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The resurgence in antiracist activism and education brought with it the need to better understand what racism is and how it operates in the production of racial injustice. Prevailing theories understand racism as fundamentally structural, essentially cognitive, and requiring political philosophical investigation over moral philosophical investigation. Such theories are useful within limits, but ultimately offer an inaccurate or incomplete view of racism. In what follows, I offer a virtue-based account of racism that begins its genesis story with individuals, yet acknowledges and attends to the reality and severity of institutional and structural racism; is essentially both cognitive and non-cognitive; and, prioritizes moral philosophical investigation. Throughout, I apply my theory of racism to various spheres of human experience and history to demonstrate its ability to accurately and comprehensively capture the relevant entities and phenomena implicated in racism. In improving our understanding of racism, I aim to generate more targeted and comprehensive reform that effectively mitigates racism and promotes human and societal flourishing. [ABSTRACT FROM AUTHOR]

This paper employs a longitudinal perspective to examine continued system use (CSU) by individuals in utilitarian, volitional contexts when alternative systems are present. We focus on two key behavioural antecedents of CSU – habit and continuance intention – and theorise how the relationships between CSU and these antecedents evolve over time. In addition, we hypothesise how the interaction effect of habit and intention on CSU evolves temporally. Our theorising differs from extant literature in two important respects: 1) In contrast to the widespread acceptance of the diminishing effect of continuance intention on CSU in the information systems (IS) literature, we hypothesise that in our context, its impact increases with time; and 2) In contrast to the negative moderation effect of habit on the relationship between intention and CSU proposed in the literature, we posit a positive interaction effect. We collect longitudinal survey data on the use of a higher education IS from students in a European university. Our results suggest that the impact of continuance intention on CSU as well as the interaction effect between habit and intention are increasing over time. We further introduce a methodological innovation – the permutation approach to conduct the multi-group analysis with repeated measures – to the literature. [ABSTRACT FROM AUTHOR]

Volitional assessment of quadriceps muscle endurance is clinically relevant in patients with chronic obstructive pulmonary disease (COPD). However, studies that determine the construct validity of volitional tests by comparing them to non-volitional measures are lacking. Therefore, the aim of the current study is to evaluate the correlation between volitional and non-volitional quadriceps muscle endurance in patients with COPD. Quadriceps muscle endurance was evaluated in twenty-six patients with COPD. A volitional isometric and a volitional isokinetic protocol were performed on a computerised dynamometer to determine the isometric time and isokinetic work fatigue index, respectively. Non-volitional assessment of quadriceps muscle endurance was evaluated using repetitive electrical stimulations to establish the isometric muscle force decline. Sixteen patients (61 ± 8 years, 63% male, FEV1 47 (32–53)%) performed all three quadriceps endurance tests conforming to pre-defined test criteria. Both volitional isometric time and isokinetic work fatigue index did not significantly correlate with non-volitional muscle force decline (both p > 0.05). There was a strong correlation between volitional isometric time and isokinetic work fatigue index (rho = −0.716, p = 0.002). To conclude, this study suggests that volitional measures evaluate partly different aspects of quadriceps muscle endurance compared to non-volitional measures. Accordingly, these outcome measures cannot be used interchangeably. [ABSTRACT FROM AUTHOR]

The Caribbean reef shark, Carcharhinus perezi, is known to rest on the substrate, a behaviour not documented in any of its congeners. We quantified the swimming kinematics of C. perezi in the wild and found that the head yawed at a frequency 15% greater than the tail beat, but that the amplitude of the tail exceeded the head yaw by approximately 80% across the range of velocities measured. We found that C. perezi velocity, head yaw frequency, and tailbeat frequency were all less than its obligate ram ventilating congener C. limbatus. [ABSTRACT FROM AUTHOR]

Impairments in social communication are common among neurodevelopmental disorders. While traditional animal models have advanced our understanding of the physiological and pathological development of social behavior, they do not recapitulate some aspects where social communication is essential, such as biparental care and the ability to form long-lasting social bonds. Prairie voles (Microtus ochrogaster) have emerged as a valuable rodent model in social neuroscience because they naturally display these behaviors. Nonetheless, the role of vocalizations in prairie vole social communication remains unclear. Here, we studied the ontogeny [from postnatal days (P) 8–16] of prairie vole pup ultrasonic vocalizations (USVs), both when isolated and when the mother was present but physically unattainable. In contrast to other similarly sized rodents such as mice, prairie vole pups of all ages produced isolation USVs with a relatively low fundamental frequency between 22 and 50 kHz, often with strong harmonic structure. Males consistently emitted vocalizations with a lower frequency than females. With age, pups vocalized less, and the acoustic features of vocalizations (e.g., duration and bandwidth) became more stereotyped. Manipulating an isolated pup's social environment by introducing its mother significantly increased vocal production at older (P12–16) but not younger ages, when pups were likely unable to hear or see her. Our data provide the first indication of a maturation in social context-dependent vocal emission, which may facilitate more active acoustic communication. These results help lay a foundation for the use of prairie voles as a model organism to probe the role of early life experience in the development of social-vocal communication.

Impairments in social communication are common among neurodevelopmental disorders. While traditional animal models have advanced our understanding of the physiological and pathological development of social behavior, they do not recapitulate some aspects where social communication is essential, such as biparental care and the ability to form long-lasting social bonds. Prairie voles (Microtus ochrogaster) have emerged as a valuable rodent model in social neuroscience because they naturally display these behaviors. Nonetheless, the role of vocalizations in prairie vole social communication remains unclear. Here, we studied the ontogeny [from postnatal days (P) 8–16] of prairie vole pup ultrasonic vocalizations (USVs), both when isolated and when the mother was present but physically unattainable. In contrast to other similarly sized rodents such as mice, prairie vole pups of all ages produced isolation USVs with a relatively low fundamental frequency between 22 and 50 kHz, often with strong harmonic structure. Males consistently emitted vocalizations with a lower frequency than females. With age, pups vocalized less, and the acoustic features of vocalizations (e.g., duration and bandwidth) became more stereotyped. Manipulating an isolated pup's social environment by introducing its mother significantly increased vocal production at older (P12–16) but not younger ages, when pups were likely unable to hear or see her. Our data provide the first indication of a maturation in social context-dependent vocal emission, which may facilitate more active acoustic communication. These results help lay a foundation for the use of prairie voles as a model organism to probe the role of early life experience in the development of social-vocal communication. [ABSTRACT FROM AUTHOR]

Laughter is a ubiquitous social signal. Recent work has highlighted distinctions between spontaneous and volitional laughter, which differ in terms of both production mechanisms and perceptual features. Here, we test listeners' ability to infer group identity from volitional and spontaneous laughter, as well as the perceived positivity of these laughs across cultures. Dutch (n = 273) and Japanese (n = 131) participants listened to decontextualized laughter clips and judged (i) whether the laughing person was from their cultural in-group or an out-group; and (ii) whether they thought the laughter was produced spontaneously or volitionally. They also rated the positivity of each laughter clip. Using frequentist and Bayesian analyses, we show that listeners were able to infer group membership from both spontaneous and volitional laughter, and that performance was equivalent for both types of laughter. Spontaneous laughter was rated as more positive than volitional laughter across the two cultures, and in-group laughs were perceived as more positive than out-group laughs by Dutch but not Japanese listeners. Our results demonstrate that both spontaneous and volitional laughter can be used by listeners to infer laughers' cultural group identity. [ABSTRACT FROM AUTHOR]

Children often show signs of dysregulation, impulsivity, and risk-taking—behaviors that interfere with learning and growth. Commonly implicated in such interfering behaviors are problems of self-control. Several decades of research in the mind and brain sciences inform understanding of self-control, both as a trait and state. This research has significant implications for educators, providing strategies for assessing and strengthening self-control. This paper reviews the relevant theoretical concepts and practical applications. Part one discusses current thinking about the nature of self-control, focusing on the paired distinctions between (i) trait and state, as well as (ii) volitional and impulsive processes. Part two reviews a family of methods designed to assess different aspects of self-control. Part three focuses on ways to strength self-control, including simple strategies that help create habits and reduce conflict with competing temptations.

While evidence suggests that pain cries produced by human babies and other mammal infants communicate pain intensity, whether the pain vocalisations of human adults also encode pain intensity, and which acoustic characteristics influence listeners' perceptions, remains unexplored. Here, we investigated how trained actors communicated pain by comparing the acoustic characteristics of nonverbal vocalisations expressing different levels of pain intensity (mild, moderate and severe). We then performed playback experiments to examine whether vocalisers successfully communicated pain intensity to listeners, and which acoustic characteristics were responsible for variation in pain ratings. We found that the mean and range of voice fundamental frequency (F0, perceived as pitch), the amplitude of the vocalisation, the degree of periodicity of the vocalisation and the proportion of the signal displaying non-linear phenomena all increased with the level of simulated pain intensity. In turn, these parameters predicted increases in listeners' ratings of pain intensity. We also found that while different voice features contributed to increases in pain ratings within each level of expressed pain, a combination of these features explained an impressive amount of the variance in listeners' pain ratings, both across (76%) and within (31–54%) pain levels. Our results show that adult vocalisers can volitionally simulate and modulate pain vocalisations to influence listeners' perceptions of pain in a manner consistent with authentic human infant and nonhuman mammal pain vocalisations, and highlight potential for the development of a practical quantitative tool to improve pain assessment in populations unable to self-report their subjective pain experience. [ABSTRACT FROM AUTHOR]

Copyright of Domínios de Lingu@gem is the property of Dominios de Lingu@gem and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Purpose:To validate outcome variables from the limits of stability protocol that are derived from the center of pressure with those same variables derived from the center of mass during rapid, volitional responses in transtibial prosthesis users. Method:Prosthesis users (n = 21) and matched controls (n = 21) executed movements while force and motion data were collected. Correlation coefficients were used to investigate relationships between center of pressure and center of mass for: x/y coordinates positions, limits of stability outcome variables and muscular reaction times. Results:Significant differences were seen in correlation between x/y coordinate positions toward the intact limb (mean effect size of differences:r = .38). Limits of stability variables were positively correlated (reaction time and maximum excursion rangers: .585–.846; directional control and mean velocity rangers: .307–.472). Muscular reaction times correlated weakly with those from center of pressure (meanrsprosthesis users: .186 and controls: .101). Conclusions:Forceplate measures are valid in describing rapid, volitional movements in unilateral transtibial prosthesis users. Limits of stability outcomes extracted from center of pressure and center of mass are highly correlated, but can be sensitive to direction. Muscular reaction time correlates very little with reaction times extracted from the other variables. Implications for rehabilitationRehabilitation programs utilizing limits of stability are valid measures of postural control in transtibial prosthesis users.Clinicians interpreting the outcomes from limits of stability need to be aware of their varying validity.Muscular reaction times correlate weakly with other measures of reaction time, highlighting the complexity of rapidly coordinating volitional movements in prosthesis users. [ABSTRACT FROM PUBLISHER]

Saccades, rapid movements of the eyes towards a visual or remembered target, are useful in understanding the healthy brain and the pathology of neurological conditions such as progressive supranuclear palsy (PSP). We set out to investigate the parameters of horizontal reflexive and volitional saccades, both visually guided and memory-guided, over a 1 min epoch in healthy individuals and PSP patients. An experimental paradigm tested reflexive, volitional visually guided, and volitional memory-guided saccades in young healthy controls (n = 14; 20–31 years), PSP patients (n = 11; 46–75 years) and older age-matched healthy controls (n = 6; 56–71 years). The accuracy and velocity of saccades was recorded using an EyeBrain T2® video eye tracker and analyses performed using the MyEyeAnalysis® software. Two-way analysis of variance (ANOVA) was used to identify significant effects (p < 0.01) between young and older controls to investigate the effects of ageing upon saccades, and between PSP patients and age-matched controls to study the effects of PSP upon saccades. In both healthy individuals and PSP patients , volitional saccades are slower and less accurate than reflexive saccades. In PSP patients, accuracy is lower across all saccade types compared to age-matched controls, but velocity is lower only for reflexive saccades. Crucially, there is no change in accuracy or velocity of consecutive saccades over short (one-minute) timescales in controls or PSP patients. Velocity and accuracy of saccades in PSP does not decrease over one-minute timescales, contrary to that previously observed in Parkinson's Disease (PD), suggesting a potential clinical biomarker for the distinction of PSP from PD. [ABSTRACT FROM AUTHOR]

Emigration was evaluated for hatchery Chinook salmon (Oncorhynchus tshawytscha) microjacks (age-1 mature males) and immature parr (age-1 juveniles, both sexes) released from both a hatchery and a natural stream (fish released as fry). In the hatchery, volitional releases (∼14 to 15 months post-fertilization) to an adjacent river occurred during October–November. The hatchery release was monitored by using an experimental volitional release that diverted fish to a neighboring raceway. Fish captured during the experimental release (range 361–4,321 volitional migrants) were made up of microjacks and immature parr. Microjacks were found only in the migrant samples, averaged 18% (range 0–52%) of all migrants, and were rarely found in non-migrant samples. In comparison, immature parr were common in both the migrant and non-migrant samples. Microjacks were significantly longer (9%), heavier (36%), and had a greater condition factor (16%) than migrant immature parr (P < 0.01). In addition, they differed significantly (P < 0.01) from non-migrant immature parr; 10% longer, 44% heavier and 14% greater condition factor. In natural streams, microjacks were captured significantly earlier (P < 0.01) than immature parr during the late-summer/fall migration and comprised 9–89% of all fish captured. Microjacks have the potential to contribute to natural spawning populations but can also represent a loss of productivity to hatchery programs or create negative effects by introducing non-native genes to wild populations and should be monitored by fishery managers. [ABSTRACT FROM AUTHOR]

Copyright of Gymnasium: Scientific Journal of Education, Sports & Health is the property of Alma Mater and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: Background: Testosterone has been related to improved acute neuromuscular performance in athletic populations. It is our contention that testosterone may also contribute to improved volitional motivation and, when monitored longitudinally, may provide one proxy marker for readiness to perform. Methods: Twelve female netball players provided saliva samples prior to five standardized training sessions in which they completed a maximal-distance medicine ball throw, and then 3 sets of bench press and then back squat using a self-selected load perceived to equal a 3-repetition maximum load. Additional repetitions were encouraged when possible and total voluntary workload was calculated from the product of the load lifted and repetitions performed. Results: Relative salivary testosterone levels as a group were correlated with bench press (r=0.8399; p=0.0007) and squat (r=0.6703; p=0.0171) self-selected workload, as well as maximal medicine ball throw performance (r=0.7062; p=0.0103). Conclusions: Individual salivary testosterone, when viewed relatively over time, demonstrated strong relationships with self-selected workloads during an in-season training period in female netball players. As such, daily variations in testosterone may provide information regarding voluntary training motivation and readiness to perform in elite athletic populations. Psychological and behavioral aspects of testosterone may have the potential to enhance training adaptation by complementing the known anabolic and permissive properties of testosterone. [Copyright &y& Elsevier]

Saccades made to the opposite side of a visual stimulus (antisaccades) and to central cues (simple volitional saccades) both require active response selection but whether the mechanisms of response selection differ between these tasks is unclear. Response selection can be assessed by increasing the number of response alternatives: this leads to increased reaction times when response selection is more demanding. We compared the reaction times of prosaccades, antisaccades, saccades cued by a central arrow, and saccades cued by a central number, in blocks of either two or six possible responses. In the two-response blocks, reaction times were fastest for prosaccades and antisaccades, and slowest for arrow-cued and number-cued saccades. Increasing response alternatives from two to six caused a paradoxical reduction in reaction times of prosaccades, had no effect on arrow-cued saccades, and led to a large increase in reaction times of number-cued saccades. For antisaccade reaction times, the effect of increasing response alternatives was intermediate, greater than that for arrow-cued saccades but less than that for number-cued saccades. We suggest that this pattern of results may reflect two components of saccadic processing: (a) response triggering, which is more rapid with a peripheral stimulus as in the prosaccade and antisaccade tasks and (b) response selection, which is more demanding for the antisaccade and number-cued saccade tasks, and more automatic when there is direct stimulus-response mapping as with prosaccades, or over-learned symbols as with arrow-cued saccades. [ABSTRACT FROM AUTHOR]

Abstract: Objectives: Point-of-choice prompts consistently increase stair climbing in public access settings. This study investigated the single and combined effects of a volitional and motivational component of a stair climbing intervention to test the theory underlying the success of point-of-choice prompts. Design: Quasi-experimental, interrupted time series cross-over design. Methods: Ascending stair/escalator choices were observed in a UK tram station (n =38,187). Baseline observations (2 weeks; stage 1) preceded a 2-week point-of-choice prompt positioned alone (stage 2) followed by an additional message positioned at the top of each climb (6 weeks; stage 3). Four weeks after message removal, another baseline (2 weeks; stage 4) preceded installation of the intervention components in reverse order. Thus, the message positioned alone at the top of each climb (4 weeks, stage 5) was supplemented with the point-of-choice prompt (2 weeks, stage 6). Logistic regression analyses of stair/escalator choice included the independent variables of intervention components, gender, time of morning and pedestrian traffic volume. Results: There was no change in stair climbing percentages when only one intervention component was used, i.e. only the point-of-choice or the message at the top of each climb. In contrast, stair climbing increased when both components of the intervention were installed. Additionally, men took the stairs more than women and stair climbing was more common earlier in the morning and at higher pedestrian traffic volumes. Conclusions: A motivational component targeting intentions increased the effectiveness of a volitional point-of-choice prompt for stair climbing in a setting where choice of the stairs incurred a time penalty for pedestrians due to the site layout. [Copyright &y& Elsevier]

The aim of this study is to determine how personality disorders (PDs) are viewed in relation to criminal responsibility (CR) within the jurisprudence of the Spanish Supreme Court. All sentences with PD from 2000 to 2006 were included. The most frequently occurring PDs are cluster B and nonspecific disorders, alongside another Axis I disorder. The Spanish Supreme Court admitted appeals on 50%, and sentencing criteria were changed in 25% of the cases. The most frequent outcome was in the first instance a minor reduction in CR and second full CR being upheld. The borderline PD and the comorbidity between a PD and an Axis I disorder are the variables associated with the decrease in CR. The assessment of CR in PD should be undertaken using the diagnosis as a base taking into account other elements, such as the type of PD, its seriousness, comorbidity, and relationship with the criminal behavior on trial. [ABSTRACT FROM AUTHOR]

Abstract: Objective: Inappropriate muscle activity is common following stroke. Paretic muscle activation may be influenced by non-paretic volitional activation. We examined the influence of non-paretic quadriceps activation on paretic quadriceps excitability. Methods: Individuals with chronic stroke performed bilateral and unilateral (paretic and non-paretic) maximum voluntary isometric contractions. Peak torque and muscle activity were compared between conditions. An instrumented tendon tapper elicited a patellar tendon reflex of the relaxed paretic leg while the non-paretic leg was relaxed and pre-activated. The threshold to elicit a paretic quadriceps response was compared between conditions. Results: During the bilateral MVIC, the paretic quadriceps generated less absolute torque, but greater relative torque than the non-paretic side when normalized to the respective unilateral condition (p <0.05). During reflex testing, the tendon tapping threshold to elicit paretic muscle and torque responses decreased with non-paretic activity (p <0.05). Conclusions: Concurrent non-paretic activation resulted in a relative disinhibition of the paretic quadriceps. The paretic limb’s inability to remain inactive during isolated non-paretic contractions implies increased excitation or decreased inhibition of paretic motor pools, although the source remains unknown. Significance: Unwanted muscle activity during reciprocal tasks (gait training) may be due to contralateral effects of non-paretic muscle activity. [ABSTRACT FROM AUTHOR]

Abstract: There is a well-documented disruption of the neural network associated with reward evaluation in schizophrenia. This same system is involved in coding the incentive value of food in healthy individuals, but few studies to date have examined anhedonia and its relation to food hedonicity and preference in schizophrenia. Relative preference and hedonic food ratings were examined in schizophrenia patients and healthy controls. In the relative preference task, subjects viewed photographs of food items and selected the one that they most preferred. Hedonic ratings were obtained by asking subjects how much they liked the food stimulus on a scale of 1–5. There were no overall response time differences between the two groups in the relative preference task, but schizophrenia patients showed subtle differences in their hedonic ratings of foods compared with control subjects. Schizophrenia patients gave more positive hedonic ratings for food than did controls, and the use of fewer positive ratings was associated with increased anhedonia, particularly with loss of sexual interest. These results suggest that while making relative preference judgments may be intact, hedonic values attached to food may be altered in schizophrenia, and they may be related to dysfunction in more basic vegetative systems. [Copyright &y& Elsevier]

Abstract: The purpose of this study was to determine whether stability and limb support play a similar role in governing slip outcome in gait-slip as in sit-to-stand-slip, and whether such prediction could also be derived based on measures of these variables during regular, unperturbed movements. Fifty-three and forty-one young subjects all took one recovery step following an unannounced, novel, forward slip induced in gait and in sit-to-stand, respectively. Logistic regression was used to predict recovery outcome based on preslip and reactive measures of stability and limb support across tasks. Following slip onset, all subjects in both tasks experienced rapid decay in stability and limb support (indicated by a hip descent), leading to some actual falls that could not have been predicted from regular, preslip walking. Immediately before recovery step touchdown, stability and limb support could together best predict 88.9% and 100% falls, respectively, for gait-slip and sit-to-stand-slip. Because of differences in the execution of the recovery step, stability became a better predictor of fallers in sit-to-stand-slip than in gait-slip after recovery limb touchdown. Recovery steps were highly effective in restoring stability, regardless of outcome and task. The predictive strength of stability diminished in gait-slip or reduced in sit-to-stand-slip after recovery touchdown, while limb support remained able to differentiate fallers from those who recovered in both tasks. When slip-induced instability was combined with inadequate limb support, falls were nearly inevitable in both tasks. [Copyright &y& Elsevier]

Objective: This research sought to identify a well-defined pre-motor potential, the Bereitschaftspotential (BP), as a manifestation of cortical contribution to the pre-motor planning of volitional swallowing. Methods: EEC data were collected from 20 research participants during volitional execution of swallowing and finger movement tasks. AS second pre-movement epoch for each task was triggered on EMG identification of movement onset. A grand average for each task representing approximately 2400 trials across all research participants was derived to compare and contrast morphological features of the derived waveform. Results: Volitional pharyngeal swallowing and finger movement generated similar waveform characteristics of duration and slope; however, statistically significant differences were identified in polarity and in amplitude at four points both early and late in the epoch. Additionally, swallowing produced a pre-motor waveform with a rapid declination of EEG activity in the final 500 msec prior to movement onset. Conclusions: This study demonstrates activation of the supplementary motor cortex preceding the onset of volitional swallowing. However, unlike purely voluntary movements, the volitional pharyngeal swallowing task, as assessed with this methodology, does not appear to recruit the primary motor cortex. Thus engagement of the swallowing response appears to rely on indirect parallel pathways between extrapyramidal cortical motor planning regions and lower motor neurons. [ABSTRACT FROM AUTHOR]