Who moved my cheese? How about who moved my tail? This past spring, a team of researchers successfully linked the brains of a human and a rat, such that a human participant was able to move a rat’s tail with only his thoughts. Through a noninvasive approach, Yoo et al. used an image of a flashing strobe light to prompt specific brain signals in the human participant, which were then translated into the appropriate neural stimulus for the rat, and thus invoke the movement of the rat’s tail. Methodologically, Yoo et al. were able to achieve this brain-to-brain interface by successfully translating, computer recorded, EEG signals of the human brain into a transcranial focused ultrasound (FUS) burst, which stimulated the area in the rat’s motor cortex corresponding to tail movement. Though Yoo and colleagues acknowledge the potential for brain-to-brain communication between humans, they approach expanding upon mind control technology with caution, as further advancements pose questions of ethics that remain unanswered.
- Yoo S-S, Kim H, Filandrianos E, Taghados SJ, Park S (2013) Non-Invasive Brain-to-Brain Interface (BBI): Establishing Functional Links between Two Brains.PLoS ONE 8(4): e60410.
The creation of the Implicit Association Test (IAT), in 1998, sparked a new wave of theory and research focused on understanding people’s implicitly held attitudes and beliefs, and how those implicit attitudes and beliefs might affect behavior. One of most researched topics using IAT methodology is racial and ethnic discrimination. Employing the IAT, many researchers seemed to uncover implicit biases and prejudices that explicit measures, specifically because they were explicit, could not uncover. However, a new meta analysis, by Oswald et al. revealed the IAT to be a poor predictor of racial or ethnic discriminatory attitudes and behavior, and in fact no better than an explicit measure. Given these results, Oswald et al. question the construct validity of the IAT, and in turn its ability to predict actual behavior. These new findings raise significant questions about psychology and other domains widespread use and application of IAT based results, specifically with regard to racial and ethnic discrimination, and have broad implications for the legal system that has made significant use of the IAT since its inception 15 years ago.
- Oswald, F. L., Mitchell, G., Blanton, H., Jaccard, J., & Tetlock, P. E. (2013). Predicting Ethnic and Racial Discrimination: A Meta-Analysis of IAT Criterion Studies. Journal of personality and social psychology, 105(2), 171-192.
Born on third base and thought you hit a triple. A recent study by Kraus and Keltner showed that individuals who perceived themselves as higher in social class rank tended to understand their elevated position in essentialist terms. That is, high social rank individuals tended to believe that differences in social standing can be explained by natural or inherent factors, rather than the social-situation context. This effect held, even for participants whose perception of their social class rank was experimentally manipulated to be relatively higher, which, the researchers suggest, points to an initial causal link between high class rank and the tendency to adopt essentialist beliefs about social class. Kraus and Keltner also demonstrated that individuals who were more likely to explain social rank in terms of natural ability, were less likely to favor restorative justice, the idea that criminals should be rehabilitated, as opposed to retributive justice, which is based on the idea of deterrents. This research has implications for how people perceive social mobility and class, and the researchers pose a question for future research: “Do essentialist beliefs in social hierarchy underlie current punishment practices in the United States?”
- Kraus, M. W., & Keltner, D. (2013). Social Class Rank, Essentialism, and Punitive Judgment. Journal of personality and social psychology, 105(2), 247-261.
Did you see the gorilla? Contributing to the growing body of evidence on inattentional blindness, –the phenomenon that people often fail to recognize salient stimuli while engaged in another task–Drew et al. performed a study that examined how expert radiologists would fare if an anomalous stimuli was placed in lung CT scans. In the experiment, professional radiologists were tasked with detecting cancer nodes in 5 chest CT scans. In the final scan, the experimenters inserted the outline of a gorilla. Of the 24 radiologists who performed the task, 20 missed the gorilla. Eye tracking data of the radiologists who “did not see” the gorilla, indicated that the majority had looked directly at its position. The researchers suggest these results illustrate that even individuals with high levels of expertise can still fall victim to the limits of attention and perception. This work has implications for understanding how mistakes can be avoided during search tasks, especially in the healthcare industry, where the consequences of missed information can be catastrophic.
- Drew, T., Võ, M. L. H., & Wolfe, J. M. (2013). The Invisible Gorilla Strikes Again Sustained Inattentional Blindness in Expert Observers.Psychological science. Published online before print July 17, 2013.
Unable to overcome the gauntlet of cravings and withdrawal, alcohol abusers often succumb to relapse. However, a recent article in Nature Neuroscience describes a potential avenue of treatment that may aid with recovery. According to Barak et al., the tastes and smells associated with alcohol cue memories that evoke cravings, and thus spur relapse. Using alcohol dependent rats, Barak et al. found that by inhibiting a memory related pathway, they were able to mitigate cravings for alcohol in the rats. In the study, the researchers first identified the activation of the mTORC1 neural pathway as part of the memory reconsolidation process, and subsequently hypothesized that inhibiting this pathway could disrupt alcohol related memories and ultimately suppress relapse. As predicted, Barak and his team found that the mTORC1 inhibitor, rapamycin, effectively suppressed relapse in alcohol dependent rats that had been prompted with alcohol related taste and smell cues. This finding–that disruption of a neural pathway related to memory consolidation can lead to clinical benefits–has implications for the treatment of alcohol and substance abuse, as well as for clinical conditions involving recurrent memories, such as PTSD.
- Barak, S., Liu, F., Hamida, S. B., Yowell, Q. V., Neasta, J., Kharazia, V., … & Ron, D. (2013). Disruption of alcohol-related memories by mTORC1 inhibition prevents relapse. Nature Neuroscience, 16, 1111–1117.
How did human cooperation evolve? In review of both the theoretical and empirical research, Rand and Nowak set out to understand the theoretical frames of cooperation alongside the behavioral evidence. Theory suggests that human cooperation developed via five different mechanisms: reciprocity, reputation, group interaction, competition, and kin recognition. These mechanisms are significant, the theory posits, because within these behavioral patterns cooperation was favored from a reproduction and selection standpoint. Drawing on research in game theory, the authors present the existing behavioral evidence for each of the five identified mechanisms, in order to describe why and how, in a seemingly competitive world, cooperative behavior developed. The authors also examine one-off instances of cooperation where no mechanism was involved. They conclude that regularly used cooperative strategies often “spill over” to affect anonymous, one time interactions. Lastly, the authors suggest avenues for future research and ways in which the fields of Evolutionary Dynamics and Psychology can work together to better understand human cooperation.