Against The Grain: A Deep History of the Earliest States is a 2017 book by James C. Scott that sets out to undermine what he calls the “standard civilizational narrative” that suggests humans chose to live settled lives based on intensive agriculture because this made people safer and more prosperous. Instead, he argues, people had to be forced to live in the early states, which were hierarchical, beset by malnutrition and disease, and often based on slavery. The book has been praised for re-opening some of the biggest questions in human history. A review in Science concludes that the book’s thesis “is fascinating and represents an alternative, nuanced, if somewhat speculative, scenario on how civilized society came into being.”
From one of our preeminent neuroscientists: a landmark reflection that spans the biological and social sciences, offering a new way of understanding the origins of life, feeling, and culture.
The Strange Order of Things is a pathbreaking investigation into homeostasis, the condition of that regulates human physiology within the range that makes possible not only the survival but also the flourishing of life. Antonio Damasio makes clear that we descend biologically, psychologically, and even socially from a long lineage that begins with single living cells; that our minds and cultures are linked by an invisible thread to the ways and means of ancient unicellular life and other primitive life-forms; and that inherent in our very chemistry is a powerful force, a striving toward life maintenance that governs life in all its guises, including the development of genes that help regulate and transmit life. In The Strange Order of Things, Damasio gives us a new way of comprehending the world and our place in it.
Jo Boaler is a professor of mathematics education at Stanford and the co-founder of youcubed.
Women’s brain health remains one of the most under-researched, under-diagnosed and undertreated fields of medicine. Women are twice as likely as men to develop Alzheimer’s and twice as likely to become anxious or depressed. They are four times more likely to suffer with headaches and migraines and they are more prone to brain tumours and strokes than men. Today’s guest says this is a clear indication of functional differences between female and male brains. And she’s made it her life’s work to learn more about it. Neuroscientist Dr Lisa Mosconi is director of the Women’s Brain Initiative and works at the Alzheimer’s Prevention Clinic at Weill Cornell Medical College, US, where she studies how genetics, lifestyle and nutrition shape brain health, particularly in women. Lisa describes her frustration at constantly being told by peers that the reason Alzheimer’s was more prevalent in women was simply because they live longer, and it’s a disease of ageing. We discuss her ground-breaking research that has exposed this bias, finding dementia brain changes can actually begin in midlife, triggered by declining oestrogen during perimenopause. Worrying as that might sound, this discovery will enable women to take control of their risk at a much earlier age. Lisa goes on to share plenty of practical, evidence-based advice to help you do that. I was really moved to hear Lisa talk about the beautiful changes that happen in the female brain during pregnancy and post-partum. It’s a new take on the idea of ‘Mummy brain’ and will be validating for all mothers out there to hear. She also gives a clear and candid explanation of how perimenopause alters brain function. So many of my patients in their 40s and 50s are scared by changes like forgetfulness, brain fog and anxiety. If that’s you or someone you know, Lisa’s insights and advice will be really empowering. I’m a passionate advocate for women’s health equality. Yet chatting with Lisa made me realise how much more work we all have to do to get topics like these out there and understood. This conversation is relevant to all of us, women and men alike. I hope it gets you thinking and talking more.
Two lines of evidence indicate that there exists a reciprocal inhibitory relationship between opposed brain networks. First, most attention-demanding cognitive tasks activate a stereotypical set of brain areas, known as the task-positive network and simultaneously deactivate a different set of brain regions, commonly referred to as the task negative or default mode network. Second, functional connectivity analyses show that these same opposed networks are anti-correlated in the resting state. We hypothesize that these reciprocally inhibitory effects reflect two incompatible cognitive modes, each of which is directed towards understanding the external world. Thus, engaging one mode activates one set of regions and suppresses activity in the other. We test this hypothesis by identifying two types of problem-solving task which, on the basis of prior work, have been consistently associated with the task positive and task negative regions: tasks requiring social cognition, i.e., reasoning about the mental states of other persons, and tasks requiring physical cognition, i.e., reasoning about the causal/mechanical properties of inanimate objects. Social and mechanical reasoning tasks were presented to neurologically normal participants during fMRI. Each task type was presented using both text and video clips. Regardless of presentation modality, we observed clear evidence of reciprocal suppression: social tasks deactivated regions associated with mechanical reasoning and mechanical tasks deactivated regions associated with social reasoning. These findings are not explained by self-referential processes, task engagement, mental simulation, mental time travel or external vs. internal attention, all factors previously hypothesized to explain default mode network activity. Analyses of resting state data revealed a close match between the regions our tasks identified as reciprocally inhibitory and regions of maximal anti-correlation in the resting state. These results indicate the reciprocal inhibition is not attributable to constraints inherent in the tasks, but is neural in origin. Hence, there is a physiological constraint on our ability to simultaneously engage two distinct cognitive modes. Further work is needed to more precisely characterize these opposing cognitive domains.
A number of recent advances have been achieved in the study of midbrain dopaminergic neurons. Understanding these advances and how they relate to one another requires a deep understanding of the computational models that serve as an explanatory framework and guide ongoing experimental inquiry. This intertwining of theory and experiment now suggests very clearly that the phasic activity of the midbrain dopamine neurons provides a global mechanism for synaptic modification. These synaptic modifications, in turn, provide the mechanistic underpinning for a specific class of reinforcement learning mechanisms that now seem to underlie much of human and animal behavior. This review describes both the critical empirical findings that are at the root of this conclusion and the fantastic theoretical advances from which this conclusion is drawn.
The theory and data available today indicate that the phasic activity of midbrain dopamine neurons encodes a reward prediction error used to guide learning throughout the frontal cortex and the basal ganglia. Activity in these dopaminergic neurons is now believed to signal that a subject’s estimate of the value of current and future events is in error and indicate the magnitude of this error. This is a kind of combined signal that most scholars active in dopamine studies believe adjusts synaptic strengths in a quantitative manner until the subject’s estimate of the value of current and future events is accurately encoded in the frontal cortex and basal ganglia. Although some confusion remains within the larger neuroscience community, very little data exist that are incompatible with this hypothesis. This review provides a brief overview of the explanatory synergy between behavioral, anatomical, physiological, and biophysical data that has been forged by recent computational advances. For a more detailed treatment of this hypothesis, refer to Niv and Montague (1) or Dayan and Abbot (2).
Learning and motivation are driven by internal and external rewards. Many of our day-to-day behaviours are guided by predicting, or anticipating, whether a given action will result in a positive (that is, rewarding) outcome. The study of how organisms learn from experience to correctly anticipate rewards has been a productive research field for well over a century, since Ivan Pavlov’s seminal psychological work. In his most famous experiment, dogs were trained to expect food some time after a buzzer sounded. These dogs began salivating as soon as they heard the sound, before the food had arrived, indicating they’d learned to predict the reward. In the original experiment, Pavlov estimated the dogs’ anticipation by measuring the volume of saliva they produced. But in recent decades, scientists have begun to decipher the inner workings of how the brain learns these expectations. Meanwhile, in close contact with this study of reward learning in animals, computer scientists have developed algorithms for reinforcement learning in artificial systems. These algorithms enable AI systems to learn complex strategies without external instruction, guided instead by reward predictions.
The contribution of our new work, published in Nature (PDF), is finding that a recent development in computer science – which yields significant improvements in performance on reinforcement learning problems – may provide a deep, parsimonious explanation for several previously unexplained features of reward learning in the brain, and opens up new avenues of research into the brain’s dopamine system, with potential implications for learning and motivation disorders.
“Would you like a little choice in your life?” ” Do you need to be able to decide for yourself?” “Do you love it when you get to follow your own emergence?” One of the needs that is most missing in our world, from childhood, through work, and on through old age, is the need for self-determination. What changes can we make so that this energy is more alive for us in our lives? What unconscious contracts can we release to make sure that we have a sense of freedom? And what is happening in the brain with the longing for choice, and what happens when that need is met? In this 90-minute session, we’ll learn a little about the brain, a little about unconscious contracts, and a lot about ourselves.
The amygdala and hippocampal complex, two medial temporal lobe structures, are linked to two independent memory systems, each with unique characteristic functions. In emotional situations, these two systems interact in subtle but important ways. Specifically, the amygdala can modulate both the encoding and the storage of hippocampal-dependent memories. The hippocampal complex, by forming episodic representations of the emotional significance and interpretation of events, can influence the amygdala response when emotional stimuli are encountered. Although these are independent memory systems, they act in concert when emotion meets memory.
Typically the term “memory” refers to the ability to consciously remember past experiences or previously learned information. This kind of memory is considered to be dependent upon the hippocampal system. However, our emotional state seems to considerably affect the way in which we retain information and the accuracy with which the retention occurs. The amygdala is the most notably involved brain structure in emotional responses and the formation of emotional memories. In this review we describe a system, composed of the amygdala and the hippocampus, that acts synergistically to form long-term memories of significantly emotional events. These brain structures are activated following an emotional event and cross-talk with each other in the process of consolidation. This dual activation of the amygdala and the hippocampus and the dynamics between them may be what gives emotionally based memories their uniqueness.