The effects of lemon taste on attention,perceived exertion,and affect during a stepping task

ObjectivesTo better understand the effects of taste cues on delaying the attention shift from an external focus (dissociative) towards an internal focus (associative) as exercise intensity increases.DesignA between subjects' experimental design with random assignment to three groups: taste (lemon-flavored mouth guards), placebo (unflavored mouth guards), or control group (no mouth guards) was used. Participants reported perceived exertion, affect (i.e., pleasantness and arousal), and attention allocation before, during, and after performing a weighted stepping task.ResultsPerforming the task resulted in a gradual increase of perceived exertion, F (1.87, 74.89) = 63.05, p < .05, η_p² = .61, along with a shift from dissociative to associative attention, F (2.17, 86.68) = 35.57, p < .05, η_p² = .47 across all conditions. Additionally, participants reported feeling less pleasant and more aroused after task completion in all conditions. The lemon-flavored mouth guard failed to affect attention, F (4.33, 86.68) = 1.41, p = .23, η_p² = .07, perceived exertion, F (3.74, 74.86) = .38, p = .81, η_p² = .02, pleasantness, F (2, 40) = .126, p = .88, η_p² = .01, and arousal, F (2, 40) = 2.40, p = .10, η_p² = .10, differently than the other two conditions.ConclusionsThe study was one of the first to examine the effects of taste during an exertive task. Despite the non-significant effects of using a lemon-taste mouth guard on various cognitive variables (perception of exertion, attention allocation, pleasantness, and arousal), more scientific effort is needed to explore the effects of other tastes (e.g., sweet, bitter) and delivery methods (e.g., sprays, drops).     

Attitude,perceived behavioral control,and intention to adopt risky behaviors

The theory of planned behavior (TPB, Ajzen, 1985) has proved its efficiency in predicting different behaviors among road users (Sheeran & Orbell, 2000). The present study examined the TPB factors explaining risk taking among vulnerable road users (e.g., cyclists). We presumed that attitude, social norms, and perceived behavioral control (PBC) would predict cyclists’ intention to adopt a risky behavior in two traffic contexts considered as risk-conducive (i.e., run the red-light, turn left).Participants (N = 224, M_age = 23.34) filled in an online scenario-based questionnaire describing two traffic situations conducive to risk taking and including measures for cyclists’ intentions to adopt risky behaviors in these specific contexts, TPB factors, and self-perceived efficacy.TPB factors explained 49% and 65% of the variance in the intention to cross the red light, respectively the intention to turn left, with positive attitude and high PBC as the best predictors. Implications of the results were discussed.     

Cyclists’ handheld phone use and traffic rule knowledge

Phone use is likely to distract cyclists and possibly increase crash risk. Therefore, handheld phone use among cyclists is forbidden by law in some countries, even though cyclists use compensatory strategies to attempt to mitigate distractions and related effects. Both demographic, environmental, and psychological factors have been associated with cyclists’ phone use. This study extends the existing literature by including traffic rule beliefs as an explanatory measure in predicting cyclists’ handheld phone use and additionally explores how well cyclists know these rules in different legislative contexts. Online questionnaire responses were collected in 2019 among 1055 cyclists living in Denmark (N = 568), where handheld phone use for cyclists was forbidden, and in the Netherlands (N = 487), where it was legal. Responses on phone use, traffic rule knowledge, cycling behaviour, demographic, and psychological measures were used to identify factors contributing to the likelihood of handheld phone use in three regression models; one for all respondents and one for each country. In the combined model, believing there are no rules on handheld phone use increased the likelihood of handheld phone use while cycling. Other significant factors were subjective norm, perceived behavioural difficulty, self-identity as a safe cyclist as well as demographic factors. The country-specific models found that male gender was only associated with more handheld phone use in the Netherlands, while believing there was no ban was only connected to an increase in the likelihood of using handheld phone in Denmark. Correct traffic rule knowledge was almost three times higher in Denmark, where handheld phone use was forbidden. The results identify subjective norms, potential overconfidence, and traffic rule awareness (when there is a ban) as relevant factors in reducing the likelihood of cyclists’ handheld phone use. Findings from country-specific models possibly point to a connection between culture and traffic rules. Future research should focus on underlying mechanisms and awareness of traffic rules.     

The perception of bicycle crashes with and without motor vehicles: Which crash types do older and middle-aged cyclists fear most?

Several studies have focused on the perceived risk of bicycle crashes (irrespective of crash types) and concluded that cycling near high volumes of motor vehicles deters people from cycling. The perceived risk of bicycle crash types (with or without motor vehicles) has not yet been studied. Cyclists, both in countries with low and high levels of cycling participation, are substantially more likely to sustain severe injuries in single-bicycle crashes than in bicycle-motor vehicle crashes. This questionnaire study sets out to compare which bicycle crash types are perceived to cause most hospitalizations among cyclists. The study comprised cyclists over 55 years in the Netherlands, and over 40 years in the Belgian regions of Flanders (a region with high cycling participation), Brussels and Wallonia (regions with low cycling participation). The majority of cyclists (60%) perceive bicycle-motor vehicle crashes cause most hospitalizations among cyclists. This percentage is greatest in the areas of Brussels and Wallonia and lowest in the Netherlands. Cyclists who were involved in a bicycle-motor vehicle crash themselves are more likely to regard this crash type as the most common cause of hospitalizations among cyclists, while cyclists over 60 years who were involved in a crash without a motor vehicle are more likely to perceive that crash type as the most common cause. The smaller perception bias in the study areas with higher cycling participation – particularly the Netherlands and to a somewhat lesser degree Flanders – is probably due to bicycle infrastructure being more separated from high-speed motor traffic, leaving cyclists less exposed. The outcomes show that cyclists underestimate the likelihood of severe injuries due to single-bicycle crashes. New interventions should raise the awareness of the risk of single-bicycle crashes and provide solutions to avoid such crashes.     

Perceptions of inferred parental ability through sexually dimorphic facial features

In addition to providing robust cues diagnostic of prospective mates' heritable fitness, various physical features could be similarly utilized in inferring individuals' parental abilities. This study sought to explore how variations in sexually dimorphic facial features inform perceptions of social targets as motivated to provide parental care. American undergraduates (N = 244) viewed a series of 12 total male and female faces manipulated at varying degrees of sex-typicality (i.e., masculinized versus feminized versus unaltered controls) on a within-subjects basis, and rated the perceived motivation of each target to nurture and protect a child using items derived from the Parental Care and Tenderness Scale. Female targets were perceived as more motivated by parental care than male targets, F(1, 240) = 14.86, p < .001, η_p² = 0.058, whereas male targets were perceived as specifically motivated to protect offspring, F(1, 240) = 177.32, p < .001, η_p² = 0.425. Feminized targets were additionally perceived as more motivated by nurturance, though such inferences were apparent for both male and female targets, F(1, 240) = 7.36, p < .001, η_p² = 0.058. Findings represent an understanding of perceivers use of functional heuristics of sexual dimorphism in identifying optimal parents.     

A gender role socialization model of explicit and implicit biases in driving self-enhancement

We present a gender role socialization model of explicit and implicit biases in driving self-enhancement. The model proposes that men’s higher levels of driving self-enhancement (relative to women) results from socialization experiences, such as those that idealize driving skill and risk taking as core aspects of male identity. This socialization process produces reasoned explicit (declarative or propositional) associations, but also implicit (automatic, non-conscious) associations between masculinity and driving self-enhancement, and these two processes are theorized to operate relatively independently. Structural Equation Modeling of a large sample of young male (n = 200) and female (n = 200) drivers supported the model, and indicated that (a) gender role identification fully mediated the effect of gender on driving self-enhancement and (b) that this effect occurred simultaneously but relatively independently in both explicit or reasoned belief structures and also in implicit non-conscious associations assessed using the Implicit Association Test. The origins of gender differences in traffic safety behaviour and the implications of our model for shifting conceptions of what it means to be a “real man” with regard to driver behaviour are discussed.     

Why people fail to bike the talk: Car dependence as a barrier to cycling

Antecedent conditions of cycling have been extensively studied, yet barriers that prevent individuals from choosing bicycle transportation are less known. The present study, conducted on a sample of individuals who were both cyclists and drivers (N = 280), investigated whether dependence on car transportation significantly reduces cycling frequency. It also assessed the predictive validity of a larger set of cycling determinants that included moral, objective environmental, demographic and car-related variables. Responses were analyzed using a structural equation modeling approach. Results show that moral considerations do little to predict cycling frequency and that car-related factors such as perceived behavioral control to reduce car use (β = 0.28) and car use habits (β = -0.27) have the strongest predictive power. Objective environmental factors such as temperature (β = -0.13) and altitude (β = -0.15) or demographic factors such as gender (β = 0.19) were also significant predictors of cycling frequency. The present study highlights a new perspective of understanding cycling behavior and pleads for the inclusion of car-related factors in its future conceptualizations and interventions to encourage it.     

Associations between peer victimization,perceived teacher unfairness,and adolescents' adjustment and well-being

Negative relationships within the classroom, both with peers and teachers, can be very stressful for adolescents and are often found to be associated with a variety of negative outcomes. In this study, we investigated the concurrent role of peer victimization and perceived teacher unfairness in explaining psychosocial problems in a sample of 1378 Italian students (353 middle school students, M_age = 12.61, SD = 0.69, and 1025 high school students, M_age = 14.92, SD = 0.81). Structural equation modeling showed that both peer victimization and perceived teacher unfairness were positively associated with reports of more frequent psychological and somatic problems, and negatively related to satisfaction with friends and sense of safety. Only perceived teacher unfairness showed a significant association with satisfaction with school. Results of multi-group modeling demonstrated measurement invariance (total scalar invariance) across both gender and school-level groups. Some gender and school-level differences in the regression coefficients were found. In general, associations between the risk factors and adolescents' problems were stronger for girls and for higher school students. Findings confirmed that both peer victimization and perceived teacher unfairness are significant risk factors within the classroom microsystems. Implications for school psychologists are discussed.     

Risk comparative judgments while driving a car among competitive road cyclists and non-cyclists

This study examines risk comparative judgments and risky behaviors while driving a car among competitive road cyclists (n = 119) and among controls (i.e., drivers who have almost no cycling experience, n = 142). A questionnaire-based cross-sectional survey was conducted. Results showed that competitive road cyclists assess their own vulnerability to be involved in an accident while riding (VAR) as being lower than that of the average cyclists, and their abilities to manage risks while riding (AMRR) as being higher. They assessed their own vulnerability to be involved in an accident while driving a car (VAD) as being lower than that of the average drivers, and their own quality of reflexes while driving a car (QRD) as being higher. Their tendency to express comparative optimism while assessing their comparative VAD and QRD was higher than that of controls. They also reported more prudent behaviors while driving a car than did controls. Results are discussed, as well as implications in terms of prevention.     

Sex differences in the impact of state and trait fatigue on gait variability

Conditions requiring greater attention or cognitive control, such as fatigue, lead to changes in the motor performance of a task. Perceived fatigue refers to subjective feelings of fatigue, can be expressed as a state variable or trait characteristic and is influenced by demographic factors, such as sex. The purpose of this study was to determine how sex interacts with state and trait physical fatigue (PF) and mental fatigue (MF) to influence gait variability. METHODS: 123 healthy adults (77 female, 46 male), aged 18–36 years, completed the Mental and Physical State and Trait Energy and Fatigue Scale. Using a median split for each fatigue variable, participants were placed into “low” or “high” fatigue categories. Gait variability was defined as the asymmetry of lateral step variability (ALSV) and coefficient of variation (CV) of gait speed, stride length and double limb (DL) support during overground walking. RESULTS: Males with low state PF had greater ALSV than females with low state PF (p = 0.05, η²_p = 0.07) and males with high state PF (p = 0.007, η²_p = 0.15). Females with high trait MF had greater CV of gait speed than females with low trait mental fatigue (p = 0.02, η²_p = 0.08). Males with low trait MF had greater CV of gait speed (p = 0.01, η²_p = 0.10) and stride length (p = 0.002, η²_p = 0.17) than females with low trait MF. CV of DL support did not vary based on fatigue level or sex (p ≥ 0.11). CONCLUSIONS: There are sex-specific differences in the impact of state PF on asymmetry of lateral step variability and trait MF on the variability of gait speed and stride length.     

Psychometric properties of driver self-image inventory for Chinese drivers and its associations with personality and driving style

This study aimed to adapt the Driver Self-image Inventory (DSII, Taubman-Ben-Ari, 2008) to Chinese drivers and examine its relationship with personality traits and driving style. Six hundred forty drivers aged 18–55 years agreed to participate in this study. Measurements included the DSII, a personality scale and a validated Chinese version of the Multidimensional Driving Style Inventory (MDSI). The results of exploratory factor analysis (n = 302) and confirmatory factor analysis (n = 305) yielded a three-factor scale with satisfactory reliability. Significant gender differences were found on the DSII factors, with male drivers scoring higher on the impulsive driver factor and lower on the cautious driver factor than female drivers. The validity of the DSII was supported by significant associations between the DSII factors and personality traits, driving style and number of traffic violations and accidents in the previous 12 months. Moreover, drivers with traffic accidents scored significantly lower on the cautious driver factor and higher on the impulsive driver factor than those without traffic accidents. These findings indicate that the reliability and validity of the Chinese version of the DSII are acceptable.     

Perceptions of traffic risk in an industrialised and a developing country

This study aimed to investigate differences in traffic risk perception among a Norwegian and Ghanaian public. This was carried out while controlling for relevant background variables such as gender, age, and levels of educational achievement. In order to obtain the core aim of the study, a self-completion questionnaire was devised and distributed to a representative sample of the Norwegian population (n = 247) and to a stratified sample in Accra and Cape-Coast in Ghana (n = 299). The results showed that the Ghanaian sample perceived higher traffic risk than the Norwegian sample. Gender, age, and levels of educational achievement exerted minimal influences on risk perception. The results were discussed in context of industrialisation, cultural differences, and health beliefs.     

Effect of psychostimulant medications on static balance performance in adults with attention deficit hyperactivity disorder: Within-subjects repeated-measure study

ObjectiveThis study examined the effect of psychostimulant medications nPS) on balance and functional motor performance in adults with attention-deficit/hyperactivity disorder (ADHD).MethodsParticipants completed two sessions (off-medication and on-medication) in a within-subjects repeated-measure study design. There was a minimum of seven days between the two sessions. During both sessions, participants stood for 30 s per condition on a force platform. The conditions were: feet-apart with 1) eyes-open and 2) eyes-closed; feet-together with 3) eyes-open and 4) eyes-closed. Participants performed three trials of timed up and go (TUG) and lateral step-up test (LSUT) during both sessions. Outcome measures were sway area (SA [cm²]), average sway velocity (SV [cm/s]), TUG average time (s), and average number of LSUT repetitions. Data were analyzed using multivariate repeated measures analysis of variance and paired t-tests for examining PS effects on balance (SA and SV) and functional motor performance (TUG and LSUT), respectively.ResultsThe sample included 45 adults (35 females; mean age = 28.4 ± 6.3 years). The repeated-measures MANOVA indicated that PS was associated with better SA [F(1,44) = 9.6; p = 0.003;η_p² = 0.18] but not with SV [F(1,44) = 1.0; p = 0.319;η_p² = 0.02]. PS was associated with significantly better SA with decreasing base-of-support [F(1,44) = 9.9; p = 0.003;η_p² = 0.18]. Additionally, PS use was associated with better TUG [t(1,44) = 2.65; p = 0.014;Cohen's d = 0.39] but not LSUT performances [t(1,44) = −0.68; p = 0.499;Cohen's d = −0.10].ConclusionsPS was associated with better SA and TUG in adults with ADHD. Further studies are needed to investigate the effects of PS on balance performance using rigorous designs in this population.ImpactHealthcare providers should screen for PS status and balance when treating adults with ADHD to enhance safe motor performance.     

Socio-economic and driving experience factors affecting drivers’ perceptions of traffic crash risk

Drivers are estimated to contribute an overwhelming proportion to the burden of traffic crashes, as factors that increase crash risk are frequently due to unsafe driving behaviours. The relationship between risk perceptions and people’s risky driving behaviours is still not well understood. This paper aims to further analyse the potential effect of risky driving behaviours on drivers’ perceptions of crash risk and differences in perceptions among drivers.Crash risk perceptions in an inter-city, two-way road context of 492 drivers were measured by using a Stated Preference (SP) ranking survey. Rank-ordered logit models were used to evaluate the impact on risk perception of five unsafe driving behaviours and to identify differences in drivers’ risk perceptions. The five unsafe driving behaviours considered in the analysis were respectively related to whether or not the driver follows the speed limits, the rules of passing another car and the safe distance, whether or not the driver is distracted, and whether or not she/he is driving under optimal personal conditions.All risky driving behaviours showed a significant potential effect (p < 0.001) on crash risk perceptions, and model’s results allowed to differentiate more important from less important unsafe driving behaviours based on their weight on perceived crash risk. Additionally, this paper further analyses the potential differences in risk perception of these traffic violations between drivers of different characteristics, such as driving experience, household size, income and gender.The SP technique could be applied to further analyse differences in perceptions of risky driving behaviours among drivers. Future research should consider the potential effect of driving skill on perceptions of risky driving behaviours.     

Personality and demographic differences in the perceived risks of potentially timid driving behaviours

Timid driving behaviours can be described as overly cautious and hesitant driving behaviours. Little research has examined behaviours that potentially resemble timid driving and how these behaviours are perceived by other drivers. This is despite the potential for these behaviours to be perceived in a way that leads to angry and aggressive retaliatory behaviours in some drivers (e.g., in anger-prone drivers). We conducted an online survey examining the perceived road safety risks of several behaviours that could potentially result from timid driving and their relationships with driver personality (trait anxiety, trait driving anger), behaviour (anxious driving, angry driving), and demographic (age, gender, annual mileage) background. Drivers (N = 439, M_age = 49.41 ± 5.59 years, aged 18–89) perceived excessively cautious and unpredictable braking behaviours as posing moderate levels of risk. Multiple linear regression analyses also indicated higher perceived risks of slow and excessively cautious behaviours in older, male, and anger prone drivers. No meaningful associations were found between driver characteristics and the risks of unpredictable braking behaviours. These results suggest that safety campaigns to reduce aggressive behaviour may benefit from targeting the perceptions of other drivers’ behaviours.     

Manual drivers’ experience and driving behavior in repeated interactions with automated Level 3 vehicles in mixed traffic on the highway

In the near future, conditionally automated vehicles (CAVs; SAE Level 3) will travel alongside manual drivers (≤ SAE level 2) in mixed traffic on the highway. It is yet unclear how manual drivers will react to these vehicles beyond first contact when they interact repeatedly with multiple CAVs on longer highway sections or even during entire highway trips. In a driving simulator study, we investigated the subjective experience and behavioral reactions of N = 51 manual drivers aged 22 to 74 years (M = 41.5 years, SD = 18.1, 22 female) to driving in mixed traffic in repeated interactions with first-generation Level 3 vehicles on four highway sections (each 35 km long), each of which included three typical speed limits (80 km/h, 100 km/h, 130 km/h) on German highways. Moreover, the highway sections differed regarding the penetration rate of CAVs in mixed traffic (within-subjects factor; 0%, 25%, 50%, 75%). The drivers were assigned to one of three experimental groups, in which the CAVs differed regarding their external marking, (1) status eHMI, (2) no eHMI, and (3) a control group without information about the mixed traffic. After each highway section, drivers rated perceived safety, comfort, and perceived efficiency. Drivers were also asked to estimate the penetration rate of CAVs on the previous highway section. In addition, we analyzed drivers’ average speed and their minimum time headways to lead vehicles for each speed zone (80 km/h, 100 km/h, 130 km/h) as well as the percentage of safety critical interactions with lead vehicles (< 1 s time headway). Results showed that manual drivers experienced driving in mixed traffic, on average, as more uncomfortable, less safe and less efficient than driving in manual traffic, but not as dangerous. A status eHMI helps manual drivers identify CAVs in mixed traffic, but the eHMI had no effect on manual drivers’ subjective ratings or driving behavior. Starting at a level of 25% Level 3 vehicles in mixed traffic, participants' average speed decreased significantly. At the same time, the percentage of safety critical interactions with lead vehicles increased with an increasing penetration rate of CAVs. Accordingly, additional measures may be necessary in order to at least keep the existing safety level of driving on the highway.     

Psychosocial determinants of road traffic offences in a sample of Spanish male prison inmates

ObjectiveThere is very little information available about the characteristics of drivers convicted for traffic offences. The objective of this study was to perform a comparative analysis of the psychosocial characteristics of Spanish prison inmates convicted of road traffic offences (CRTOs), drivers serving a prison sentence for other types of offence (DCOOs), and drivers with no criminal record (DNCRs), in order to identify the psychosocial predictors associated with RTOs.MethodsThe study sample comprised 434 male participants divided into three groups: CRTO (n = 240); DCOO (n = 85); and DNCR (n = 105). Instruments included an interview on sociodemographic data, driving behaviour, and past offences, as well as a set of tests to evaluate personality traits (ZKPQ-50CC), driving-related aspects (MDSI-S and DAS), and alcohol dependence (AUDIT).ResultsA logistic regression analysis showed the following to be reliable predictors of RTOs: low education level (p < .05); having been involved in several road traffic accidents (p < .001); having received several fines (p < .001); a high score on the MDSI-S Risky subscale (p < .05); a low score on the MDSI-S Careful subscale (p < .05); AUDIT scores > 8 (p < .05), and repeatedly driving whilst under the influence of alcohol (p < .05).ConclusionsThe results obtained have significant practical implications for designing and implementing traffic offenders programmes.     

Refreshing Older Adults’ Driving Skills (ROADSkills): A randomized controlled trial examining the effect of video feedback

ObjectivesThis study evaluated the effectiveness of a personalized video-based driver training program on the behind-the-wheel skills of community-dwelling older adults.MethodIn this randomized controlled trial (RCT), 80 older drivers [mean age (SD) = 71.0 (3.9)] were randomly assigned to view one of two educational videos: 1) personalized video feedback on their driving (n = 40) or 2) a generic video on aging-in-place (n = 40). The primary outcome, the total number of errors accrued in a 30-minute standardized on-road evaluation, was analyzed at baseline and 4 weeks after watching the assigned video. On-road evaluations were video-recorded and scored by a blinded rater. Self-report measures of driving abilities, behaviors, and comfort were also compared.ResultsAt the 4-week follow-up, the mean difference in the number of on-road performance errors [mean (95% CI) = -12.0 (-16.6, −7.4), p < 0.001] favored the intervention group compared to controls, with significant improvements across multiple domains: vehicle control [mean (95% CI) = -4.8 (-8.1, −1.5), p < 0.01], observing the roadway [mean (95% CI) = -5.5 (-8.4, −2.6), p < 0.001], and compliance with traffic rules [mean (95% CI) = -1.3 (-2.3, −0.2), p < 0.05]. Within-group change on behind-the-wheel errors was significant for the intervention group [mean (95% CI) = -10.3 (-13.5, −7.1), p < 0.001], but not for the control group [mean (95% CI) = 1.7 (-1.6, 4.9), p > 0.05]. No significant differences were found on the self-report measures.DiscussionA novel, video-based approach that provided personalized feedback to older drivers significantly reduced behind-the-wheel errors 4-weeks post-intervention. Changes in self-reported driving behaviors and abilities were not significant. Future research will examine the long-term effects of this approach on older adults’ actual and perceived driving abilities.     

Shared road is double happiness: Evaluation of a “Share the road” sign

A road sign with the text «Share the road» and a picture of a smiling cyclist and a passing car was evaluated in a before–after study with surveys among cyclists and car drivers. The sign was set up at two sites on a test road near Oslo in summer 2014. A similar road was used as a comparison. About two thirds of the participants on the test road had noticed the sign. The majority liked it and agreed with its message. Cyclists have more often noticed the sign than car drivers have and they were somewhat more positive towards the sign. Effects on self-reported behavior and the perceived behavior of others were evaluated by comparing changes from the before- to the after-period between test and comparison road. Self-reported behavior of both cyclists and car drivers has improved on the test road after the sign was set up, especially in overtaking situations, and these results are in accordance with how cyclists and car drivers perceived each other’s behavior. The general perception of other road users has improved as well. The results are most likely representative of similar roads with a large proportion of car traffic that is related to recreation and a relatively low level of conflict.