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.     

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.     

'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.     

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.     

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.     

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.     

A virtual training institute in Eastern Europe

This is a short outline of the development of psychoanalysis and of analytic training in Eastern Europe after the fall of the Iron Curtain. The Han Groen Prakken Psychoanalytic Institute for Eastern Europe was founded by the IPA and the EPF in 2002 to organize and coordinate this. The activity of such an unusual training institute, virtual and time-limited up to the birth of new IPA study groups, is described with the problems it has had to face, from shuttle analysis to research of this unusual training, from initial outreach activity to formation of new analytic groups, from unavoidable plurality of analytic approaches of an international staff to the need for systematic teaching, from criteria for selection of candidates in such a large area with many languages, cultures and histories, to the integration of new analysts and groups in the international analytic community. These problems are part of the challenge implicit in the globalization, with its unavoidable push to enlarge to the whole humanity the psychoanalytic theory and praxis. Such an experience is now used in Latin America, but may also soon have its application in other continents. Freedom of mind is a basic need of all humans and psychoanalysis still has much to say about this.     

Remembering the place with the tiger: Survival processing can enhance source memory

Rating the relevance of words for survival in the grasslands of a foreign land often leads to a memory advantage. However, it is as yet unclear whether the survival processing effect generalizes to source memory. Here, we examined whether people have enhanced source memory for the survival context in which an item has been encountered. Participants were asked to make survival-based or moving-based decisions about items prior to a classical source memory test. A multinomial model was used to measure old–new discrimination, source memory, and guessing biases separately. We replicated the finding of a survival advantage in old–new recognition. Extending previous results, we also found a survival-processing advantage in source memory. These results are in line with the richness-of-encoding explanation of the survival processing advantage and with an adaptive perspective on memory.     

Syntactic complexity and information transmission in first-graders: A cross-cultural study

Some differences between child and adult communication are due to general developmental immaturity and some to language-specific factors. The Piagetan concept of syncretism exemplifies an hypothecated universal of psycholinguistic development, and it results in child texts characterized by minimally structured temporal, causal, and logical connections. A different sort of problem is that, within a specific language, certain syntactic items may fail to mature in children at the expected rate, because of structural oddities of the constructions. English has several such constructions, generally peculiar in their conflict between surface- and deep-structure subject of the main verb. It is predictable that a syncretistic child attempting to deal with such items in a text will analyze them according to the surface-structure analogic method which defines verbal syncretism, and so will fail to make sense of them. Finally, cutting across these child language features are others peculiar to the language of specific groups of children, such as the putative communication impairment of the disadvantaged black child, whose language has been described by some researchers as less efficient and slower to mature than that of others. Clearly, if this is so, then black children's language should at any young age show more evidence of syncretistic communicative immaturity as well as slower development of adult syntactic patterns. The present paper, then, investigates on a cross-cultural basis the dual hypotheses of syncretism and faulty mastery of difficult syntax, by means of an experimental story-repeating format first used by Piaget. Hypotheses are examined for the cause of children's distinctive communication technique, and the whole question of the significance of black/white differences in communicative style and verbal maturity is discussed.     

Symmetry, gestalt and information theory: A critique

A criticism of a recent analysis of matrix pattern perception is advanced. It is pointed out that a fair test of the equivalence for performance of different forms of redundancy must be framed in terms of the measure of transmitted information.     

Presence and emotions in virtual environments: the influence of stereoscopy.

This study investigates how stereoscopy (the illusion of depth and 3D imaging) affects the sense of presence and the intensity of the positive mood that users feel in virtual environments (VEs). A between-group design was used, and 40 volunteers were randomly assigned to one of two experimental conditions (stereoscopy vs. no stereoscopy) and to one of two emotional VEs (relaxation or joy). The participants' emotions were assessed before and after the VR experience. Presence was measured with two postexperiment questionnaires (ITC-SOPI and SUS). Results show that there were no differences between stereoscopic and monoscopic presentations in VEs (neither subjective sense of presence nor emotional reactions). Practical and theoretical implications of these findings are discussed herein.     

Knowledge-based information acquisition: norms and the functions of consensus information

Mill's (1872/1973) method of difference prescribes that the lay scientist should use consensus information as a control condition for the person and distinctiveness information as a control condition for the stimulus when analyzing their causal effects on the occurrence of the target event. However, in studies of information acquisition, subjects have shown a consistent preference for distinctiveness information when answering causal questions about the person, and for consensus information when answering causal questions about the stimulus. To explain this discrepancy, we distinguish between the evaluative, contrastive, and corroborative functions of consensus and distinctiveness information. In addition, we suggest that subjects seek consensus information only if it is relevant to the question posed to them, and if they cannot supply it from their own presupposed knowledge of behavioral norms. We report four information acquisition experiments that provide support for our analysis.