery for these women.