Intercepting real and simulated falling objects: what is the difference?

International audience; The use of virtual reality is nowadays common in many studies in the field of human perception and movement control, particularly in interceptive actions. However, the ecological validity of the simulation is often taken for granted without having been formally established. If participants were to perceive the real situation and its virtual equivalent in a different fashion, the generalization of the results obtained in virtual reality to real life would be highly questionable. We tested the ecological validity of virtual reality in this context by comparing the timing of interceptive actions based upon actually falling objects and their simulated counterparts. The r…

Visually induced motion sickness and presence in videogames: The role of sound

Visually induced motion sickness (VIMS) is a well-known phenomenon in virtual environments, simulators, and videogames. We conducted an experiment to analyze the role of sound on the severity of VIMS and the feeling of presence in videogames. Thirty-two subjects first watched a pre-recorded sequence of the game “Mirrors Edge” and then played the game actively. Game-play sound was activated for half of the participants. VIMS was measured via the Simulator Sickness Questionnaire and the Fast Motion Sickness Scale, presence was captured using the Presence Questionnaire. Results showed severe VIMS in all participants during the passive video session, whereas active-play revealed only moderate …

The Effect of Central Vision Loss on Perception of Mutual Gaze

People with central vision loss (CVL) often report difficulties with social interactions and reduced social functioning.1, 2 A limited access to the nonverbal visual cues inherent to effective communication can be a disadvantage in social interactions. Wang and Boerner3 reported that for people with vision impairment, difficulty in social situations was due either to the individual’s own lack of ability to perceive visual cues or other people’s lack of understanding. The facial region has been noted as an important source of nonverbal visual information relevant to social situations.4 Prior studies of individuals with CVL due to age-related macular degeneration have focused primarily on dif…

Predictors of visually induced motion sickness in women

Abstract Background Visually induced motion sickness (VIMS) is commonly experienced when visual motion information is in conflict with motion information provided by the vestibular system and/or tactile and kinesthetic senses. According to some studies, women experience higher levels of VIMS than men, whereas other studies do not find this to be the case. Hypothesis This study investigated whether gender differences can be attributed to changes in VIMS-susceptibility due to the menstrual cycle and perceived menstrual pain. We hypothesized that higher perceived menstrual pain correlates positively with VIMS susceptibility. Methods We measured the influence of estimated concentrations of four…

Vestibular Stimulation Interferes with the Dynamics of An Internal Representation of Gravity

The remembered vanishing location of a moving target has been found to be displaced downward in the direction of gravity ( representational gravity) and more so with increasing retention intervals, suggesting that the visual spatial updating recruits an internal model of gravity. Despite being consistently linked with gravity, few inquiries have been made about the role of vestibular information in these trends. Previous experiments with static tilting of observers’ bodies suggest that under conflicting cues between the idiotropic vector and vestibular signals, the dynamic drift in memory is reduced to a constant displacement along the body's main axis. The present experiment aims to replic…

Effect of Camera Angle on Perception of Trust and Attractiveness

Film theories have long proposed that the vertical camera angle influences how the scene and the character in it are interpreted. An elevated camera (high-angle shot) should diminish the qualities of the actor, whereas a lowered camera (low-angle shot) should elevate the actor in perspective as well as in the viewer’s opinion. We were interested in how this holds up for the impression of trustworthiness and attractiveness that the spectator receives of the actor. We filmed 12 actors in a scenario inspired by a TV show called Split or Steal, which features a one-time version of the prisoner’s dilemma. Subjects had to rate trustworthiness and attractiveness of the actors, and also judge if t…

Non-Statements und Kohärenz

Nachdem wir uns in ▶ Kap. 4mit dem rationalistischen Wissenschaftsbild des Kritischen Rationalismus beschaftigt haben und in ▶ Kap. 5mit den empiristischen Positionen von Thomas Kuhn und der Frankfurter Schule, kommen wir jetzt zu zwei Positionen, die mehr als nur historische Bedeutung haben, da sie unser modernes Wissenschaftsverstandnis im 21. Jahrhundert leiten. Die modernen Positionen zeichnen sich dadurch aus, dass sie nicht mehr streng rationalistisch oder streng empiristisch sind, sondern gemasigtere Grundhaltungen verkorpern. Sie werden jedoch merken, dass es auch hier heute zwei grundlegend unterschiedliche Auffassungen gibt. Die eine, der sogenannte Non-Statement View von Joseph D…

Effect of Gaze on Personal Space: A Japanese–German Cross-Cultural Study

In East Asian cultures, people maintain larger interpersonal distances than in European or American cultures. We investigated whether a preference for averted gaze might be responsible for this difference. Typically, when measuring interpersonal distance, participants are asked to maintain eye contact. This request might bias findings due to cultural differences in the interpretation of direct gaze. We had Japanese and German participants adjust preferred interpersonal distance in a standardized laboratory task, using averaged faces with straight-ahead or averted gaze direction. In line with previous findings, Japanese participants preferred overall larger interpersonal distances, and fema…

The Effects of Hemianopia on Perception of Mutual Gaze

Significance Individuals with left hemianopic field loss (HFL), especially with neglect history, may have greater difficulties than individuals with right HFL in judging the direction of another person's gaze. Purpose Individuals with HFL often show a spatial bias in laboratory-based perceptual tasks. We investigated whether such biases also manifest in a more real-world task, perception of mutual gaze direction, an important, nonverbal communication cue in social interactions. Methods Participants adjusted the eye position of a life-size virtual head on a monitor at a 1-m distance until (1) the eyes appeared to be looking straight at them, or (2) the eyes were perceived to be no longer loo…

The impact of rear-view mirror distance and curvature on judgements relevant to road safety

We report two experiments that investigate the impact of rear-view mirror distance and curvature on distance, spacing, and time-to-contact (TTC) judgements. The variation in mirror distance had a significant effect on TTC judgements, but only marginally influenced distance and spacing estimations. As mirror distance increased, TTC was overestimated, which is potentially dangerous. Control conditions with identical visual angles across different mirror distances revealed that effects were not solely caused by variation in visual angle. The impact of mirror curvature moderated the effect. While observers were unable to compensate for the mirror distance effect, they could do so for the distor…

The Louder, the Longer: Object Length Perception Is Influenced by Loudness, but Not by Pitch

Sound by itself can be a reliable source of information about an object&rsquo

Supplementary Material 1 - Supplemental material for A Case for Raising the Camera: A Driving Simulator Test of Camera-Monitor Systems

Supplemental material, Supplementary Material 1, for A Case for Raising the Camera: A Driving Simulator Test of Camera-Monitor Systems by Christoph Bernhard, René Reinhard, Michael Kleer and Heiko Hecht in Human Factors: The Journal of Human Factors and Ergonomics Society

Global flow impacts time-to-passage judgments based on local motion cues

AbstractWe assessed the effect of the coherence of optic flow on time-to-passage judgments in order to investigate the strategies that observers use when local expansion information is reduced or lacking. In the standard display, we presented a cloud of dots whose image expanded consistent with constant observer motion. The dots themselves, however, did not expand and were thus devoid of object expansion cues. Only the separations between the dots expanded. Subjects had to judge which of two colored target dots, presented at different simulated depths and lateral displacements would pass them first. Image velocities of the target dots were chosen so as to correlate with time-to-passage only…

Are you looking at me? The effects of hemianopia on perception of mutual gaze

Visual and postural eye-height information is flexibly coupled in the perception of virtual environments.

We conducted two experiments to investigate how observers integrate postural and visual eye-height information when estimating the layout of interior space. In Experiment 1, we varied postural and visual eye-height information independently of each other in a virtual-reality setup. Observers estimated the width, depth, and height of simulated rooms. All dimensions were perceived as larger when the virtual visual eye-height corresponded to sitting on the floor as compared with standing upright. In contrast, the estimates remained widely unaffected by the observer's physical posture (likewise sitting vs. standing). In Experiment 2, we studied effects of the viewing condition (real vs. virtual…

Effects of symmetry, texture, and monocular viewing on geographical slant estimation.

Hills often appear to be steeper than they are. The unusual magnitude of this error has prompted extensive experimentation. The judgment mode, such as verbal vs. action-based measures, the state of the observer - whether exhausted or well rested - all can influence perceived geographical slant. We hold that slant perception is inherently shaky as soon as the slope in question is no longer palpable, that is if it is outside our personal space. To make this point, we have added symmetry, texture, and depression to the list of factors that might modulate slant perception. When the frontal slope of a hill is to be judged, it appears steeper when the side slopes are steep. We have used model hil…

Luminance and contrast in visual perception of time to collision.

AbstractMany animals avoid dark, approaching objects seen against a lighter background but show no or weaker reactions to stimuli with inverted contrast. We investigated whether human observers would respond differently to such stimuli in terms of estimated time-to-arrival. We varied luminances of an approaching, light or dark disk and a plain, grey background, and for several conditions, continuously adjusted calibrations so as to keep contrast and/or overall lightness constant. Since no effects were found, we conclude that humans are able to discard luminance and contrast for the task at hand. Generally, however, performance was affected by different, consecutive regimes of feedback: Init…

SupplementaryMaterial_CeilingColor_finalSubmission – Supplemental material for Which Attribute of Ceiling Color Influences Perceived Room Height?

Supplemental material, SupplementaryMaterial_CeilingColor_finalSubmission for Which Attribute of Ceiling Color Influences Perceived Room Height? by Christoph von Castell, Heiko Hecht and Daniel Oberfeld in Human Factors: The Journal of Human Factors and Ergonomics Society

Visual discrimination of arrival times: Troublesome effects of stimuli and experimental regime

Canned Emotions. Effects of Genre and Audience Reaction on Emotions

Laughter is said to be contagious. Maybe this is why TV stations often choose to add so-called canned laughter to their shows. Questionable as this practice may be, observers seem to like it. If such a simple manipulation, assumingly by inducing positive emotion, can change our attitudes toward the film, does the opposite manipulation work as well? Does a negative sound-track, such as screaming voices, have comparable effects in the opposite direction? We designed three experiments with a total of 110 participants to test whether scream-tracks have comparable effects on the evaluation of film sequences as do laugh-tracks. Experiment 1 showed segments of comedies, scary, and neutral films an…

The CSI-education effect: Do potential criminals benefit from forensic TV series?

Abstract Forensic series have become popular over the last two decades. They have raised the importance of forensic evidence in the eyes of the public (CSI effect). However, it has not been investigated to what extent criminals may learn about forensic evidence through these shows. We used multiple approaches to tackle this potential CSI-education effect. First, we analyzed crime statistics for crime and detection rate. Second, we asked convicted criminals about their impressions about the usefulness of crime shows for covering up a crime. Third, we asked fans of crime series and a control group of non-watchers to slip into the role of a criminal by enacting the cleaning up a murder crime s…

Acceptance of truck platooning by professional drivers on German highways. A mixed methods approach.

Abstract Truck platoon driving is a current branch of automated driving, which has the potential to radically change the work routine of professional drivers. In a platoon system, one truck (semi-)automatically follows a lead truck with a reduced distance, which produces significant savings in fuel and enables better traffic flow. In a current application of truck platoon driving, the following vehicle operates at level-2 automation. Thus, the driver of the following truck merely has to supervise the semi-automated system, which takes over steering and speed control when engaged. Level-2 truck platoon driving had not been tested with professional drivers in real traffic before. We hypothesi…

Informationsverarbeitung und Kognitive Wende

Nachdem wir uns mit dem Behaviorismus beschaftigt haben, der mit erschreckender Radikalitat alle subjektive Erfahrung – und damit auch Kognitionen – aus dem Gegenstandsbereich der Psychologie eliminiert hatte, wollen wir jetzt kurz die Gegenbewegung, den Informationsverarbeitungsansatz in der Psychologie kennenlernen. Der Paradigmenwechsel vom Behaviorismus zur Informationsverarbeitung verdient durchaus diesen Kuhn’schen Ausdruck und wird kognitive Wendegenannt. Den Informationsverarbeitungsansatz kann man auch mit einem Kognitivismus gleichsetzen. Eine wichtige Station auf dem Weg dorthin oder, in Kuhns Worten, ein Ausloser fur die Krise des alten Paradigmas ist sicherlich in der Behaviori…

Interpersonal Distance in the SARS-CoV-2 Crisis

Background Mandatory rules for social distancing to curb the SARS-CoV-2 pandemic require individuals to maintain a critical interpersonal distance above 1.5 m. However, this contradicts our natural preference, which is closer to 1 m for non-intimate encounters, for example, when asking a stranger for directions. Objective This review addresses how humans typically regulate interpersonal distances, in order to highlight the challenges of enforcing atypically large interpersonal distances. Method To understand the challenges posed by social distancing requirements, we integrate relevant contributions from visual perception, social perception, and human factors. Results To date, research on pr…

Age-Correlated Incremental Consideration of Velocity Information in Relative Time-to-Arrival Judgments

International audience; One hundred fifty-one children and 43 adults judged which of 2 cartoon birds would be the first to arrive at a common finish line. Objects moved unidirectionally along parallel trajectories, either at the same or different speeds, and disappeared at different distances from the goal. Overall, 9-10-year-old children performed as well as adults, but 4-5- and 6-8-year-olds erred significantly more often. On trials for which distance to goal at disappearance was a valid cue, 4-5-year-olds scored 80% correct, and no differences were seen between 6-10-year-olds and adults. On the opposite type of trials, where the trailing bird would win the race, only adults retained thei…

Allocentric time-to-contact and the devastating effect of perspective

AbstractWith regard to impending object–object collisions, observers may use different sources of information to judge time to contact (tC). We introduced changes of the observer’s vantage point to test among three sets of hypotheses: (1) Observers may use a distance-divided-by-velocity algorithm or, alternatively, elaborated τ-formulae, all of which give exact tC information; (2) observers may use simple τ-formulae (i.e., formulae of the type: visual angle divided by its own first temporal derivative); (3) observers may capitalize on non-τ variables. Hypotheses (2) and (3) imply specific patterns of errors. We presented animated, impending collisions between a moving object and a stationar…

Internal consistency predicts attractiveness in biological motion walkers

Abstract Why do some people appear attractive to us while others don't? Evolutionary psychology states that sexual attractiveness has evolved to assess the reproductive qualities of a potential mate. Past research in the field has identified a number of traits that can be linked directly to qualities such as immuno-competence, developmental stability, and fertility. The current study is motivated by the hypothesis that attractiveness is determined not just by individual, independent traits, but also by whether their pattern is internally consistent. Exploiting the domain of biological motion, we manipulated internal consistency between anthropometry and kinematics of a moving body. In two e…

For the mind's eye the world is two-dimensional.

The nature of visual mental images is a topic that has puzzled neuroscientists, psychologists, and philosophers alike. On the one hand, mental images might preserve the 3-D properties of our perceptual world. On the other hand, they might be akin to 2-D pictures, such as photographs, paintings, or drawings. In the present study, 16 observers judged where real objects (Experiment 1) or photographs thereof (Experiment 2) were pointing. Both experiments contained a perception condition and an imagery condition. In Experiment 1, there was a significant difference between the pointing errors in the perception and the imagery conditions, whereas there was no such difference in Experiment 2. In im…

The effects of social pressure and emotional expression on the cone of gaze in patients with social anxiety disorder

Abstract Background and objectives Patients with social anxiety disorder suffer from pronounced fears in social situations. As gaze perception is crucial in these situations, we examined which factors influence the range of gaze directions where mutual gaze is experienced (the cone of gaze). Methods The social stimulus was modified by changing the number of people (heads) present and the emotional expression of their faces. Participants completed a psychophysical task, in which they had to adjust the eyes of a virtual head to gaze at the edge of the range where mutual eye-contact was experienced. Results The number of heads affected the width of the gaze cone: the more heads, the wider the …

How Long Did You Look At Me? The Influence of Gaze Direction on Perceived Duration and Temporal Sensitivity.

Faces that exhibit emotionally negative expressions in mutual gaze have been shown to induce a dilation of perceived duration. The influence of gaze by itself on duration judgments, however, has rarely been investigated. We argue for a social interaction hypothesis, according to which humans should be highly accurate and precise (sensitive) when processing the temporal dynamics of mutual gaze. In three experiments, we investigated whether the direction of observed gaze affects perceived duration and temporal sensitivity. In Experiment 1, subjects did indeed estimate the duration of direct gaze more accurately as compared to the duration of averted gaze. In Experiments 2 and 3, subjects had…

Brightness and contrast do not affect visually induced motion sickness in a passively-flown fixed-base flight simulator

Abstract Background Visually Induced Motion Sickness (VIMS) or simulator sickness is often elicited by a visual stimulus that lacks the appropriate vestibular or proprioceptive feedback. In this study, we chose to investigate the effects of brightness and contrast of the visual scene on VIMS. Hypothesis We hypothesized that visual environments differing in brightness or contrast would differentially induce VIMS. The symptoms of VIMS should be most severe for the combination of high brightness and high contrast and conversely lowest for the low brightness and low contrast condition. Methods 33 healthy subjects were tested in a fixed-base flight simulator. Each subject flew in four consecutiv…

Arrival-time judgments on multiple-lane streets: the failure to ignore irrelevant traffic

How do road users decide whether or not they have enough time to cross a multiple-lane street with multiple approaching vehicles? Temporal judgments have been investigated for single cars approaching an intersection; however, close to nothing is known about how street crossing decisions are being made when several vehicles are simultaneously approaching in two adjacent lanes. This task is relatively common in urban environments. We report two simulator experiments in which drivers had to judge whether it would be safe to initiate street crossing in such cases. Matching traffic gaps (i.e., the temporal separation between two consecutive vehicles) were presented either with cars approaching o…

Interpersonal Distance Regulation and Approach-Avoidance Reactions Are Altered in Psychopathy

In this study, we examined the impact of psychopathy on approach-avoidance reactions and interpersonal distance (IPD) in response to social cues. We selected a student sample and measured psychopathy via self-report. Participants were immersed in a virtual environment in which a virtual person displayed either angry or happy facial expressions. In the first experiment, participants had to walk toward the virtual person until a comfortable IPD had been reached. In the second experiment, participants had to push or pull a joystick in response to the facial expression of the virtual person. Our results suggest that psychopathy does not change average IPD but does impair its regulation. That i…

The big picture: effects of surround on immersion and size perception.

Despite the fear of the entertainment industry that illegal downloads of films might ruin their business, going to the movies continues to be a popular leisure activity. One reason why people prefer to watch movies in cinemas may be the surround of the movie screen or its physically huge size. To disentangle the factors that might contribute to the size impression, we tested several measures of subjective size and immersion in different viewing environments. For this purpose we built a model cinema that provided visual angle information comparable with that of a real cinema. Subjects watched identical movie clips in a real cinema, a model cinema, and on a display monitor in isolation. Wher…

Wall patterns influence the perception of interior space

The texture of an object’s surface influences its perceived spatial extent. For example, Hermann von Helmholtz reported that a square patch with black and white stripes appears elongated perpendicular to the stripes’ orientation. This time-honoured finding stands in contrast with more recent recommendations by interior-design experts who suggest that stripe wall patterns make rooms appear elongated in the direction parallel to the stripes’ orientation. In a series of four experiments, we presented stripe wall patterns and varied the orientation of the stripes (horizontal vs. vertical) and their density (number of stripes per degree of visual angle). Subjects estimated the width and height …

Intra-visual conflict in visually induced motion sickness

Abstract Motion sickness (MS) can be a debilitating side-effect not just of sea travel, but also when immersed in video games or virtual environments (visually induced MS). To explore the impact of visual display parameters on motion sickness, we presented footage taken on an automobile race track to different groups of observers during three experiments. In Experiment 1, one group watched the movie wearing a head-mounted display (HMD) and a second group looked at a large projection screen with unrestricted view. Resolution and visual angle were equated. In contrast to common assumption, the projection screen produced significantly higher motion sickness scores than the HMD. To understand t…

The Mona Lisa effect: Neural correlates of centered and off-centered gaze

The Mona Lisa effect describes the phenomenon when the eyes of a portrait appear to look at the observer regardless of the observer's position. Recently, the metaphor of a cone of gaze has been proposed to describe the range of gaze directions within which a person feels looked at. The width of the gaze cone is about five degrees of visual angle to either side of a given gaze direction. We used functional magnetic resonance imaging to investigate how the brain regions involved in gaze direction discrimination would differ between centered and decentered presentation positions of a portrait exhibiting eye contact. Subjects observed a given portrait's eyes. By presenting portraits with varyin…

Effectiveness and user acceptance of infotainment-lockouts: A driving simulator study

Abstract Lockout is a system-initiated distraction mitigation strategy that renders certain features of in-vehicle information systems (IVISs) non operable while the vehicle is in motion. The aim of this driving simulator study was to examine the influence of lockouts on driving performance and user acceptance. Overall, 52 participants performed six tasks with fully unlocked, partially locked, and completely locked IVIS. Within a repeated-measures design, we assessed user acceptance. As participants were free to decide where to conduct a secondary task, we could only analyse driving performance of 26 drivers. After each driving section, the participants rated the respective system with resp…

Sensorimotor aspects of high-speed artificial gravity: I. Sensory conflict in vestibular adaptation

Short-radius centrifugation offers a promising and affordable countermeasure to the adverse effects of prolonged weightlessness. However, head movements made in a fast rotating environment elicit Coriolis effects, which seriously compromise sensory and motor processes. We found that participants can adapt to these Coriolis effects when exposed intermittently to high rotation rates and, at the same time, can maintain their perceptual-motor coordination in stationary environments. In this paper, we explore the role of inter-sensory conflict in this adaptation process. Different measures (vertical nystagmus, illusory body tilt, motion sickness) react differently to visual-vestibular conflict a…

The effect of body posture on long range time-to-contact estimation

On Earth, gravity accelerates freely moving objects downward, whereas upward-moving objects are being decelerated. Do humans take internalised knowledge of gravity into account when estimating time-to-contact (TTC, the time remaining before the moving object reaches the observer)? To answer this question, we created a motion-prediction task in which participants saw the initial part of an object's trajectory moving on a collision course prior to an occlusion. Observers had to judge when the object would make contact with them. The visual scene was presented with a head-mounted display. Participants lay either supine (looking up) or prone (looking down), suggestive of the ball either rising…

Effects of Visually Induced Motion Sickness on Emergency Braking Reaction Times in a Driving Simulator

Objective: The study explores associations of visually induced motion sickness (VIMS) with emergency braking reaction times (RTs) in driving simulator studies. It examines the effects over the progression of multiple simulated drives. Background: Driving simulator usage has many advantages for RT studies; however, if it induces VIMS, the observed driving behavior might deviate from real-world driving, potentially masking or skewing results. Possible effects of VIMS on RT have long been entertained, but the progression of VIMS across simulated drives has so far not been sufficiently considered. Method: Twenty-eight adults completed six drives on 2 days in a fixed-base driving simulator. At f…

Judging the contact-times of multiple objects: Evidence for asymmetric interference.

The accuracy of time-to-contact (TTC) judgments for single approaching objects is well researched, however, close to nothing is known about our ability to make simultaneous TTC judgments for two or more objects. Such complex judgments are required in many everyday situations, for instance when crossing a multi-lane street or when engaged in multi-player ball games. We used a prediction-motion paradigm in which participants simultaneously estimated the absolute TTC of two objects, and compared the performance to a standard single-object condition. Results showed that the order of arrival of the two objects determined the accuracy of the TTC estimates: Estimation of the first-arriving object …

Quantifying the Wollaston Illusion

In the early 19th century, William H. Wollaston impressed the Royal Society of London with engravings of portraits. He manipulated facial features, such as the nose, and thereby dramatically changed the perceived gaze direction, although the eye region with iris and eye socket had remained unaltered. This Wollaston illusion has been replicated numerous times but never with the original stimuli. We took the eyes (pupil and iris) from Wollaston’s most prominent engraving and measured their perceived gaze direction in an analog fashion. We then systematically added facial features (eye socket, eyebrows, nose, skull, and hair). These features had the power to divert perceived gaze direction by…

A new perspective on CMS – testing the effect of camera displacement in a realistic lane-change task

Convex rear view mirrors compromise distance and time-to-contact judgements

Convex rear view mirrors increasingly replace planar mirrors in automobiles. While increasing the field of view, convex mirrors are also taken to increase distance estimates and thereby reduce safety margins. However, this study failed to replicate systematic distance estimation errors in a real world setting. Whereas distance estimates were accurate on average, convex mirrors lead to significantly more variance in distance and spacing estimations. A second experiment explored the effect of mirrors on time-to-contact estimations, which had not been previously researched. Potential effects of display size were separated from effects caused by distortion in convex mirrors. Time-to-contact est…

Visually Induced Motion Sickness on the Horizon

Visually induced motion sickness is an unpleasant but common side-effect of many simulations and VR-applications. We investigated whether an earth-fixed reference frame provided in the simulation is able to reduce motion sickness. To do so, we created a moving starfield that did not contain any indicators of the spatial orientation of the observer. As the observer was simulated to move through the randomly oscillating starfield, a time-to-contact task had to be carried out. Two colored stars on collision course with each other had to be spotted, then they disappeared and the time of their collision had to be judged. Eye-movements, task performance, and motion sickness were recorded. This co…

Axis Rotation and Visually Induced Motion Sickness: The Role of Combined Roll, Pitch, and Yaw Motion

A well-known phenomenon in aviation and in virtual environments such as simulators or computer games is motion sickness (MS). The amount of sensory conflict is thought to be responsible for the severity of MS, which should increase with the complexity of the simulated motion. The focus of the present study is on the direction and complexity of simulated body rotations in the genesis and severity of visually induced MS. The methods utilized for this study are as follows: Three simulated rollercoaster rides including translational movement in the fore-aft axis and additional rotational motion either in pitch only, along the pitch and roll axes, or in pitch, roll, and yaw were generated. The a…

Cross-ethnic assessment of body weight and height on the basis of faces

Abstract Previous research has revealed a strong relationship between mere visual facial cues and body weight. They can be exploited to validly judge the weight of the human body. We tested to what extent observers are able to judge body weight and height on the basis of same-ethnicity and different-ethnicity faces. Caucasian and Asian observers saw Caucasian and Asian faces and estimated the person’s weight and height – merely on the basis of greyscale photographs of the face. These height and weight estimates were influenced by ethnocentric specifics of familiar face proportion and face–body relationship. Own-ethnicity weight estimations showed higher accuracy than foreign-ethnicity estim…

Body image avoidance affects interpersonal distance perception: A virtual environment experiment.

OBJECTIVE Eating disorders have a considerable influence on social contacts. The avoidance towards the own body may result in the avoidance of others. Previous research has found a preference for larger interaction distances in individuals with eating disorders (ED) as compared to control participants (CG). We aimed to replicate these findings and to investigate whether the body weight of the interactant moderates the effect. METHOD We recruited a female sample with mixed ED subtypes (n = 21) and a female CG (n = 28). Participants were immersed in a virtual environment and engaged in a number of fictitious social interactions. They approached a virtual person until a comfortable distance fo…

The Auditory Kuleshov Effect: Multisensory Integration in Movie Editing

Almost a hundred years ago, the Russian filmmaker Lev Kuleshov conducted his now famous editing experiment in which different objects were added to a given film scene featuring a neutral face. It is said that the audience interpreted the unchanged facial expression as a function of the added object (e.g., an added soup made the face express hunger). This interaction effect has been dubbed “Kuleshov effect.” In the current study, we explored the role of sound in the evaluation of facial expressions in films. Thirty participants watched different clips of faces that were intercut with neutral scenes, featuring either happy music, sad music, or no music at all. This was crossed with the facia…

The widening of the gaze cone in patients with social anxiety disorder and its normalization after CBT

Gaze plays a crucial role in social interactions. Social Anxiety Disorder (SAD), which is associated with severe impairment of social interactions, is thus likely to exhibit disturbances of gaze perception. We conducted two experiments with SAD-patients and healthy control participants using a virtual head whose gaze could be interactively manipulated. We determined the subjective area of mutual gaze, the so-called gaze cone, and measured it prior to and after a psychotherapeutic intervention (Exp. 1). Patients exhibited larger gaze cones than control subjects. Exp. 2 varied the emotional expression of the virtual head. These data were validated using a real person (professional actor) as s…

The effect of furnishing on perceived spatial dimensions and spaciousness of interior space

Despite the ubiquity of interior space design, there is virtually no scientific research on the influence of furnishing on the perception of interior space. We conducted two experiments in which observers were asked to estimate the spatial dimensions (size of the room dimensions in meters and centimeters) and to judge subjective spaciousness of various rooms. Experiment 1 used true-to-scale model rooms with a square surface area. Furnishing affected both the perceived height and the spaciousness judgments. The furnished room was perceived as higher but less spacious. In Experiment 2, rooms with different square surface areas and constant physical height were presented in virtual reality. Fu…

Public acceptance of semi-automated truck platoon driving. A comparison between Germany and California

Abstract Platooning technology aims at achieving fuel savings by reducing the distance between two or more electronically coupled vehicles. This technology has recently been tested on public highways with heavy trucks in Germany and California. The objective of this study is to assess the level of acceptance among other road users as well as influencing factors of acceptance. An online questionnaire was administered in Germany and California with a total of N = 536 participants. They received information about truck platoon driving (level-1 and level-2 automation) and answered questions about their attitudes towards the technology as well as their behavioral intention to cooperate with the …

The anisotropy of personal space.

Violations of personal space are associated with discomfort. However, the exact function linking the magnitude of discomfort to interpersonal distance has not yet been specified. In this study, we explore whether interpersonal distance and discomfort are isotropic with respect to uncomfortably far or close distances. We also extend previous findings with regard to intrusions into personal space as well as maintenance of distances outside of personal space. We presented subjects with 15 interpersonal distances ranging from 40 to 250 cm and obtained verbal and joystick-based ratings of discomfort. Whereas discomfort rose immediately when personal space was entered, the gradient was less steep…

Logik I: Einführung in die Logik

Wir haben in ▶ Abschn. 1.1 und ▶ Abschn. 1.2 festgestellt, dass die Psychologie Aussagen uber Seelisches macht. Wir haben auch versucht, den Seelenbegriff zu klaren. Jetzt gilt es zu klaren, was Aussagen sind. Ganz einerlei, ob wir Psychologie in erster Linie als Wissenschaft vom Verhalten verstehen oder geneigt sind, die Ruhrungen der Seele etwas philosophischer aufzufassen, um die Frage nach der Aussage kommen wir nicht herum. Sie ist fundamental, ja so fundamental, dass Sie sich vielleicht fragen, ob diese Grundlichkeit notwendig sei. Sie ist es, wenn wir in irgendeiner Form das bewerten wollen, was unsere Forschung herausgebracht hat. Und genau das ist ja die Aufgabe des Wissenschaftler…

Fashion versus perception: the impact of surface lightness on the perceived dimensions of interior space.

Objectives: We compare expert opinion with perceptual judgment regarding the influence of color on the perceived height and width of interior rooms. Background: We hypothesize that contrary to popular belief, ceiling and wall lightness have additive effects on perceived height, whereas the lightness contrast between these surfaces is less important. We assessed the intuitions of architectural experts as to which surface colors maximize apparent height and compared these intuitions with psychophysical height and width estimates for rooms differing in ceiling, floor, and wall lightness. Method: Experiment 1 was a survey of architectural experts and nonexperts. Experiments 2 and 3 presented v…

Phänomenologie und Gestaltpsychologie

Die fur die deutsche Psychologie wohl wichtigste Geistesbewegung ist die Phanomenologie, die Lehre der Erscheinungen. Wir sind uns unserer Sinneserfahrungen und Gedanken bewusst, aber wie dies geschieht, wird im 19. Jahrhundert auf dem europaischen Kontinent – vielleicht gefordert durch die Ubung in Naturbetrachtung und dem Versuch, objektive Beobachtungen anzustellen – allmahlich in ganz neuem Lichte gesehen. Descartes hatte noch angenommen, dass Bewusstsein als zentrale Instanz alles Denken und Erleben begleitet, wenn nicht ermoglicht, und hatte darin kein Problem gesehen. Wenn man aber das Bewusstsein – sei es eines Sinneseindrucks, sei es des „cogito“ – auch wieder als Erscheinung auffa…

Supplementary Material - Supplemental material for The Ups and Downs of Camera-Monitor Systems: The Effect of Camera Position on Rearward Distance Perception

Supplemental material, Supplementary Material, for The Ups and Downs of Camera-Monitor Systems: The Effect of Camera Position on Rearward Distance Perception by Christoph Bernhard and Heiko Hecht in Human Factors: The Journal of Human Factors and Ergonomics Society

Testing the egocentric mirror-rotation hypothesis.

AbstractAlthough observers know about the law of reflection, their intuitive understanding of spatial locations in mirrors is often erroneous. Hecht et al. (2005) proposed a two-stage mirror-rotation hypothesis to explain these misconceptions. The hypothesis involves an egocentric bias to the effect that observers behave as if the mirror surface were rotated by about 2° to be more orthogonal than is the case. We test four variants of the hypothesis, which differ depending on whether the virtual world, the mirror, or both are taken to be rotated. We devised an experimental setup that allowed us to distinguish between these variants. Our results confirm that the virtual world — and only the v…

Differentiating the differential rotation effect.

As an observer views a picture from different viewing angles, objects in the picture appear to maintain their orientation relative to the observer. For instance, the eyes of a portrait appear to follow the observer as he or she views the image from different angles. We have explored this rotation effect, often called the Mona Lisa effect. We report three experiments that used portrait photographs to test variations of the Mona Lisa effect. The first experiment introduced picture displacements relative to the observer in directions beyond the horizontal plane. The Mona Lisa effect remained robust for vertical and/or diagonal observer displacements. The experiment also included conditions in …

Measuring Perceived Ceiling Height in a Visual Comparison Task

When judging interior space, a dark ceiling is judged to be lower than a light ceiling. The method of metric judgments (e.g., on a centimetre scale) that has typically been used in such tasks may reflect a genuine perceptual effect or it may reflect a cognitively mediated impression. We employed a height-matching method in which perceived ceiling height had to be matched with an adjustable pillar, thus obtaining psychometric functions that allowed for an estimation of the point of subjective equality (PSE) and the difference limen (DL). The height-matching method developed in this paper allows for a direct visual match and does not require metric judgment. It has the added advantage of pro…

The cone of gaze

Gaze direction is an important cue that regulates social interactions. Although humans are very accurate in determining gaze directions in general, they have a surprisingly liberal criterion for the presence of mutual gaze. We first established a psychophysical task to measure the cone of gaze, which required observers to adjust the eyes of a virtual head to the margins of the area of mutual gaze. Then we examined differences between 2D, 3D, and genuine real life gaze. Finally, the tolerance for image distortions when the virtual head is not viewed from the proper vantage point was investigated. Gaze direction was remarkably robust toward loss in detail and distortion. Important lessons for…

Logik II: Logik als formalisierte Sprache

In ▶ Kap. 2haben wir erfahren, was ein Argument ist. Man kann ein Argument als Begrundungssystem verstehen, das aus mehreren Satzen besteht, namlich aus einer begrundenden Pramisse und einer begrundeten Konklusion . Jetzt wollen wir die Frage weiterverfolgen, wann ein Argument wahr ist.

AMBIENT LIGHTING MODIFIES THE FLAVOR OF WINE

It is well known that the color of a beverage can influence its flavor. We conducted three experiments to investigate the effect of the ambient room color on flavor, while leaving the color of the beverage unaltered. We chose white wine as the beverage and used several methods to fully explore the potential role of ambient light. First, a group of wine buyers made judgments on flavor and global liking while tasting a Riesling on site at a local winery. Ambient color influenced the subjective value of the wine. Wine tasted better in blue or red environments as compared with green and white. A second group was tested in the laboratory. Ambient color modified the taste, but not the odor of the…

Psychopathy and the Regulation of Interpersonal Distance

Psychopathic traits are often associated with interpersonal and affective deficits. This study examined the impact of psychopathy on judgments of comfortable egocentric interpersonal distance (Experiment 1) and exocentric interpersonal distance (Experiment 2). We selected a student sample and measured psychopathy via self-report. To study spatial behavior under highly controlled conditions, these participants were immersed in a virtual environment. In Experiment 1, they approached a virtual person with angry or happy facial expression until a comfortable distance for conversation was reached. In Experiment 2, participants adjusted a comfortable distance between two avatars. Our results sug…

Can We Study Autonomous Driving Comfort in Moving-Base Driving Simulators? A Validation Study.

Objective: To lay the basis of studying autonomous driving comfort using driving simulators, we assessed the behavioral validity of two moving-base simulator configurations by contrasting them with a test-track setting. Background: With increasing level of automation, driving comfort becomes increasingly important. Simulators provide a safe environment to study perceived comfort in autonomous driving. To date, however, no studies were conducted in relation to comfort in autonomous driving to determine the extent to which results from simulator studies can be transferred to on-road driving conditions. Method: Participants ( N = 72) experienced six differently parameterized lane-change and de…

Validating an Efficient Method to Quantify Motion Sickness

Objective: Motion sickness (MS) can be a debilitating side effect associated with motion in real or virtual environments. We analyzed the effect of expectancy on MS and propose and validate a fast and simple MS measure.Background: Several questionnaires measure MS before or after stimulus presentation, but no satisfactory tool has been established to quickly capture MS data during exposure. To fill this gap, we introduce the Fast MS Scale (FMS), a verbal rating scale ranging from zero (no sickness at all) to 20 (frank sickness). Also, little is known about the role of expectancy effects in MS studies. We conducted an experiment that addressed this issue.Method: For this study, 126 volunteer…

Crossing a Multi-Lane Street: Irrelevant Cars Increase Unsafe Behavior

Before crossing a road or an intersection, road users have to determine among the surrounding traffic whether or not they have enough time to safely complete their maneuver. Temporal judgments have been investigated for single cars approaching an intersection, however, close to nothing is known about how street-crossing decisions are being made when several vehicles are simultaneously approaching in two adjacent lanes. We conducted a simulator experiment in which observers indicated whether or not they had enough time to complete safe street crossing. Traffic gaps were presented either with a single or two oncoming cars on different lanes, in such a way that in all cases, only the shortest …

Surface Lightness Influences Perceived Room Height

Surprisingly little scientific research has been conducted on the effects of colour and lightness on the perception of spaciousness. Practitioners and architects typically suggest that a room's ceiling appears higher when it is painted lighter than the walls, while darker ceilings appear lower. Employing a virtual reality setting, we studied the effects of the lightness of different room surfaces on perceived height in two psychophysical experiments. Observers judged the height of rooms varying in physical height as well as in the lightness of ceiling, floor, and walls. Experiment 1 showed the expected increase of perceived height with increases in ceiling lightness. Unexpectedly, the perce…

The limits of visual mass perception

The theory of direct perception suggests that observers can accurately judge the mass of a box picked up by a lifter shown in a point-light display. However, accurate perceptual performance may be limited to specific circumstances. The purpose of the present study was to systematically examine the factors that determine perception of mass, including display type, lifting speed, response type, and lifter's strength. In contrast to previous research, a wider range of viewing manipulations of point-light display conditions was investigated. In Experiment 1, we first created a circumstance where observers could accurately judge lifts of five box masses performed by a lifter of average strength…

The Event Structure of Motion Perception

Motion perception on the basis of optic flow is often studied using purely perceptual response paradigms such as forced choice preferences, and using straightforward motor responses such as simple stereotypical reaction times. Here we argue for a more complex perspective that takes into account the event structure of ecological motion perception. In particular, we hope to convince the reader that the would-be perceptual response to a motion stimulus is noticeably modified be the type of response that is required from the actor. We will argue that our actions modify our perception and more precisely, that the planning component of intended actions influence processing of time critical motion…

How facial masks alter the interaction of gaze direction, head orientation, and emotion recognition

The COVID-19 pandemic has altered the way we interact with each other: mandatory mask-wearing obscures facial information that is crucial for emotion recognition. Whereas the influence of wearing a mask on emotion recognition has been repeatedly investigated, little is known about the impact on interaction effects among emotional signals and other social signals. Therefore, the current study sought to explore how gaze direction, head orientation, and emotional expression interact with respect to emotion perception, and how these interactions are altered by wearing a face mask. In two online experiments, we presented face stimuli from the Radboud Faces Database displaying different facial ex…

A Case for Raising the Camera: A Driving Simulator Test of Camera-Monitor Systems

Objective This experiment provides a first-of-its-kind driving-simulator study to investigate the feasibility of camera-monitor systems (CMS) with displaced side-mounted cameras in sedans. Background Among the increasing number of studies investigating the replacement of side-mounted rearview mirrors with CMS, the placement of side-mounted cameras has been largely neglected. Moreover, user preferences with respect to camera placement have not been validated in a driving simulator. Past research merely has shown that the vertical camera position can affect distance perception. Method In a driving simulator experiment, we investigated the effects of rearward camera placement on driver accepta…

Which Attribute of Ceiling Color Influences Perceived Room Height?

Objective:We investigate effects of the hue, saturation, and luminance of ceiling color on the perceived height of interior spaces.Background:Previous studies have reported that the perceived height of an interior space is influenced by the luminance of the ceiling, but not by the luminance contrast between ceiling and walls: brighter ceilings appeared higher than darker ceilings, irrespective of wall and floor luminance. However, these studies used solely achromatic colors. We report an experiment in which we extend these findings to effects of chromatic ceiling colors.Methods:We presented stereoscopic room simulations on a head-mounted display (Oculus Rift DK2) and varied hue (red, green,…

User acceptance of automated public transport

Abstract Autonomous driving is receiving increasing attention in the automotive industry as well as in public transport. However, it is still unclear whether users are willing to use automated public transportation at all. In order to answer this and other questions, the transport company of the city of Mainz, Germany, tested the autonomous minibus EMMA (Elektro-Mobilitat Mainz Autonom) on a 600-meter-long test track in public space. The study presented here was conducted with the aim of exploring crucial determinants for the use of an autonomous minibus. On the basis of established acceptance models, a questionnaire was developed, which was completed in a field survey by a total of 942 par…

Stereoscopic Viewing Enhances Visually Induced Motion Sickness but Sound Does Not

Optic flow in visual displays or virtual environments often induces motion sickness (MS). We conducted two studies to analyze the effects of stereopsis, background sound, and realism (video vs. simulation) on the severity of MS and related feelings of immersion and vection. In Experiment 1, 79 participants watched either a 15-min-long video clip taken during a real roller coaster ride, or a precise simulation of the same ride. Additionally, half of the participants watched the movie in 2D, and the other half in 3D. MS was measured using the Simulator Sickness Questionnaire (SSQ) and the Fast Motion Sickness Scale (FMS). Results showed a significant interaction for both variables, indicatin…

The best way to assess visually induced motion sickness in a fixed-base driving simulator

Abstract Objective Driving simulator usage is becoming more widespread, yet many users still experience substantial motion sickness-like symptoms induced by optical flow, called visually induced motion sickness (VIMS). The Fast Motion sickness Scale (FMS) allows for continuous on-line assessment of VIMS. Using mixed models for ordinal data, this study investigated how to optimally analyze FMS data, and then used the resulting models to examine the development of symptoms over time in detail. Additionally, the study explored the impact of specific VIMS-inducing road elements. Methods Twenty-eight healthy young adults without prior simulator experience completed six courses on two days in a f…

Von Aristoteles bis zum 19. Jahrhundert

Nachdem wir einiges uber Logik und Wissenschaftstheorie gelernt haben, sind wir nun dazu in der Lage, die historischen Stromungen und Paradigmen in der Psychologie zu bewerten und einzuordnen. Dies kann und soll nur schlaglichtartig geschehen, da in dem vorliegenden Buch keine umfassende Geschichte der Psychologie nacherzahlt werden kann. Hierzu sei auf das problemgeschichtliche Werk von Ludwig Pongratz (1984) verwiesen. Wir wollen unsere „Schlaglichtgala“ mit einigen Beispielen aus der Antike sowie ein paar Brockchen aus dem Mittelalter und der Neuzeit bis ins 19. Jahrhundert fuhren, in dem die Psychologie als Wissenschaft im heutigen Sinn entstand.

Threshold-based vestibular adaptation to cross-coupled canal stimulation

Prior experiments have demonstrated that people are able to adapt to cross-coupled accelerations associated with head movements while spinning at high rotation rates (e.g., 23 rpm or 138°/s). However, while adapting, subjects commonly experience serious side effects, such as motion sickness, non-compensatory eye movements, and strong and potentially disorienting illusory body tilt or tumbling sensations. In the present study, we investigated the feasibility of adaptation using a threshold-based method, which ensured that the illusory tilt sensations remained imperceptible or just barely noticeable. This was achieved by incrementally increasing the angular velocity of the horizontal centrifu…

Wider is better but sharper is not: optimizing the image of camera-monitor systems

The replacement of rear-view mirrors with camera-monitor systems introduces new opportunities for design, such as altering the image quality and the rearward field-of-view. We investigated how the image quality and field-of-view might affect the distance and time-to-contact estimation of other vehicles. Eighty-six subjects estimated either their egocentric distance to a stationary vehicle (Experiment I) or the time-to-contact to an approaching vehicle (Experiment II). Throughout the experiments, the pixel density and either the field-of-view or the viewing condition varied. A larger field-of-view increased distance estimation accuracy and confidence. Reduced pixel density led to larger esti…

Do happy faces really modulate liking for Jackson Pollock art and statistical fractal noise images?

Flexas et al. (2013) demonstrated that happy faces increase preference for abstract art if seen in short succession. We could not replicate their findings. In our first experiment, we tested whether valence, saliency or arousal of facial primes can modulate liking of Jackson Pollock art crops. In the second experiment, the emphasis was on testing another type of abstract visual stimuli which possess similar low-level image features: statistical fractal noise images. Pollock crops were rated significantly higher when primed with happy faces in contrast to neutral faces, but not differently to the no-prime condition. Findings of our study suggest that affective priming with happy faces may be…

Vestibular adaptation to centrifugation does not transfer across planes of head rotation

Out-of-plane head movements performed during fast rotation produce non-compensatory nystagmus, sensations of illusory motion, and often motion sickness. Adaptation to this cross-coupled Coriolis stimulus has previously been demonstrated for head turns made in the yaw (transverse) plane of motion, during supine head-on-axis rotation. An open question, however, is if adaptation to head movements in one plane of motion transfers to head movements performed in a new, unpracticed plane of motion. Evidence of transfer would imply the brain builds up a generalized model of the vestibular sensory-motor system, instead of learning a variety of individual input/output relations separately. To investi…

Temporal-range estimation of multiple objects: evidence for an early bottleneck.

When making parallel time-to-contact (TTC) estimates of two approaching objects, the two respective TTC estimates interfere with one another in an asymmetric fashion. The TTC of the later-arriving object is systematically overestimated, while the estimated TTC for the first-arriving object is as accurate as in a condition presenting only a single object. This asymmetric interference points to a processing bottleneck that could be due to early (e.g., during the estimation of the TTC from the optic flow) or late (e.g., during the timing of the response or the motor execution) constraints in the TTC estimation process. We used a Sperling-like prediction-motion task to differentiate between the…

Pleasant music as a countermeasure against visually induced motion sickness.

Visually induced motion sickness (VIMS) is a well-known side-effect in virtual environments or simulators. However, effective behavioral countermeasures against VIMS are still sparse. In this study, we tested whether music can reduce the severity of VIMS. Ninety-three volunteers were immersed in an approximately 14-minute-long video taken during a bicycle ride. Participants were randomly assigned to one of four experimental groups, either including relaxing music, neutral music, stressful music, or no music. Sickness scores were collected using the Fast Motion Sickness Scale and the Simulator Sickness Questionnaire. Results showed an overall trend for relaxing music to reduce the severity o…

The behavioral validity of dual-task driving performance in fixed and moving base driving simulators

Abstract Next generation automotive hardware and user interfaces are increasingly pre-tested in driving simulators. What are the potential limitations of such simulations? We determined the relative and absolute validity of five different driving simulators at the Daimler AG by evaluating five functions of an in-vehicle system based on the guideline of the Alliance of Automobile Manufacturers (2006). The simulations were compared to on-road driving. We hypothesized that not only simulator characteristics, but also user characteristics, such as simulator sickness, gender, or age, influence behavioral validity. Even though relating simulator characteristics and user characteristics to driving…

Rationalismus und Empirismus

Weder die blose Hand noch der sich selbst uberlassene Verstand bringen viel zustande; es sind Instrumente und Hilfsmittel, durch die etwas zustande gebracht wird; der Verstand bedarf ihrer nicht minder als die Hand. Und wie die Instrumente der Hand die Bewegung entweder lenken oder leiten, so unterstutzen oder schutzen die Instrumente des Geistes den Verstand. (Francis Bacon, 1990)

Effects of distance and eye-height on time-to-contact estimates

Les effets de la distance et du point-de-vue sur le jugement du temps de pre-contact Lors de la realisation d’estimations du temps de pre-contact (time-to-contact TTC), les observateurs utilisent parfois des informations erronees dans leurs jugements, privilegiant la rapidite de decision et d’action au detriment de la precision. Dans ce contexte, nous avons etudie le role de la position de l’observateur par rapport a l’approche du mobile. Cinq experiences ont testees les effets de la distance et de la hauteur des yeux de l’observateur. Le sol pouvait avoir une texture reguliere, irreguliere ou absente. En controlant le temps de visibilite, le TTC et la vitesse du mobile, nous avons evite de…

Having a Drink with Tchaikovsky: The Crossmodal Influence of Background Music on the Taste of Beverages.

Abstract Previous research has shown that auditory cues can influence the flavor of food and drink. For instance, wine tastes better when preferred music is played. We have investigated whether a music background can modify judgments of the specific flavor pattern of a beverage, as opposed to mere preference. This was indeed the case. We explored the nature of this crosstalk between auditory and gustatory perception, and hypothesized that the ‘flavor’ of the background music carries over to the perceived flavor (i.e., descriptive and evaluative aspects) of beverages. First, we collected ratings of the subjective flavor of different music pieces. Then we used a between-subjects design to cro…

Driver Situation Awareness and Perceived Sleepiness during Truck Platoon Driving–Insights from Eye-tracking Data

Truck platoon driving technology uses vehicle-to-vehicle communication to allow one truck to follow another in an automated fashion. The first vehicle is operated manually, the second vehicle is dr...

Genre-dependent effects of 3D film on presence, motion sickness, and protagonist perception

Do the increasingly popular 3D movies change how we perceive the content of the movie? We presented short (3.21 min) film sequences to observers equipped with shutter glasses. Three genres (horror, action, and documentary) were crossed with three between-subjects viewing conditions (director’s 3D, artificial 3D, and 2D). Observers had to rate how the film impressed them in terms of arousal, motion sickness, presence, and immersion. They also judged the personality, attractiveness, and intelligence of the protagonist in all viewing conditions. Not surprisingly, horror films produced more arousal and presence than action films. Documentaries scored lowest on presence. Action movies produced t…

The Mona Lisa effect: Testing the limits of perceptual robustness vis-à-vis slanted images

We report three experiments that test the limits of the Mona Lisa effect. The gaze of a portrait that is looking at us appears to follow us around as we move with respect to the picture. Even if our position is shifted considerably to the side, or if the picture is severely slanted, do we feel the gaze to be directed at us? We determined the threshold where this effect breaks down to be maximally 70? of picture slant relative to the observer. Different factors modulate this remarkable robustness, among them being the display medium and the nature of the picture. The threshold was considerably lower when the picture was mounted on a physical surface as opposed to a computer simulation of sla…

The Ups and Downs of Camera-Monitor Systems: The Effect of Camera Position on Rearward Distance Perception

Objective This study investigates the effects of different positions of side-mounted rear-view cameras on distance estimation of drivers. Background Camera-monitor systems bring advantages as compared to conventional rear-view mirrors, such as improved aerodynamics and enlarged field-of-view. Applied research has mainly focused on the comparison between cameras and mirrors or on positioning of in-vehicle monitors. However, the positioning of the exterior camera awaits investigation given that the perspective of the observer at does affect depth perception at large. Method In two experiments, a total of 50 students estimated metric distances to static vehicles presented in realistic or 3D-re…

Inverting the Wollaston Illusion: Gaze Direction Attracts Perceived Head Orientation

In the early 19th century, William H. Wollaston impressed the Royal Society of London with engravings of portraits. He manipulated facial features, such as the nose, and thereby dramatically changed the perceived gaze direction, although the eye region with iris and eye socket had remained unaltered. This Wollaston illusion can be thought of as head orientation attracting perceived gaze direction when the eye region is unchanged. In naturalistic viewing, the eye region changes with head orientation and typically produces a repulsion effect. Here we explore if there is a flip side to the illusion. Does the gaze direction also alter the perceived direction of the head? We used copies of the o…

Judging body weight from faces: the height-weight illusion.

Being able to exploit features of the human face to predict health and fitness can serve as an evolutionary advantage. Surface features such as facial symmetry, averageness, and skin colour are known to influence attractiveness. We sought to determine whether observers are able to extract more complex features, namely body weight. If possible, it could be used as a predictor for health and fitness. For instance, facial adiposity could be taken to indicate a cardiovascular challenge or proneness to infections. Observers seem to be able to glean body weight information from frontal views of a face. Is weight estimation robust across different viewing angles? We showed that participants stron…

Who is looking at me? The cone of gaze widens in social phobia

Gaze direction is an important cue that regulates social interactions and facilitates joint attention. Although humans are very accurate in determining gaze directions in general, they have a surprisingly liberal criterion for the presence of mutual gaze. Using an established psychophysical task that required observers to adjust the eyes of a virtual head to the margins of the area of mutual gaze, we examined whether the resulting cone of gaze is altered in people with social phobia. It turned out that during presence of a second virtual person, the gaze cone's width was specifically enlarged in patients with social phobia as compared to healthy controls. The size of this effect was correla…

Cognitive performance and emotion are indifferent to ambient color

Folklore has it that ambient color has the power to relax or arouse the observer and enhance performance when executing cognitive tasks. We picked a number of commercially available colors that allegedly have the power to alter cognitive performance and the emotional state, and exposed subjects to them while solving a battery of cognitive tasks. The colors were “Cool Down Pink”, which is said to produce relaxing effects and reduce effort, “Energy Red”, allegedly enhancing performance via increased arousal, “Relaxing Blue”, which is said to enhance attention and concentration, as well as white as a control. In a between-subjects design, a total of 170 high school students carried out five ta…

The shape of personal space.

The notion of a personal space surrounding one's ego-center is time-honored. However, few attempts have been made to measure the shape of this space. With increasing use of virtual environments, the question has arisen if real-world aspects, such as gender-effects or the shape of personal space, translate to virtual setups. We conducted two experiments, one with real people matched according to body height and level of acquaintance in a large laboratory setting, and one where subjects faced a virtual character, likewise matched to their body height. The first experiment also used a mannequin in place of the second human observer. The second experiment additionally manipulated the perspectiv…