Science posts

See science posts on page 31 below.

    • 2015
    • Bernard J. Crespi
    • Oxytocin, testosterone, and human social cognition
    • I describe an integrative social-evolutionary model for the adaptive significance of the human oxytocinergic system. The model is based on a role for this hormone in the generation and maintenance of social familiarity and affiliation across five homologous, functionally similar, and sequentially co-opted contexts: mothers with offspring, female and male mates, kin groups, individuals with reciprocity partners, and individuals within cooperating and competing social groups defined by culture. In each situation, oxytocin motivates, mediates and rewards the cognitive and behavioural processes that underlie the formation and dynamics of a more or less stable social group, and promotes a relationship between two or more individuals. Such relationships may be positive (eliciting neurological reward, reducing anxiety and thus indicating fitness-enhancing effects), or negative (increasing anxiety and distress, and thus motivating attempts to alleviate a problematic, fitness-reducing social ..
    • 2013
    • Anthony I. Jack et al.
    • Seeing human: Distinct and overlapping neural signatures associated with two forms of dehumanization
    • The process of dehumanization, or thinking of others as less than human, is a phenomenon with significant societal implications. According to Haslam's (2006) model, two concepts of humanness derive from comparing humans with either animals or machines: individuals may be dehumanized by likening them to either animals or machines, or humanized by emphasizing differences from animals or machines. Recent work in cognitive neuroscience emphasizes understanding cognitive processes in terms of interactions between distributed cortical networks. It has been found that reasoning about internal mental states is associated with activation of the default mode network (DMN) and deactivation of the task positive network (TPN); whereas reasoning about mechanical processes produces the opposite pattern. We conducted two neuroimaging studies. The first examined the neural bases of dehumanization and its relation to these two brain networks, using images and voice-over social narratives which either ..
    • 2014
    • Kalina Christoff
    • Dehumanization in organizational settings: some scientific and ethical considerations
    • Dehumanizing attitudes and behaviors frequently occur in organizational settings and are often viewed as an acceptable, and even necessary, strategy for pursuing personal and organizational goals. Here I examine a number of commonly held beliefs about dehumanization and argue that there is relatively little support for them in light of the evidence emerging from social psychological and neuroscientific research. Contrary to the commonly held belief that everyday forms of dehumanization are innocent and inconsequential, the evidence shows profoundly negative consequences for both victims and perpetrators. As well, the belief that suppressing empathy automatically leads to improved problem solving is not supported by the evidence. The more general belief that empathy interferes with problem solving receives partial support, but only in the case of mechanistic problem solving. Overall, I question the usefulness of dehumanization in organizational settings and argue that it can be replac..
    • 2014
    • Justin Sytsma
    • Attributions of consciousness
    • Many philosophers and brain scientists hold that explaining consciousness is one of the major outstanding problems facing modern science today. One type of consciousness in particular—phenomenal consciousness—is thought to be especially problematic. The reasons given for believing that this phenomenon exists in the first place, however, often hinge on the claim that its existence is simply obvious in ordinary perceptual experience. Such claims motivate the study of people's intuitions about consciousness. In recent years a number of researchers in experimental philosophy of mind have begun to shed light on this area, investigating how people understand and attribute those mental states that have been thought to be phenomenally conscious. In this article, we discuss the philosophical concept of phenomenal consciousness and detail the work that has been done on the question of whether lay people have this concept.
    • 2003
    • Olivier Houdé & Nathalie Tzourio-Mazoyer
    • Neural foundations of logical and mathematical cognition
    • Brain-imaging techniques have made it possible to explore the neural foundations of logical and mathematical cognition. These techniques are revealing more than simply where these high-order processes take place in the human cortex. Imaging is beginning to answer some of the oldest questions about what logic and mathematics are, and how they emerge and evolve through visuospatial cognition, language, executive functions and emotion.
    • 2006
    • Olivier Houdé et al.
    • Shifting from the Perceptual Brain to the Logical Brain: The Neural Impact of Cognitive Inhibition Training
    • What happens in the human brain when the mind has to inhibit a perceptual process in order to activate a logical reasoning process? Here, we use functional imaging to show the networks of brain areas involved in a deductive logic task performed twice by the same subjects, first with a perceptual bias and then with a logical response following bias-inhibition training. The main finding is a striking shift in the cortical anatomy of reasoning from the posterior part of the brain (the ventral and dorsal pathways) to a left-prefrontal network including the middle-frontal gyrus, Broca's area, the anterior insula, and the pre-SMA. This result indicates that such brain shifting is an essential element for human access to logical thinking.
    • 2007
    • Jérôme Prado et al.
    • Overcoming Perceptual Features in Logical Reasoning: A Parametric Functional Magnetic Resonance Imaging Study
    • Participants experience difficulty detecting that an item depicting an H-in-a-square confirms the logical rule, “If there is not a T then there is not a circle.” Indeed, there is a perceptual conflict between the items mentioned in the rule (T and circle) and in the test item (H and square). Much evidence supports the claim that correct responding depends on detecting and resolving such conflicts. One aim of this study is to find more precise neurological evidence in support of this claim by using a parametric event-related functional magnetic resonance imaging (fMRI) paradigm. We scanned 20 participants while they were required to judge whether or not a conditional rule was verified (or falsified) by a corresponding target item. We found that the right middorsolateral prefrontal cortex (mid-DLPFC) was specifically engaged, together with the medial frontal (anterior cingulate and presupplementary motor area [pre-SMA]) and parietal cortices, when mismatchin..
    • 2004
    • Jonathan A. Fugelsang et al.
    • Brain-based mechanisms underlying complex causal thinking
    • We use functional magnetic resonance imaging (fMRI) and behavioral analyses to study the neural roots of biases in causal reasoning. Fourteen participants were given a task requiring them to interpret data relative to plausible and implausible causal theories. Encountering covariation-based data during the evaluation of a plausible theory as opposed to an implausible theory selectively recruited neural tissue in the prefrontal and occipital cortices. In addition, the plausibility of a causal theory modulated the recruitment of distinct neural tissue depending on the extent to which the data were consistent versus inconsistent with the theory provided. Specifically, evaluation of data consistent with a plausible causal theory recruited neural tissue in the parahippocampal gyrus, whereas evaluating data inconsistent with a plausible theory recruited neural tissue in the anterior cingulate, left dorsolateral prefrontal cortex, and precuneus. We suggest that these findings provide a neur..
    • 2010
    • Stollstorff, Melanie Louise
    • Modulation of reasoning bias and brain activation by serotonin transporter genotype and emotional content
    • Thesis (Ph.D.)--Georgetown University, 2010.; Includes bibliographical references.; Text (Electronic thesis) in PDF format. Deductive reasoning is influenced by emotions and beliefs. It is unknown how factors relating to emotion and beliefs interact to affect logical reasoning. This dissertation explored the nature of emotion-belief interactions in relational reasoning using behavioral, genetic and neuroimaging techniques. In Study 1, reasoning behavior was influenced by beliefs such that participants were less accurate and slower to evaluate arguments in which the conclusion validity conflicted with beliefs, thereby replicating the belief bias effect. Moreover, belief-bias interacted with emotional content and serotonin transporter genotype; carriers of the short (S) allele of the serotonin transporter gene (5-HTTLPR) had increased emotional belief bias relative to long (L) carriers. Groups did not differ in non-emotional belief bias. In Study 2, I investigated the neural basis for ..
    • 2015
    • Caroline Lustenberger et al.
    • Functional role of frontal alpha oscillations in creativity
    • Creativity, the ability to produce innovative ideas, is a key higher-order cognitive function that is poorly understood. At the level of macroscopic cortical network dynamics, recent electroencephalography (EEG) data suggests that cortical oscillations in the alpha frequency band (8–12 Hz) are correlated with creative thinking. However, whether alpha oscillations play a fundamental role in creativity has remained unknown. Here we show that creativity is increased by enhancing alpha power using 10 Hz transcranial alternating current stimulation (10 Hz-tACS) of the frontal cortex. In a study of 20 healthy participants with a randomized, balanced cross-over design, we found a significant improvement of 7.4% in the Creativity Index measured by the Torrance Test of Creative Thinking (TTCT), a comprehensive and most frequently used assay of creative potential and strengths. In a second similar study with 20 subjects, 40 Hz-tACS was used in instead of 10 Hz-tACS to rule out a ..