Origins of modern human ancestry

New finds in the palaeoanthropological and genomic records have changed our view of the origins of modern human ancestry. Here we review our current understanding of how the ancestry of modern humans around the globe can be traced into the deep past, and which ancestors it passes through during our journey back in time. We identify three key phases that are surrounded by major questions, and which will be at the frontiers of future research. The most recent phase comprises the worldwide expansion of modern humans between 40 and 60thousand years ago (ka) and their last known contacts with archaic groups such as Neanderthals and Denisovans. The second phase is associated with a broadly construed African origin of modern human diversity between 60 and 300ka. The oldest phase comprises the complex separation of modern human ancestors from archaic human groups from 0.3 to 1million years ago. We argue that no specific point in time can currently be identified at which modern human ancestry was confined to a limited birthplace, and that patterns of the first appearance of anatomical or behavioural traits that are used to define Homo sapiens are consistent with a range of evolutionary histories.

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Father’s Early-Life Exposure to Stress Associated With Child’s Brain Development

Stress experienced by fathers during early life was associated with more rapid development of white matter tracts in his child’s brain.

The FinnBrain research of the University of Turku has demonstrated for the first time that the stress the father has experienced in his childhood is connected to the development of the white matter tracts in the child’s brain. Whether this connection is transmitted through epigenetic inheritance needs further research.

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Fathers, your stress could affect your child’s brain

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Traumatic Stress in Childhood Can Lead to Brain Changes in Adulthood

Experiencing trauma or extreme stress during childhood can lead to structural changes in the hippocampus and amygdala that can be seen decades later.urce: University of Alberta

A new study from University of Alberta researchers has shown that traumatic or stressful events in childhood may lead to tiny changes in key brain structures that can now be identified decades later.

Conclusion: Our results provide evidence of negative associations between history of childhood maltreatment and volumes of medial temporal lobe structures in participants with MDD. This may help to identify potential mechanisms by which maltreatment leads to clinical impacts.

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Building a strong immune system that could defeat COVID-19

You may not know it, but you have an army of microbes living inside of you that are essential for fighting off threats, including the virus that causes COVID-19.

In the past two decades scientists have learned our bodies are home to more bacterial cells than human ones. This community of bacteria that lives in and on us – called the microbiome – resembles a company, with each microbe species performing specialized jobs but all working to keep us healthy. In the gut, the bacteria balance the immune response against pathogens. These bacteria ensure the immune response is effective but not so violent that it causes collateral damage to the host.

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On Having No Head: Cognition throughout Biological Systems

The central nervous system (CNS) underlies memory, perception, decision-making, and behavior in numerous organisms. However, neural networks have no monopoly on the signaling functions that implement these remarkable algorithms. It is often forgotten that neurons optimized cellular signaling modes that existed long before the CNS appeared during evolution, and were used by somatic cellular networks to orchestrate physiology, embryonic development, and behavior. Many of the key dynamics that enable information processing can, in fact, be implemented by different biological hardware. This is widely exploited by organisms throughout the tree of life. Here, we review data on memory, learning, and other aspects of cognition in a range of models, including single celled organisms, plants, and tissues in animal bodies. We discuss current knowledge of the molecular mechanisms at work in these systems, and suggest several hypotheses for future investigation. The study of cognitive processes implemented in aneural contexts is a fascinating, highly interdisciplinary topic that has many implications for evolution, cell biology, regenerative medicine, computer science, and synthetic bioengineering.

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Education Inequalities Linked to Increased Cognitive Aging in Women

Older women tended to have poorer memory fluidity scores than men of the same age group. However, the reverse was true for younger women. Researchers propose the difference could be a result of younger women having more access to higher education than previous generations.

Background Previous studies have shown an excess risk of Alzheimer’s disease and related dementias among women. Education is thought to have a causal association with dementia onset. We aimed to investigate the role of education in influencing sex differences in cognitive ageing.

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The Origin of Mind: Evolution of Brain, Cognition, and General Intelligence

Darwin considered an understanding of the evolution of the human mind and brain to be of major importance to the evolutionary sciences. This groundbreaking book sets out a comprehensive, integrated theory of why and how the human mind has developed to function as it does. Geary proposes that human motivational, affective, behavioral, and cognitive systems have evolved to process social and ecological information (e.g., facial expressions) that covaried with survival or reproductive options during human evolution. Further, he argues that the ultimate focus of all of these systems is to support our attempts to gain access to and control of resources – more specifically, the social (e.g., mates), biological (e.g., food), and physical (e.g., territory) resources that supported successful survival and reproduction over time. In this view, Darwin’s conceptualization of natural selection as a struggle for existence becomes, for us, a struggle with other human beings for control of the available resources. This struggle provides a means of integrating modular brain and cognitive systems such as language with those brain and cognitive systems that support general intelligence. findings in cognitive science and neuroscience as well as primatology, anthropology, and sociology. The book also explores a number of issues that are of interest in modern society, including how general intelligence relates to academic achievement, occupational status, and income. Readers will find this book a thought-provoking read and an impetus for new theories of mind.

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Mind and Self in Society: Linking Social Structure and Social Cognition

Recent developments in social cognition could enhance sociological social psychologists’ understanding of the mind as both a social product and a social force; yet this work in social cognition has received little attention. Conversely, social cognition has not fulfilled its promise to show what is truly social about cognition. We argue that more attention to social cognition on the part of sociologist would be beneficial to both fields, as would more attention to social structure on the part of those working in social cognition. After brief overview of social cognition we examine the self and self-concept and role theory as two substantive areas that provide immediate opportunities for connecting sociological social psychology and social cognition. In both areas we consider both the American version of social cognition and the European approach, which is based on social representations. We conclude that sociological social psychology can make a unique contribution to understanding how social structure and social cognition are linked.

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Brain Mechanisms of Concept Learning

Concept learning, the ability to extract commonalities and highlight distinctions across a set of related experiences to build organized knowledge, is a critical aspect of cognition. Previous reviews have focused on concept learning research as a means for dissociating multiple brain systems. The current review surveys recent work that uses novel analytical approaches, including the combination of computational modeling with neural measures, focused on testing theories of specific computations and representations that contribute to concept learning. We discuss in detail the roles of the hippocampus, ventromedial prefrontal, lateral prefrontal, and lateral parietal cortices, and how their engagement is modulated by the coherence of experiences and the current learning goals. We conclude that the interaction of multiple brain systems relating to learning, memory, attention, perception, and reward support a flexible concept-learning mechanism that adapts to a range of category structures and incorporates motivational states, making concept learning a fruitful research domain for understanding the neural dynamics underlying complex behaviors.

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Future choices may be guided by our memories of past ones

When it comes to making choices, past decisions may play a surprisingly large role. The traditional view of decision-making is that our choices are guided by what we remember about the outcomes of previous choices we’ve made. But in recent years, a complementary idea has arisen: that the mere memory of the choices we make, whatever their outcome, may affect future decisions.

Essentially, this idea posits that “when you’re deciding between two options that are roughly equivalent, you tend to prefer the previously chosen option over the other non-chosen option,” explains Lennart Luettgau, a cognitive science graduate student at Heinrich Heine University in Düsseldorf, Germany. In a recent paper in Nature Communications, he and his colleagues set out to look for evidence in the brain that might support such two-way influence between choice and memory.

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