Social cognitive processes explain bias in juror decisions

Jury decisions are among the most consequential social decisions in which bias plays a notable role. While courts take measures to reduce the influence of non-evidentiary factors, jurors may still incorporate biases into their decisions. One common bias, crime-type bias, is the extent to which the perceived strength of a prosecutor&rsquo;s case depends on the severity of the crime. Moral judgment, affect and social cognition have been proposed as core processes underlying this and other biases. Behavioral evidence alone has been insufficient to distinguish these explanations. To identify the mechanism underlying crime-type bias, we collected functional magnetic resonance imaging patterns of brain activation from mock jurors reading criminal scenarios. Brain patterns from crime-type bias were most similar to those associated with social cognition (mentalizing and racial bias) but not affect or moral judgment. Our results support a central role for social cognition in juror decisions and suggest that crime-type bias and cultural bias may arise from similar mechanisms. &nbsp;</p

Social connections predict brain structure in a multidimensional free-ranging primate society

Reproduction and survival in most primate species reflects management of both competitive and cooperative relationships. Here, we investigated the links between neuroanatomy and sociality in free-ranging rhesus macaques. In adults, the number of social partners predicted the volume of the mid–superior temporal sulcus and ventral-dysgranular insula, implicated in social decision-making and empathy, respectively. We found no link between brain structure and other key social variables such as social status or indirect connectedness in adults, nor between maternal social networks or status and dependent infant brain structure. Our findings demonstrate that the size of specific brain structures varies with the number of direct affiliative social connections and suggest that this relationship may arise during development. These results reinforce proposed links between social network size, biological success, and the expansion of specific brain circuits

A transcription-dependent switch controls competence of adult neurons for distinct modes of axon growth

Although maturing neurons undergo a precipitous decline in the expression of genes associated with developmental axon growth, structural changes in axon arbors occur in the adult nervous system under both normal and pathological conditions. Furthermore, some neurons support extensive regrowth of long axons after nerve injury. Analysis of adult dorsal root ganglion (DRG) neurons in culture now shows that competence for distinct types of axon growth depends on different patterns of gene expression. In the absence of ongoing transcription, newly isolated neurons can extend compact, highly branched arbors during the first day in culture. Neurons subjected to peripheral axon injury 2–7 d before plating support a distinct mode of growth characterized by rapid extension of long, sparsely branched axons. A transition from “arborizing ” to “elongating ” growth occurs in naive adult neurons after �24 h

Social cognitive processes explain bias in juror decisions

Jury decisions are among the most consequential social decisions in which bias plays a notable role. While courts take measures to reduce the influence of non-evidentiary factors, jurors may still incorporate biases into their decisions. One common bias, crime-type bias, is the extent to which the perceived strength of a prosecutor’s case depends on the severity of the crime. Moral judgment, affect, and social cognition have been proposed as core processes underlying this and other biases. Behavioral evidence alone has been insufficient to distinguish these explanations. To identify the mechanism underlying crime-type bias, we collected fMRI patterns of brain activation from mock jurors reading criminal scenarios. Brain patterns from crime-type bias were most similar to those associated with social cognition (mentalizing and racial bias) but not affect or moral judgment. Our results support a central role for social cognition in juror decisions and suggest crime-type bias and cultural bias may arise from similar mechanisms

Diversity and evolution of the primate skin microbiome

Skin microbes play a role in human body odour, health and disease. Compared with gut microbes, we know little about the changes in the composition of skin microbes in response to evolutionary changes in hosts, or more recent behavioural and cultural changes in humans. No studies have used sequence-based approaches to consider the skin microbe communities of gorillas and chimpanzees, for example. Comparison of the microbial associates of non-human primates with those of humans offers unique insights into both the ancient and modern features of our skin-associated microbes. Here we describe the microbes found on the skin of humans, chimpanzees, gorillas, rhesus macaques and baboons. We focus on the bacterial and archaeal residents in the axilla using high-throughput sequencing of the 16S rRNA gene. We find that human skin microbial communities are unique relative to those of other primates, in terms of both their diversity and their composition. These differences appear to reflect both ancient shifts during millions of years of primate evolution and more recent changes due to modern hygiene

Vliv fyzikálních faktorů vnějšího prostředí na psychiku člověka

This files contains operational taxonomic units at the genera level (L6) from our primate armpit samples after rarefaction at 1,000 reads

Data from: Diversity and evolution of the primate skin microbiome

Skin microbes play a role in human body odour, health and disease. Compared to gut microbes we know comparatively little about the changes in the composition of skin microbes in response to evolutionary changes in hosts, or more recent behavioral and cultural changes in humans. No studies have used sequence-based approaches to consider the skin microbe communities of gorillas and chimpanzees, for example. Comparison of the microbial associates of non-human primates with those of humans offers unique insights into both the ancient and modern features of our skin associated microbes. Here we describe the microbes found on the skin of humans, chimpanzees, gorillas, rhesus macaques and baboons. We focus on the bacterial and Archaeal residents in the axilla using high throughput sequencing of the 16S rRNA gene. We find that human skin microbial communities are unique relative to those of other primates, both in terms of their diversity and composition. These differences appear to reflect both ancient shifts during millions of years of primate evolution and more recent changes due to modern hygiene