On Modal Logics Characterized by Models with Relative Accessibility Relations: Part I

This work is divided in two papers (Part I and Part II). In Part I, we study a class of polymodal logics (herein called the class of "Rare-logics") for which the set of terms indexing the modal operators are hierarchized in two levels: the set of Boolean terms and the set of terms built upon the set of Boolean terms. By investigating different algebraic properties satisfied by the models of the Rare-logics, reductions for decidability are established by faithfully translating the Rare-logics into more standard modal logics. The main idea of the translation consists in eliminating the Boolean terms by taking advantage of the components construction and in using various properties of the classes of semilattices involved in the semantics. The novelty of our approach allows us to prove new decidability results (presented in Part II), in particular for information logics derived from rough set theory and we open new perspectives to define proof systems for such logics (presented also in Part II).     

Dorsal stream deficits suggest hidden dyslexia among deaf poor readers: correlated evidence from reduced perceptual speed and elevated coherent motion detection thresholds

Prelingual deafness and developmental dyslexia have confounding developmental effects on reading acquisition. Therefore, standard reading assessment methods for diagnosing dyslexia in hearing people are ineffective for use with deaf people. Recently, Samar, Parasnis, and Berent (2002) reported visual evoked potential evidence that deaf poor readers, compared to deaf good readers, have dorsal stream visual system deficits like those previously found for hearing dyslexics. Here, we report new psychometric and psychophysical evidence that deficits in dorsal stream function, likely involving extrastriate area MT, are associated with relatively poor reading comprehension in deaf adults. Poorer reading comprehension within a group of 23 prelingually deaf adults was associated with lower scores on the Symbol Digit Modality Test, a perceptual speed test commonly used to help identify dyslexia in hearing people. Furthermore, coherent dot motion detection thresholds, which reflect the functional status of area MT, correlated negatively with reading scores in each visual quadrant. Elevated motion thresholds for deaf poor readers were not due to general cognitive differences in IQ but were specifically correlated with poor perceptual speed. With IQ controlled, a highly reliable right visual field advantage for coherent motion detection was found. Additional analyses suggested that the functional status of dorsal stream motion detection mechanisms in deaf people is related to reading comprehension, but the direction and strength of lateralization of those mechanisms is independent of reading comprehension. Our results generally imply that dyslexia is a hidden contributor to relatively poor reading skill within the deaf population and that assessment of dorsal stream function may provide a diagnostic biological marker for dyslexia in deaf people.     

Trunk coordination in healthy and chronic nonspecific low back pain subjects during repetitive flexion–extension tasks: Effects of movement asymmetry,velocity and load

Multiple joint interactions are critical to produce stable coordinated movements and can be influenced by low back pain and task conditions. Inter-segmental coordination pattern and variability were assessed in subjects with and without chronic nonspecific low back pain (CNSLBP). Kinematic data were collected from 22 CNSLBP and 22 healthy volunteers during repeated trunk flexion–extension in various conditions of symmetry, velocity, and loading; each at two levels. Sagittal plane angular data were time normalized and used to calculate continuous relative phase for each data point. Mean absolute relative phase (MARP) and deviation phase (DP) were derived to quantify lumbar–pelvis and pelvis–thigh coordination patterns and variability. Statistical analysis revealed more in-phase coordination pattern in CNSLBP (p = 0.005). There was less adaptation in the DP for the CNSLBP group, as shown by interactions of Group by Load (p = .008) and Group by Symmetry by Velocity (p = .03) for the DP of pelvis–thigh and lumbar–pelvis couplings, respectively. Asymmetric (p < 0.001) and loaded (p = 0.04) conditions caused less in-phase coordination. Coordination variability was higher during asymmetric and low velocity conditions (p < 0.001). In conclusion, coordination pattern and variability could be influenced by trunk flexion–extension conditions. CNSLBP subjects demonstrated less adaptability of movement pattern to the demands of the flexion–extension task.     

孤独症谱系障碍者的生物运动探测障碍：基于行为与神经的证据

关于孤独症谱系障碍个体探测生物运动的能力是否受损,已有行为研究尚存分歧。导致分歧的原因可能是实验刺激、实验任务和测量指标存在差异。然而,神经研究却一致证实其潜在的神经机制存在异常。领域特殊性观点认为该障碍可能是基于后侧颞上沟功能异常的社会性功能障碍,也可能是基于镜像神经元功能异常的社会性功能障碍;而领域一般性观点认为该障碍可能是基于背侧视觉流功能异常的视运动知觉障碍,也可能基于脑功能联结异常的弱中央统合障碍。据此,本文将从研究范式、行为表现及潜在机制三个方面梳理相关研究,以期为后续研究提供新方向。     

Changes in Saccadic and Manual Motor Control After Ocular Smooth Pursuit Adaptive Modifications

The gain of ocular smooth pursuit responses can be adaptively modified under certain circumstances. Evidence that these modifications are caused, at least partly, by changes at a sensory level comes from the fact that subsequent manual tracking movements generated during visual fixation are also modified in a similar manner. The question addressed in the present experiment was whether the modifications are constrained specifically to responses such as these, which are driven by retinal image motion, or whether they can also influence movements that make use of retinal image position. This was accomplished by comparing manual and oculomotor responses to step changes in target position before and after smooth pursuit adaptation. The results showed that, as with manual tracking movements, these responses were also modified by the adaptive procedure, although to a lesser extent. In particular, following a 20-min period in which subjects (N = 4) were submitted to a procedure designed to increase the gain of the smooth pursuit system, manual step tracking movements and ocular saccades displayed larger amplitudes than those shown prior to the adaptation. In addition, these gain changes were accompanied by appropriate alterations in response kinematics. Taken together, these results suggest that the mechanisms responsible for adaptive modifications in the smooth pursuit system are also able to more generally influence the processing of visuospatial information. The possible neurophysiological substrate underlying these mechanisms is discussed.     

“In‐Group Love” and “Out‐Group Hate” in Repeated Interaction Between Groups

Costly individual participation in intergroup conflict can be motivated by “in‐group love”—a cooperative motivation to help the in‐group, by “out‐group hate”—an aggressive or competitive motivation to hurt the out‐group, or both. This study employed a recently developed game paradigm (Halevy, Bornstein, & Sagiv, 2008) designed specifically to distinguish between these two motives. The game was played repeatedly between two groups with three players in each group. In addition, we manipulated the payoff structure of the interaction that preceded the game such that half of the groups experienced peaceful coexistence and the other half experienced heightened conflict prior to the game. Enabling group members to express in‐group love independently of out‐group hate significantly reduced intergroup conflict. Group members strongly preferred to cooperate within their group, rather than to compete against the out‐group for relative standing, even in the condition in which the repeated game was preceded by conflict. Although both “in‐group love” and “out‐group hate” somewhat diminished as the game continued (as players became more selfish), choices indicative of the former motivation were significantly more frequent than choices indicative of the latter throughout the interaction. We discuss the implications of these findings for conflict resolution. Copyright © 2011 John Wiley & Sons, Ltd.     

Representational momentum in older adults

Humans have a tendency to perceive motion even in static images that simply “imply” movement. This tendency is so strong that our memory for actions depicted in static images is distorted in the direction of implied motion - a phenomenon known as representational momentum (RM). In the present study, we created an RM display depicting a pattern of implied (clockwise) rotation of a rectangle. Young adults viewers’ memory of the final position of the test rectangle was biased in the direction of continuing rotation, but older adults did not show a similar memory bias. We discuss several possible explanations for this group difference, but argue that the failure of older adults to shown an RM effect most likely reflects age-related changes in areas of the brain involved in processing real and implied motion.     

Two-step communication for the interaction between automated vehicles and pedestrians

An important challenge of automated vehicles (AV) will be the cooperative interaction with surrounding road users such as pedestrians. One solution to compensate for the missing driver-pedestrian interaction might be explicit communication via external human machine interfaces (eHMIs). Additionally, implicit communication such as a vehicle pitch motion might support AVs when interacting with pedestrians. While previous work explored various explicit and implicit communication cues, these concepts communicated the intention of the AV at one single time point. Currently, empirical findings on two-step communication lack so far. In this study, we empirically test the effect of a two-step AV communication that uses an implicit cue at a long distance and subsequently provides an implicit or explicit cues at a short distance. We compared its efficiency to single-step communication concepts providing implicit or explicit cues at the shorter distance only. To explore whether the right communication cue is used at the right distance, we analyzed pedestrians’ fixations while approaching an AV using an eye tracking device.We conducted a virtual reality study (N = 30) with AV communication concept that provided an active pitch motion or an eHMI and compared them with a two-step AV communication concept that provided an additional active pitch motion at a long distance when approaching the pedestrian. Furthermore, we recorded pedestrians’ fixation behavior while the AV approached.Consistently to previous work, single-step AV communication showed a beneficial effect on crossing behavior. Pedestrians initiated their crossing earlier while approaching an AV with an active pitch motion or an eHMI compared to the baseline condition. While active pitch motion reduced subjective safety feeling, eHMI increased it. However, the two-step communication concept did not further improve pedestrians’ crossing initiation times and their safety feeling. The pattern of fixation behavior differed as a function of AV distance. When the approaching AV was far away, pedestrians exclusively looked at the environment. During the approach, pedestrians gradually fixated the bumper and the hood and only then the windshield of the AV. Hence, it seems to be useful to present an AV intent communication at a certain distance from the pedestrian. These findings posit the importance of considering pedestrians’ fixation behavior when developing communication concepts between AVs and pedestrians.     

Increasing the conspicuity of cyclists at night by using bicycle lights and clothing to highlight their biological motion to oncoming drivers

Reduced conspicuity is an important contributing factor to increased motor vehicle-bicycle crashes and cyclist fatalities at night. This study explored ways of making night-time cyclists more conspicuous to oncoming vehicles through cyclist clothing options and bicycle light position. Fifteen young participants (M = 29.1 ± 4.5 years) drove a closed-road at night and indicated when they first recognized a cyclist pedalling in place at the roadside, facing the approaching vehicle. The bicycle had a static forward-facing white light located either on the handlebars or the helmet and wore one of five clothing configurations: fluorescent vest, retroreflective vest, retroreflective ankle strips, retroreflective vest plus retroreflective ankle strips, retroreflective vest plus biomotion retroreflective strips. There was a significant effect of light position (p < 0.001) and clothing (p < 0.001), where recognition distances were longer when the light was helmet-mounted and when retroreflective strips were worn on the lower legs to highlight the cyclist’s biological motion compared to either of the vest conditions. There was also a significant interaction between light position and clothing (p = 0.007) such that the benefit of retroreflective strips was greater when the bicycle light was helmet-mounted rather than on the handlebars. Importantly, the benefits of leg markings were apparent even when positioned at the ankles alone. These findings highlight that retroreflective material is most useful for improving cyclist conspicuity at night when positioned on cyclists’ lower legs, particularly the ankles (highlighting the cyclist's pedalling motion), rather than on the torso, and have important practical implications for maximising cyclists’ conspicuity and hence safety on night-time roads.     

城镇化进程中离乡农民心理健康特点调查及心理素质、相对剥夺感的影响机制

为探讨城镇化进程中离乡农民的心理健康特点以及心理素质、相对剥夺感对其的影响,通过量表对1339名城乡居民进行调查。结果发现:离乡与留乡农民在幸福感、拥有生命意义感、感知控制感、心理素质方面显著低于城镇居民,在状态焦虑方面显著高于城镇居民; 离乡农民在抑郁上显著高于城镇居民,在感知控制感上显著高于留乡农民,在心理素质上显著低于留乡农民; 留乡农民在相对剥夺感上显著高于城镇居民; 离乡农民的幸福感、拥有生命意义感、感知控制感态与相对剥夺感呈显著负相关,与心理素质呈显著正相关; 离乡农民的抑郁、状态焦虑与相对剥夺感呈显著正相关,与心理素质呈显著负相关; 离乡农民的相对剥夺感与心理素质之间呈显著负相关。心理素质除了可以直接预测心理健康各项指标,还可以通过相对剥夺感的中介作用,间接预测幸福感、抑郁及状态焦虑。提升心理素质和降低相对剥夺感是离乡农民心理健康服务的重要切入点。