Consistent haptic feedback is required but it is not enough for natural reaching to virtual cylinders

In virtual reality it is easy to control the visual cues that tell us about an object's shape. However, it is much harder to provide realistic virtual haptic feedback when grasping virtual objects. In this study we examined the role of haptic feedback when grasping (virtual) cylinders with an elliptical circumference. In Experiment 1 we placed the same circular cylinder at the simulated location of virtual elliptical cylinders of varying shape, so that the haptic feedback did not change when the visually specified shape changed. We found that the scaling of maximum grip aperture with the diameter of the nearest principal axis (.14+/-.04) was much weaker than when grasping real cylinders (.54+/-.04, Cuijpers, Brenner, & Smeets, 2006 Grasping reveals visual misjudgements of shape. Experimental Brain Research, 175, 32-44). For the scaling of grip orientation with the orientation of the cylinder we found large individual differences: the range is .07-.82 (average .42+/-.07) as compared to .55-.79 (average .67+/-.03) for grasping real cylinders. In Experiment 2 we provided consistent haptic feedback by placing real cylinders that matched the location, shape and orientation of the virtual cylinders. The scaling gains of both maximum grip aperture (.39+/-.04) and grip orientation (.56+/-.08) were substantially higher than in Experiment 1, but still lower than for grasps to real cylinders. The variability between participants for the scaling of grip orientation was also much reduced. These results showed that although haptic feedback must be consistent with visual information, it is not sufficient for natural prehension. We discuss the implications of these findings in terms of the integration of visual information with haptic feedback.     

The personality basis of justice: The five‐factor model as an integrative model of personality and procedural fairness effects on cooperation

Building upon the self‐based model of cooperation (De Cremer & Tyler, 2005 ), the present study investigates the relationship between the five‐factor model (FFM) and cooperation. Study 1 (N = 56), an experiment conducted in the laboratory, and Study 2 (N = 116), a field study conducted in an organisational context, yielded a moderator effect between neuroticism and procedural fairness in explaining cooperation. Study 3 (N = 177) showed that this moderator effect was mediated by the self‐uncertainty and relational variables proposed by the self‐based model of cooperation. It is concluded that the FFM is useful in explaining cooperation and contributes to a better understanding of (procedural) fairness effects. Moreover, the necessity to build integrative, multi‐level models that combine core and surface aspects of personality to explain the effects of fairness on cooperation is elaborated upon. Copyright © 2008 John Wiley & Sons, Ltd.     

“Seeing is believing”: The effects of facial expressions of emotion and verbal communication in social dilemmas

In social dilemmas, verbal communication of one's intentions is an important factor in increasing cooperation. In addition to verbal communication of one's intentions, also the communication of emotions of anger and happiness can influence cooperative behavior. In the present paper, we argue that facial expressions of emotion moderate verbal communication in social dilemmas. More specifically, three experiments showed that if the other person displayed happiness he or she was perceived as honest, trustworthy, and reliable, and cooperation was increased when verbal communication was cooperative rather than self‐interested. However, if the other person displayed anger, verbal communication did not influence people's decision behavior. Results also showed interactive effects on people's perceptions of trustworthiness, which partially mediated decision behavior. These findings suggest that emotion displays have an important function in organizational settings because they are able to influence social interactions and cooperative behavior. Copyright © 2009 John Wiley & Sons, Ltd.     

Training self‐assessment and task‐selection skills to foster self‐regulated learning: Do trained skills transfer across domains?

Students' ability to accurately self‐assess their performance and select a suitable subsequent learning task in response is imperative for effective self‐regulated learning. Video modeling examples have proven effective for training self‐assessment and task‐selection skills, and—importantly—such training fostered self‐regulated learning outcomes. It is unclear, however, whether trained skills would transfer across domains. We investigated whether skills acquired from training with either a specific, algorithmic task‐selection rule or a more general heuristic task‐selection rule in biology would transfer to self‐regulated learning in math. A manipulation check performed after the training confirmed that both algorithmic and heuristic training improved task‐selection skills on the biology problems compared with the control condition. However, we found no evidence that students subsequently applied the acquired skills during self‐regulated learning in math. Future research should investigate how to support transfer of task‐selection skills across domains.     

Psychological essentialism and the differential attribution of uniquely human emotions to ingroups and outgroups

According to the psychological essentialism perspective, people tend to explain differences between groups by attributing them different essences. Given a pervasive ethnocentrism, this tendency implies that the human essence will be restricted to the ingroup whereas outgroups will receive a lesser degree of humanity. Therefore, it is argued that people attribute more uniquely human characteristics to the ingroup than to the outgroup. The present article focuses on secondary emotions that constitute such characteristics. Study 1 showed that members of high‐ and low‐status groups attribute more positive secondary emotions to the ingroup than to the outgroup. Study 2 verified that the differential attribution extended also to negative secondary emotions. No exemplars of emotions were provided in Study 3. Instead, participants had to estimate the means of two distributions of numbers that supposedly represented characteristics of the ingroup and of the outgroup. The results of this third experiment illustrated the reluctance to attribute secondary emotions to the outgroup. The findings are discussed from the perspective of psychological essentialism. Copyright © 2001 John Wiley & Sons, Ltd.     

Testing the counter model for perceptual identification: Effects of repetition priming and word frequency

The counter model for perceptual identification (Ratcliff & McKoon, 1997) differs from alternative views of word recognition in two important ways. First, it assumes that prior study of a word does not result in increased sensitivity but, rather, in bias. Second, the effects of word frequency and prior study are explained by different mechanisms. In the present experiment, study status and word frequency of target and foil were varied independently. Using a forced-choice task, we replicated the bias effect. However, we also found several interactions between frequency and prior study that are in direct conflict with the counter model. Most important, prior study of both alternatives resulted in an attenuation of the frequency effect and an increase in performance for low-frequency targets, but not for high-frequency targets. These findings suggest that the effects of frequency and prior study are not mediated by completely independent mechanisms.     

The effect of expectation on the identification of known and unknown persons

In this experiment we investigated the influence of expectation, exposure time and jacket hood positioning on person identification. Thirty subjects, all employees of the TNO Institute for Perception, participated in the experiment. They were presented with slides showing known and unknown persons who were photographed under bad lighting conditions. Limited viewing conditions considerably deteriorated subjects' performance and under these circumstances all experimental manipulations significantly affected identification accuracy. Contrary to what was expected longer exposure times impaired performance. The results are discussed in light of recent research on face recognition (Bruce and Young, 1986; Read, Vokey, and Hammersley, 1990).     

Holding an object one is looking at: Kinesthetic information on the object’s distance does not improve visual judgments of its size

Visual judgments of distance are often inaccurate. Nevertheless, information on distance must be procured if retinal image size is to be used to judge an object’s dimensions. In the present study, we examined whether kinesthetic information about an object’s distance—based on the posture of the arm and hand when holding it—influences the object’s perceived size. Subjects were presented with a computer simulation of a cube. This cube’s position was coupled to that of a rod in the subject’s hand. Its size was varied between presentations. Subjects had to judge whether the cube they saw was larger than, smaller than, or the same size as a reference. On some presentations, a small difference was introduced between the positions of the rod and of the simulated cube. When the simulated cube was slightly closer than the rod, subjects judged the cube to be larger. When it was farther away, they judged it to be smaller. We show that these changes in perceived size are due to alterations in the cube’s distance from the subject rather than to kinesthetic information.