Determinants of following headway in congested traffic

This paper reports on results of a study undertaken in the UK aimed at investigating factors affecting the car following process. An understanding of the factors affecting this complex decision making process is essential to a wide range of theoretical issues including driver workload, capacity and the modeling of freeway flow, as well as practical applications such as the design of in-vehicle driver aids and assistance systems, many of which have direct relevance to increasing driver safety. The study used an instrumented vehicle to collect time dependent following data for a group of test drivers. Data was collected on two differing types of high speed road, using six primary subjects who drove a test vehicle, supplemented by data on 123 drivers that were observed following the test vehicle. Examination was made of how the time headway chosen by a driver is influenced by a range of situational variables commonly believed to effect behavior, with four main findings. Firstly, headway was found to change according to the type of vehicle being followed (i.e. subjects followed closer to trucks than to cars), secondly, little variation was found with changes in overall traffic flow, thirdly, little correlation was found with road type, and lastly a distinct day-to-day variation in individual behavior was observed.     

Research quality considerations for grounded theory research in sport & exercise psychology

ObjectivesThe aims of this article are: to examine the application of grounded theory in sport and exercise psychology; to locate such applications within broader grounded theory methodological debates and; to support the future use and evolution of the method in the field.MethodsA search of the four sport and exercise psychology journals with the highest impact factors in 2007 (Psychology of Sport and Exercise, Journal of Sport and Exercise Psychology, Journal of Applied Sport Psychology and The Sport Psychologist) using the search term “grounded theory” and the date parameters 2000–2008 was conducted. These articles were discussed in relation to research quality concerns for grounded theory at the micro- and macro-level.ResultsTwelve articles were returned from the search. At the micro-level, eight elements representing collective sufficient conditions for grounded theory were discussed, which only two of the twelve articles returned met. Examples of common mistakes in relation to these elements were provided from the twelve articles. At the macro-level, the ontological and epistemological debates surrounding variants of grounded theory were discussed. Only one of the twelve articles explicitly recognised that there are variants of grounded theory, whilst the potential to generate more generic formal theory, and thus make a wider contribution to bodies of knowledge, was not discussed in any of the articles.ConclusionsThere are research quality concerns regarding the application of grounded theory in sport and exercise psychology at the micro- and macro-level, largely linked to a lack of understanding of the methodology and its implementation. Suggestions to address this for editors, reviewers and authors are offered.     

The role of color in human face detection

Significant advances have been made in understanding human face recognition . However, a fundamental aspect of this process, how faces are located in our visual environment, is poorly understood and little studied. Here we examine the role of color in human face detection. We demonstrate that detection performance declines when color information is removed from faces, regardless of whether the surrounding scene context is rendered in color. Furthermore, faces rendered in unnatural colors are hard to detect, suggesting a role beyond simple segmentation. When faces are presented such that half the surface is colored appropriately, and half unnaturally, performance declines. This suggests that observers are not simply using the presence of skin color "patches" to detect faces. Rather, our data suggest that detection operates via a face template combining diagnostic color and face-shape information. These findings are consistent with color-template approaches used in some computer-based face detection systems.     

Ovals of time: time-space associations in synaesthesia

We examine a condition in which units of time, such as months of the year, are associated with specific locations in space. For individuals with this time-space synaesthesia, contiguous time units such as months are spatially linked forming idiosyncratically shaped patterns such as ovals, oblongs or circles. For some individuals, each time unit appears in a highly specific colour. For instance, one of the synaesthetes we studied experienced December as a red area located at arms length to the left of their body. For the same individual May was a blue area located roughly at arms length to the right of their body. We studied four synaesthetes who report spatial associations for the months of the year. We found that the time-space associations experienced by these individuals were consistent across test-retest. In addition, month names directed visual attention to particular locations in space. For some synaesthetes, this directing of spatial attention was quite rapid-in accord with their reports that month names involuntarily bring to mind spatial locations.     

Emotion simulation during language comprehension

We report a novel finding on the relation of emotion and language. Covert manipulation of emotional facial posture interacts with sentence valence when measuring the amount of time to judge valence (Experiment 1) and sensibility (Experiment 2) of the sentence. In each case, an emotion-sentence compatibility effect is found: Judgment times are faster when facial posture and sentence valence match than when they mismatch. We interpret the finding using a simulation account; that is, emotional systems contribute to language comprehension much as they do in social interaction. Because the effect was not observed on a lexical decision task using emotion-laden words (Experiment 3), we suggest that the emotion simulation affects comprehension processes beyond initial lexical access.     

A bottleneck in face identification: repetition priming from flanker images

There is evidence that face processing is capacity-limited in distractor interference tasks and in tasks requiring overt recognition memory. We examined whether capacity limits for faces can be observed with a more sensitive measure of visual processing, by measuring repetition priming of flanker faces that were presented alongside a face or a nonface target. In Experiment 1, we found identity priming for face flankers, by measuring repetition priming across a change in image, during task-relevant nonface processing, but not during the processing of a concurrently-presented face target. Experiment 2 showed perceptual priming of the flanker faces, across identical images at prime and test, when they were presented alongside a face target. In a third Experiment, all of these effects were replicated by measuring identity priming and perceptual priming within the same task. Overall, these results imply that face processing is capacity limited, such that only a single face can be identified at one time. Merely attending to a target face appears sufficient to trigger these capacity limits, thereby extinguishing identification of a second face in the display, although our results demonstrate that the additional face remains at least subject to superficial image processing.     

Hits and false positives in face matching: a familiarity-based dissociation

In recognition memory for unfamiliar faces, performance for target-present items (hits) does not correlate with performance for target-absent items (false positives), a result which runs counter to the more usual mirror effect. In this paper we examinesubjects' performance on fac e matching, a nd demonstrate no relationship-between performance on matching items and performance on nonmatching items. This absence of a mirror effect occurs for multidistractor, 1-in-10 matching tasks (Experiment 1) and for simple paired-item tasks (Experiment 2). In Experiment 3 we demonstrate that matching familiar faces produces a strong mirror effect. However, inverting the familiar faces causes the association to disappear once more (Experiment 4). We argue thatfamiliar and unfamiliar faces are represented in qualitatively different ways.     

Avoidance of emotional facial expressions in social anxiety: The Approach-Avoidance Task

The Approach–Avoidance Task (AAT) was employed to indirectly investigate avoidance reactions to stimuli of potential social threat. Forty-three highly socially anxious individuals (HSAs) and 43 non-anxious controls (NACs) reacted to pictures of emotional facial expressions (angry, neutral, or smiling) or to control pictures (puzzles) by pulling a joystick towards themselves (approach) versus pushing it away from themselves (avoidance). HSAs showed stronger avoidance tendencies than NACs for smiling as well as angry faces, whereas no group differences were found for neutral faces and puzzles. In contrast, valence ratings of the emotional facial expressions did not differ between groups. A critical discrepancy between direct and indirect measures was observed for smiling faces: HSAs evaluated them positively, but reacted to them with avoidance.     

Scottish secondary school teachers' attitudes towards, and conceptualisations of, counselling

This paper presents the findings of two independent questionnaire studies that examined Scottish secondary schools teachers' attitudes towards, and conceptualisation of, school counselling. Seventy-one teachers in a first study, and 33 teachers in a second study, responded to a range of qualitative and quantitative response-format questions that were designed to elicit their feelings and attitudes towards school counselling, and their notions of what counselling was. Results from the two studies confirm previous findings in this area, suggesting that teachers are generally positive in their attitudes towards counselling; valuing, in particular, the independence and expertise of the counsellor. A small minority of teachers, however, were found to hold strongly negative views towards counselling. Teachers also expressed concerns that students might abuse the counselling service, and that the service might not fully integrate with existing guidance arrangements provided by teachers in schools. The study also found that a high proportion of teachers conceptualised counselling in terms of advice-giving.