A comparison of experienced and novice drivers’ rear-end collision avoidance maneuvers under urgent decelerating events

A leading vehicle’s sudden deceleration can lead to a rear-end collision. Due to a lack of driving experience, novice drivers have a greater tendency to be involved in these accidents. Most previous studies have examined driver response time and braking behaviors, but few researchers have focused on what experienced and novice drivers did after their feet touched the braking pedal and their hands turned the steering wheel. These braking and steering parameters are essential in understanding driver avoidance behavior during emergencies. We programmed rear-end crash risk scenarios to examine experienced and novice drivers’ behaviors thoroughly using a driving simulator. Twenty experienced and twenty five novice subjects participated in our experiments, and their braking and steering maneuvers were recorded when leading vehicles ran at 60 km/h, 80 km/h and 100 km/h. The results showed that the two groups of subjects tended to execute two kinds of maneuvers to avoid crashes: braking only (novice 33%, experienced 19%) and the combination of braking with steering (novice 22%, experienced 26%). When the novice drivers executed braking with steering, their response time and steering duration were significantly longer than those of the experienced drivers who executed braking with steering. As the speed increased, the novice drivers’ response time, maximum braking force and maximum steering angle were significantly affected. These results showed that novice drivers should brake only when the leading vehicle suddenly decelerates. The experienced drivers executed steadier maneuvers. Their risk perception time was shorter, and their maximum braking force and the maximum steering angles were smaller. The response time, braking intensity and steering wheel angle should be considered when developing rear-end collision warning systems.     

Coordination tending towards an anti-phase relationship determines greater sway reduction during entrainment with a simulated partner

The increased risk of falls in the older aged population demands the development of assistive robotic devices capable of effective balance support. For the development and increased user acceptance of such devices, which provide balance support in a human-like way, it is important to understand the simultaneous occurrence of entrainment and sway reduction in human-human interaction. However, sway reduction has not been observed yet during a human touching an external, continuously moving reference, which rather increased human body sway. Therefore, we investigated in 15 healthy young adults (27.20±3.55 years, 6 females) how different simulated sway-responsive interaction partners with different coupling modes affect sway entrainment, sway reduction and relative interpersonal coordination, as well as how these human behaviours differ depending on the individual body schema accuracy. For this, participants were lightly touching a haptic device that either played back an average pre-recorded sway trajectory (“Playback”) or moved based on the sway trajectory simulated by a single-inverted pendulum model with either a positive (Attractor) or negative (Repulsor) coupling to participant's body sway. We found that body sway reduced not only during the Repulsor-interaction, but also during the Playback-interaction. These interactions also showed a relative interpersonal coordination tending more towards an anti-phase relationship, especially the Repulsor. Moreover, the Repulsor led to the strongest sway entrainment. Finally, a better body schema contributed to a reduced body sway in both the “reliable” Repulsor and the “less reliable” Attractor mode. Consequently, a relative interpersonal coordination tending more towards an anti-phase relationship and an accurate body schema are important to facilitate sway reduction.     

Infant recall memory and communication predicts later cognitive development

This longitudinal study investigates the relation between recall memory and communication in infancy and later cognitive development. Twenty-six typically developing Swedish children were tested during infancy for deferred imitation (memory), joint attention (JA), and requesting (nonverbal communication); they also were tested during childhood for language and cognitive competence. Results showed that infants with low performance on both deferred imitation at 9 months and joint attention at 14 months obtained a significantly lower score on a test of cognitive abilities at 4 years of age. This long-term prediction from preverbal infancy to childhood cognition is of interest both to developmental theory and to practice.     

Chimpanzees’ (Pan troglodytes) use of gaze cues in object-choice tasks: different methods yield different results

To assess the influence of different procedures on chimpanzees' performance in object-choice tasks, five adult chimpanzees were tested using three experimenter-given cues to food location: gazing, glancing, and pointing. These cues were delivered to the subjects in an identical fashion but were deployed within the context of two distinct meta-procedures that have been previously employed with this species with conflicting results. In one procedure, the subjects entered the test unit and approached the experimenter (who had already established the cue) on each trial. In the other procedure, the subjects stayed in the test unit throughout a session, witnessed the hiding procedure, and waited for a delay of 10 s during which the cue was provided. The subjects scored at high levels far exceeding chance in response to the gaze cue only when they approached the experimenter for each trial. They performed at chance levels when they stayed inside the test unit throughout the session. They scored at chance levels on all other cues irrespective of the procedure. These findings imply that (a) chimpanzees can immediately exploit social gaze cues, and (b) previous conflicting findings were likely due to the different meta-procedures that were used.     

自我和物体为参照系的心理旋转分离：内旋效应

采用虚拟的旋转不同角度左、右手模型,构建“左右手判断(Left and right hand judgment: LR)”任务和“相同－不同判断(same and different judgment: SD)”任务,考察这两种实验任务是否都存在内旋效应和角度效应,以此推论被试采用何种旋转策略。结果发现：（1） 两种实验任务结果均表现出显著的角度效应。（2）在LR任务条件下,存在显著的内旋效应,而在SD任务中不存在内旋效应。从而表明当人手图片作为心理旋转材料时,它具有双重角色。被试心理旋转加工时究竟选用何种参照系的旋转策略,与实验材料和实验任务两者都密不可分     

Evidence for an antagonistic interaction between reward and punishment sensitivity on striatal activity: A verification of the Joint Subsystems Hypothesis

The Reinforcement Sensitivity Theory proposes that the Behavioral Approach System (BAS) comprises dopaminergic brain regions and underpins reward sensitivity causing impulsivity. It has been shown in a supraliminal priming task that highly reward sensitive subjects have a larger reaction time (RT) priming effect and make more commission errors to prime-incongruent targets. We adapted a similar task to event-related fMRI and hypothesized that (1) high reward sensitivity is associated with increased activation in dopaminergic brain regions, the ventral striatum in particular, (2) that BAS related personality traits predict impulsivity and (3) that the BAS effects are larger after adjusting for the interactive influence of trait avoidance, as predicted by the Joint Subsystems Hypothesis. Fourteen healthy females participated in the fMRI experiment and were scored on sensitivity to reward (SR) and trait avoidance, i.e., sensitivity to punishment (SP) and neuroticism (N). SR scores were adjusted by SP and N scores. As hypothesized, adjusted SR scores predicted, more than SR scores alone, activity in the ventral striatum (left caudate nucleus and nucleus accumbens). SR+/ SP− scores predicted increased impulsiveness, i.e., a right side RT priming effect. These results support the Joint Subsystems Hypothesis.     

Identifying when children with visual impairment share attention: A novel protocol and the impact of visual acuity

BackgroundIn Coordinated Joint Engagement (CJE), children acknowledge that they and their social partners are paying attention to the same object. The achievement of CJE, critical for healthy development, is at risk in infants with visual impairment (VI). Research on CJE in these children is limited because investigators use a child’s gaze switch between social partner and object to index CJE. Research is needed that identifies CJE in children with VI using behaviors that do not require normal vision and that explores the relationship between CJE and visual function. This study aimed to (a) develop a protocol for identifying CJE in children with VI, and (b) explore the relationship between CJE and infants’ visual acuity (VA) and contrast sensitivity (CS), measured with Preferential Looking (PL) techniques and Visual Evoked Potential (VEP).MethodsA protocol that included 9 indices of CJE that did not require normal vision was developed to code videos of 20 infants with VI (mean age =1 year, 6 months, 27 days) and their caregivers. The percentage of CJE episodes in which each index was observed was calculated. Inter-coder reliability was measured using Cohen’s Kappa. Linear regression analysis was used to examine the relationship between the infants’ visual function and CJE.ResultsInter-rater reliability between a first coder and each of two second coders were 0.98 and 0.90 for determining whether the child participated in CJE. The following indices were observed the most (in 43–62 % of CJE): child’s body orientation to caregiver, gaze switch between caregiver and object, and vocalization to caregiver. The only significant model included VA (measured with PL) as a single predictor and explained 26.8 % of the variance in CJE.ConclusionsThe novel protocol can be used to identify CJE in children with VI with good inter-coder reliability. The data suggest that children with lower VA exhibited less CJE.     

The sense of agency in human-human vs human-robot joint action

Kinesthesis pertains to the perception of moving body parts, while the sense of agency refers to the experience of controlling one’s action-effects. Based on previous work, we hypothesized that the sense of agency would decrease in joint action with a robot compared to a human partner. Pairs of participants were jointly manipulating two interconnected haptic devices enabling them to feel each other’s forces. Unbeknown to participants, their partner was sometimes replaced by a robot. The sense of agency was assessed using intentional binding, which refers to a contraction of perceived time between an action and its effect for intentional actions, and participants’ judgment of their contribution to joint action. Participants judged their contribution as higher when they were initiating action and when they were paired with the robot. By contrast, intentional binding occurred only with a human partner. This outcome supports the hypothesis that human-robot joint action hinders intentional binding.     

Exercises focusing on rotator cuff and scapular muscles do not improve shoulder joint position sense in healthy subjects

Proprioception is essential for shoulder neuromuscular control and shoulder stability. Exercise of the rotator cuff and scapulothoracic muscles is an important part of shoulder rehabilitation. The purpose of this study was to investigate the effect of rotator cuff and scapulothoracic muscle exercises on shoulder joint position sense. Thirty-six healthy subjects were recruited and randomly assigned into either a control or training group. The subjects in the training group received closed-chain and open-chain exercises focusing on rotator cuff and scapulothoracic muscles for four weeks. Shoulder joint position sense errors in elevation, including the humerothoracic, glenohumeral and scapulothoracic joints, was measured. After four weeks of exercise training, strength increased overall in the training group, which demonstrated the effect of exercise on the muscular system. However, the changes in shoulder joint position sense errors in any individual joint of the subjects in the training group were not different from those of the control subjects. Therefore, exercises specifically targeting individual muscles with low intensity may not be sufficient to improve shoulder joint position sense in healthy subjects. Future work is needed to further investigate which types of exercise are more effective in improving joint position sense, and the mechanisms associated with those changes.