The tiger on your tail: choosing between temporally extended behaviors

The time spent choosing between temporally extended behaviors cannot, in general, last as long as the behaviors themselves; otherwise, the tiger on your tail would have you for lunch. Previous reaction time studies provide little information on this topic, which was explored in the study reported here by showing participants images of scenes for which they could choose a left or right walking-and-reaching path. The paths they chose were nearly identical to ones chosen by participants who actually performed the task in a previous study. Moreover, the times participants took to choose the actions were about 5 times shorter than the times it took to perform them. The choice-time data were inconsistent with the idea that participants picked the path with a lower cost after mentally simulating the paths one after the other. Showing real-world scenes and having participants choose actions for them holds promise for future research in cognitive psychology, ecological psychology, and behavioral ecology.     

Learning your way around town: how virtual taxicab drivers learn to use both layout and landmark information

By having subjects drive a virtual taxicab through a computer-rendered town, we examined how landmark and layout information interact during spatial navigation. Subject-drivers searched for passengers, and then attempted to take the most efficient route to the requested destinations (one of several target stores). Experiment 1 demonstrated that subjects rapidly learn to find direct paths from random pickup locations to target stores. Experiment 2 varied the degree to which landmark and layout cues were preserved across two successively learned towns. When spatial layout was preserved, transfer was low if only target stores were altered, and high if both target stores and surrounding buildings were altered, even though in the latter case all local views were changed. This suggests that subjects can rapidly acquire a survey representation based on the spatial layout of the town and independent of local views, but that subjects will rely on local views when present, and are harmed when associations between previously learned landmarks are disrupted. We propose that spatial navigation reflects a hierarchical system in which either layout or landmark information is sufficient for orienting and wayfinding; however, when these types of cues conflict, landmarks are preferentially used.     

Spatial updating in virtual reality: the sufficiency of visual information

Robust and effortless spatial orientation critically relies on "automatic and obligatory spatial updating", a largely automatized and reflex-like process that transforms our mental egocentric representation of the immediate surroundings during ego-motions. A rapid pointing paradigm was used to assess automatic/obligatory spatial updating after visually displayed upright rotations with or without concomitant physical rotations using a motion platform. Visual stimuli displaying a natural, subject-known scene proved sufficient for enabling automatic and obligatory spatial updating, irrespective of concurrent physical motions. This challenges the prevailing notion that visual cues alone are insufficient for enabling such spatial updating of rotations, and that vestibular/proprioceptive cues are both required and sufficient. Displaying optic flow devoid of landmarks during the motion and pointing phase was insufficient for enabling automatic spatial updating, but could not be entirely ignored either. Interestingly, additional physical motion cues hardly improved performance, and were insufficient for affording automatic spatial updating. The results are discussed in the context of the mental transformation hypothesis and the sensorimotor interference hypothesis, which associates difficulties in imagined perspective switches to interference between the sensorimotor and cognitive (to-be-imagined) perspective.     

'Let your fingers do the walking': the use of telephone helplines in career information and guidance

The UK Learndirect helpline, launched in February 1998, is the largest telephone helpline service in the guidance field so far developed in the world. By the end of 2000 it had responded to 2.4 million calls. The development of the helpline is placed in the context of the transformations in service delivery in other sectors, including the growth of callcentres and helplines. The use of the telephone in career guidance, both in the UK and elsewhere, is reviewed. The evolution of Learndirect is described, with particular attention to its policy context. The current operation of the service is outlined, including its extent, availability, staffing and users. Finally, a number of issues illuminated by the experiences of Learndirect are identified, including the place of in-depth guidance within helpline services, their relationship to wider guidance provision, their impartiality, their framing in relation to national/local, adult/all-age and learning/career dimensions, the synergy of helplines with other forms of technically mediated service delivery, and the implications of helpline work for the professional development of guidance staff.     

A virtual reality scenario for all seasons: the virtual classroom

Treatment and rehabilitation of the cognitive, psychological, and motor sequelae of central nervous system dysfunction often relies on assessment instruments to inform diagnosis and to track changes in clinical status. Typically, these assessments employ paper-and-pencil psychometrics, hands-on analog/computer tests, and rating of behavior within the context of real-world functional environments. Virtual reality offers the option to produce and distribute identical "standard" simulation environments in which performance can be measured and rehabilitated. Within such digital scenarios, normative data can be accumulated for performance comparisons needed for assessment/diagnosis and for treatment/rehabilitation purposes. In this manner, reusable archetypic virtual environments constructed for one purpose can also be applied for applications addressing other clinical targets. This article will provide a review of such a retooling approach using a virtual classroom simulation that was originally developed as a controlled stimulus environment in which attention processes could be systematically assessed in children with attention-deficit/hyperactivity disorder. This system is now being applied to other clinical targets including the development of tests that address other cognitive functions, eye movement under distraction conditions, social anxiety disorder, and the creation of an earthquake safety training application for children with developmental and learning disabilities.     

The information for catching fly balls: judging and intercepting virtual balls in a CAVE

Visually guided action implies the existence of information as well as a control law relating that information to movement. For ball catching, the Chapman Strategy--keeping constant the rate of change of the tangent of the elevation angle (d(tan(alpha))/dt)--leads a catcher to the right location at the right time to intercept a fly ball. Previous studies showed the ability to detect the information and the consistency of running patterns with the use of the strategy. However, only direct manipulation of information can show its use. Participants were asked to intercept virtual balls in a Cave Automated Virtual Environment (CAVE) or to judge whether balls would pass behind or in front of them. Catchers in the CAVE successfully intercepted virtual balls with their forehead. Furthermore, the timing of judgments was related to the patterns of changing d(tan(alpha))/dt. The advantages and disadvantages of a CAVE as a tool for studying interceptive action are discussed.     

Walking with avatars: Gait-related visual information for following a virtual leader

Dynamic situations, such as interactive sports or walking on a busy street, impose high demands on a person’s ability to interact with (others in) its environment (i.e., ‘interact-ability’). The current study examined how distance regulation, a fundamental component of these interactions, is mediated by different sources of visual information. Participants were presented with a back and forwards moving virtual leader, which they had to follow by walking back and forwards themselves. We presented the leader in several appearances that differed in the presence of segmental (i.e., relative movements of body segments), cadence-related (i.e., sway and bounce), and global (i.e., optical expansion-compression) information. Results indicated that removing segmental motion information from the virtual leader significantly deteriorated both temporal synchronization and spatial accuracy of the follower to the leader, especially when the movement path of the leader was less regular/predictable. However, no difference was found between cadence-related and global motion information appearances. We argue that regulating distance with others effectively requires a versatile attunement to segmental and global motion information depending on the specific task demands. The results further support the notion that detection of especially segmental information allows for more timely ‘anticipatory’ tuning to another person’s locomotor movements and intentions.     

The virtual haptic display: A device for exploring 2-D virtual shapes in the tactile modality

In order to understand better the processes involved in the perception of shape through touch, someelement of control is required over the nature of the shape presented to the hand and the presentation timing. To that end, we have developed a cost-effective, computer-controlled apparatus for presenting haptic stimuli using active touch, known as a virtual haptic display (VHD). The operational principle behind this device is that it translates black and white visual images into topographic, 2-D taxel (tactile pixel) arrays, along the same principle using in Braille letters. These taxels are either elevated or depressed at any one time representing white and black pixel colors of the visual image, respectively. To feel the taxels, the participant places their fingers onto a carriage which can be moved over the surface of the device to reveal a virtual shape. We conducted two experiments and the results show that untrained participants are able to recognize different, simple and complex, shapes using this apparatus. The VHD apparatus is therefore ideal at presenting 2-Dshapes through touch alone. Moreover,this device and its supporting software can also be used for presenting computer-controlled stimuli in cross-modal experiments.     

Mosaic trisomy 20 and mitigation in capital crimes sentencing: A review and case report

Trisomy 20 is a genetic abnormality in which individuals have an extra copy of chromosome 20. Complete trisomy 20 is rare and believed to be incompatible with life. A mosaic form of trisomy 20, in which only some cells or tissues contain the extra chromosome, is a relatively commonly encountered chromosomal abnormality found during prenatal testing, and c. 90% result in a normal phenotype. However, despite the absence of a consistent phenotype, certain findings have been reported across multiple cases of mosaic trisomy 20. These include an array of morphological findings, developmental delays, and learning disabilities. Beyond physical manifestations, a wide range of developmental and learning delays have also been reported. In this work, we provide an overview of the trisomy 20 literature and a case report of a young adult male with mosaic trisomy 20 who committed homicide. His developmental and life history, eventual diagnosis of mosaic trisomy 20, similarities and differences in his condition compared with prior research findings, and potentially new phenotypic findings associated with trisomy 20 that he manifested (childhood visual hallucinations, self‐injury, polydactyly) are presented. Additionally, the potential role of this genetic diagnosis in his neuropsychiatric history and its successful application as a mitigating factor at his capital sentencing trial are described. We did not identify other similar cases during our search of major scientific and legal databases. As a backdrop, the use of genetics in criminal trials is on the rise, and courts are increasingly likely to accept behavioral genetics evidence; therefore, it is crucial that the legal system is well acquainted with the opportunities and limitations of these approaches.     

Managing information overload in virtual teams: Effects of a structured online team adaptation on cognition and performance

Information overload (IO) indicates the exchange of too much low-quality information in virtual teams. When being overloaded with information, teams need to adapt and to change communication behaviour. This study introduces and tests a structured online team adaptation (STROTA) procedure that enables virtual teams to reduce IO by improving their team mental model quality. STROTA, built from team adaptation models, is a moderated intervention consisting of three stages: (1) individual situation awareness, (2) team situation awareness, and (3) plan formulation. STROTA was tested in the context of an experimental problem-solving task. Participants (N = 363) worked in virtual teams of three and were randomly assigned to one of four experimental conditions: no STROTA, incomplete STROTA (step 1, steps 1–2), and complete STROTA (steps 1–2–3). We found teams that followed a complete STROTA procedure experienced lessened IO over time. Teams with complete STROTA showed the largest development of TMM immediately after STROTA. Finally, multilevel mediation analyses showed that TMM are mediators that explain the influence of STROTA on IO.     

Acting your avatar’s age: effects of virtual reality avatar embodiment on real life walking speed

ABSTRACT

When immersive virtual reality users employ digital self-representations, i.e., avatars, they may be subject to the Proteus effect. This effect describes changes in attitudes and behaviors in accordance with identity cues derived from the employed avatar’s appearance, which can persist after leaving virtual reality. Individual reactions to the experience can affect the strength of observed Proteus effects. Especially the experienced illusions of body ownership of avatars and of being in the virtual environment (spatial presence) have been discussed in this context. This study investigated a Proteus effect of avatar age on post-embodiment walking speed, with special focus on how body ownership and spatial presence moderated this effect. Participants who had previously embodied older avatars took significantly longer to walk a set distance than either young avatar or control group participants. This was only apparent during the first half of the walking phase, which may indicate fast decay rates of the effect after embodiment ended. The reported body ownership could not be shown to impact the strength of the Proteus effect. Participants reporting more pronounced spatial presence were subject to stronger Proteus effects, with only the two-thirds of the sample with higher spatial presence showing evidence of the effect.     

Killing your children to hurt your partner: A South African perspective on the motivations for revenge filicide

The aim of the study was to investigate the offence characteristics and motivations for revenge filicides. Revenge filicide is an act where one parent kills their own offspring for retribution to hurt and upset the other parent. The cases of 20 revenge filicide murderers (14 male and six female) were analysed to determine the motivations and offence characteristics of revenge filicide offenders. It is the first South African study to highlight the motivations and associated characteristics in revenge filicides. Themes such as a loss of social identity due to rejection; extreme rage type anger; external locus of control; sadism; a desire to cause pain and a need to inflict harm are highlighted in this article. The initial emotional response may escalate from mild anger to a level of narcissistic rage which eventually culminates in the murdering of the child to punish and hurt the other parent and to restore control.     

Correcting distance estimates by interacting with immersive virtual environments: effects of task and available sensory information

The tendency to underestimate egocentric distances in immersive virtual environments (VEs) is not well understood. However, previous research (A. R. Richardson & D. Waller, 2007) has demonstrated that a brief period of interaction with the VE prior to making distance judgments can effectively eliminate subsequent underestimation. Here the authors examine the mechanism underlying the effect of VE interaction and the conditions that may give rise to it. In Experiment 1, after interacting with an immersive VE, participants tended to overestimate distances in the physical world, indicating that the interaction involved a recalibration of the perceptual-motor system. Experiment 2 demonstrates that visual information is not necessary (and that body-based information is necessary) during the interaction period for it to have a positive effect on subsequent distance estimation accuracy. Experiment 3 illustrates that the interaction task does not need to be goal directed in order to be effective.     

Knowing your heart and your mind: The relationships between metamemory and interoception

Humans experience a unified self that integrates our mental lives and physical bodies, but many studies focus on isolated domains of self-knowledge. We tested the hypothesis that knowledge of one’s mind and body are related by examining metamemory and interoception. We evaluated two dimensions of metamemory and interoception: subjective beliefs and the accuracy of those beliefs compared to objective criteria. We first demonstrated, in two studies, that metamemory beliefs were positively correlated with interoceptive beliefs, and this was not due to domain-general confidence. Finally, we showed that individuals with better metamemory accuracy also had better interoceptive accuracy. Taken together, these findings suggest a common mechanism subserving knowledge of our cognitive and bodily states.     

I recognize your face, but I can't remember your name: A question of expertise?

In four experiments on the identification of familiar faces we reassessed a robust performance pattern—namely, the temporal advantage for retrieving biographical facts as compared to recalling proper names, which has been interpreted as reflecting a serial ordering of the access to semantic and name information. Evidence for recent parallel accounts had been provided by Scanlan and Johnston (1997) who reported an advantage for name retrieval in children. Here we replicated the findings of Scanlan and Johnston but also showed that the naming advantage disappears, and performance is very similar to that of adults when stimuli and tasks are used that are familiar to children. Conversely, we also demonstrated an advantage for name retrieval in adults when highly unfamiliar semantic facts were associated with the faces. Together these findings suggest that there is no fundamental difference in the cognitive architectures of children and adults. The experiments indicate that the relative speed of naming and semantic fact retrieval depends on the expertise with the semantic facts to be retrieved. Implications for models of face identification and naming are discussed.