Quantification of swim patterns in the morris water maze

Spatial learning and memory in rodents is most often assessed in the Morris water maze. Neurobiologists have to distinguish behavioral patterns to unravel underlying neuronal systems. We analyzed swim patterns of mice videotaped before and after training with a multitrial procedure in the water maze. In addition to traditional parameters, the animals’ position in relation to trained and other possible platform locations was estimated five times per second by an image analysis system. This parameter,cumulative distance to platform, was correlated with time spent in the platform quadrant but not with latency to and crossings of the platform location. We detected a subgroup of animals with concentric patterns within the group of spatial/persistent patterns. Random patterns were classified as well. Swim patterns before training were not predictive for the one after training. In summary, image analysis systems have made it very convenient to quantify behavior. Using their capacity, we have further improved the analysis of swim patterns, revealing animals’ different approaches to solve a problem.     

Dominance and competence face to face: Dissociations obtained with a reverse correlation approach

The article explores whether the traits representing the dimensions underlying the structure of facial and non-facial impressions are similarly mapped in the face space. Two studies examine whether the trustworthiness-by-dominance and the warmth-by-competence two-dimensional models overlap in face perception. In Study 1 (N = 200), we used a reverse-correlation task to obtain classification images (CIs) reflecting how each dimension is mapped onto a face. Results show that the similarity between CIs was higher between warmth and trustworthiness than between competence and dominance. In Study 2 (N = 31) the evaluations of each CI on each social dimension show a higher dissociation between dominance and competence than between trustworthiness and warmth. These results, obtained at both perceptual and judgment levels, suggest that there is only a partial correspondence between the two models that seems to be driven by the relationship that the competence and dominance dimensions establish with valence.     

Repeated Play Reduces Video Games’ Ability to Elicit Guilt: Evidence from a Longitudinal Experiment

Statements supported mostly by correlational and cross-sectional studies suggest that playing violent video games can cause emotional desensitization. A longitudinal experiment examined a) whether repeated violent game play leads to emotional desensitization and b) whether desensitization generalizes to other play and real-life experiences. Participants played alternative versions of the same violent game for the first four days; on these days, the character role was varied between-subjects to be moral (United Nations soldier) or immoral (terrorist soldier). On Day 5, all participants played a novel game as a terrorist. Results indicate two things. First, habituation occurs over repeated game play: Repeated exposure decreased the ability of the original game to elicit guilt. Second, the decreased ability to elicit guilt can generalize to other game-play experiences: Guilt elicited by the novel game on Day 5 was reduced for the immoral character condition compared to the moral character condition. The current study provides causal, longitudinal evidence regarding the potential for video game play to lead to emotional desensitization with regard to future video game-play experiences.     

Value Priorities and Organ Donation in Young Adults

This research identifies major personal values among American university students that predict organ-donation registration with the Department of Motor Vehicles. Participants responded to a factual test of their knowledge about organ donation, indicated whether or not they had registered as posthumous donors, and filled out a personality inventory measuring their personal values (Schwartz, 1992, 1994). The data indicated a high level of factual knowledge about organ donation; and the greater the level of knowledge, the more likely participants were registered to donate their organs. Also, participants higher in benevolence, universalism, achievement, and stimulation were more likely to have registered to donate their organs. The results are discussed in terms of the need to develop more effective health-communication campaigns by using specific health-education messages tailored to students majoring in different disciplines or to people in various occupations as a means of increasing their willingness to donate.     

Facing Europe: visualizing spontaneous in-group projection

Individuals perceive their own group to be more typical of a shared superordinate identity than other groups are. This in-group projection process has been demonstrated with both self-report and indirect measures. The two studies reported here extend this research to the visual level, specifically, within the domain of faces. Using an innovative reverse-correlation approach, we found that German and Portuguese participants' visual representations of European faces resembled the appearance typical for their own national identity. This effect was found even among participants who explicitly denied that one nation was more typical of Europe than the other (Study 1). Moreover, Study 2 provides experimental evidence that in-group projection is restricted to inclusive superordinate groups, as the effect was not observed for visual representations of a category ("Australian") that did not include participants' in-group. Implications for the in-group projection model, as well as for the applicability of reverse-correlation paradigms, are discussed.     

Using accelerator pedal force to increase seat belt use of service vehicle drivers

This study evaluated a device that applied a sustained increase in accelerator pedal back force whenever drivers exceeded a preset speed criterion without buckling their seat belts. This force was removed once the belt was fastened. Participants were 6 commercial drivers who operated carpet-cleaning vans. During baseline, no contingency was in place for unbuckled trips. The pedal resistance was introduced via a multiple baseline design across groups. On the first day of treatment, the device was explained and demonstrated for all drivers of the vehicle. The treatment was associated with an immediate sustained increase in seat belt compliance to 100%. Occasionally, drivers initially did not buckle during a trip and encountered the force. In all instances, they buckled within less than 25 s. These results suggest that the increased force was sufficient to set up an establishing operation to reinforce seat belt buckling negatively. Drivers indicated that they were impressed with the device and would not drive very long unbelted with the pedal force in place.     

The effects of a rectangular rapid-flashing beacon on vehicle speed

In 2008, nearly 31% of vehicle fatalities were related to failure to adhere to safe vehicle speeds (National Highway Traffic Safety Administration [NHTSA], 2009). The current study evaluated the effect of a rectangular rapid-flashing beacon (RRFB) triggered by excessive speed on vehicle speed using a combined alternating treatments and reversal design. The percentage of vehicles traveling above 41 mph (66 km per hour) decreased by 20%, and speed distributions showed a shift toward lower speeds during the RRFB condition.