Lifeboat Foundation

UCLA department of integrative biology and physiologyluskin endowment for leadership symposiumpushing the boundaries: neuroscience, cognition, and lifemarta…

In 2022, scientists from Northwestern University presented novel observational data indicating that long gamma-ray bursts (GRBs) might originate from the collision of a neutron star with another dense celestial body, such as another neutron star or a black hole — a finding that was previously believed to be impossible.

Now, another Northwestern team offers a potential explanation for what generated the unprecedented and incredibly luminous burst of light.

Continue reading “Scientists Propose New Explanation for ‘Impossible’ Gamma-Ray Burst” »

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One thousand years into the future, humans might look like this.

Continue reading “What Will Humans Look Like in 1 Million Years?” »

Talk kindly contributed by Michael Levin in SEMF’s 2023 Interdisciplinary Summer School: https://semf.org.es/school2023/sessions.html#S1TALK ABSTRACTEach of u…

A new wave of scientists argues that mainstream evolutionary theory needs an urgent overhaul. Their opponents have dismissed them as misguided careerists – and the conflict may determine the future of biology.

Stephen Buranyi

One of the most actively debated questions about human and nonhuman culture is this: Under what circumstances might we expect culture, in particular the ability to learn from one another, to be favored by natural selection?

Researchers at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, have developed a simulation model of the evolution of social learning. They showed that the interplay between learning, memory and forgetting broadens the conditions under which we expect to see social learning to evolve.

Social learning is typically thought to be most beneficial when the environments in which individuals live change quite slowly—they can safely learn tried and tested information from one another and it does not go out of date quickly. Innovating brand-new information, on the other hand, is thought to be useful in dynamic and rapidly changing environments.

A new paper in the journal Genome Biology and Evolution, published by Oxford University Press, finds that genetic material from Neanderthal ancestors may have contributed to the propensity of some people today to be “early risers,” the sort of people who are more comfortable getting up and going to bed earlier.

Human Evolution and Genetic Adaptation

All anatomically modern humans trace their origin to Africa around 300 thousand years ago, where environmental factors shaped many of their biological features. Approximately seventy thousand years ago, the ancestors of modern Eurasian humans began to migrate out to Eurasia, where they encountered diverse new environments, including higher latitudes with greater seasonal variation in daylight and temperature.

Cortical gradient mapping stands as an innovative analytical tool for exploring the brain’s functional-spatial organization along a continuous spectrum^28,29,30, distinguishing it from conventional techniques reliant on discrete boundaries, e.g., functional parcellation in neuroimaging. As an intuitive metaphor, consider defining a geographic region by its boundary coordinates, which is akin to functional parcellation, versus describing it by elevation slopes or changes in vegetation types across various topographical axes, which is similar to gradient mapping. These cortical gradients span a wide spectrum of functions and networks, ranging from perception and action to higher-order cognitive processes²⁸. Notably, Gradient-1, known as the unimodal to transmodal gradient, enables the integration of sensory signals with non-sensory data, transforming them into abstract content. Gradient-2, the visual to somatomotor gradient, represents the specialization of different sensory modalities. Lastly, Gradient-3 spans functional distinctions ranging from regions typically deactivated during task performance (i.e., task-negative) to those activated in frontoparietal and attention networks (i.e., task-positive)^31,32. Despite promising foundations, the potential of gradients as a framework for analyzing and conceptualizing non-ordinary states of consciousness induced by psychedelics remains ripe for exploration.

In addition to the brain’s functional geometry, dynamic processes continuously mold and reconfigure functional arrangements, leading to the evolution of brain activity patterns over time^33,34. Recent empirical investigations have highlighted the intricate interplay between the spatial and temporal characteristics of brain activity, emphasizing that a comprehensive understanding necessitates the consideration of both aspects. Notably, transient fMRI co-activations^33,35,36 spanning the entire cortex have been observed to propagate like waves, following the spatially defined cortical gradients^37,38,39. Consequently, temporal dynamics are likely to be influenced by the underlying functional geometry. Exploring the co-variation between these spatial and temporal factors holds the potential to offer deeper insights into the neural underpinnings of psychedelic effects.

The objective of this study was to apply advanced cortical gradient mapping and co-activation pattern analysis to dissect the brain’s spatiotemporal reconfiguration during the psychedelic experience induced by nitrous oxide. Building upon previous research findings^16,25, we tested the hypothesis that nitrous oxide could diminish functional differentiation within the human cortex, as evidenced by a contraction in functional geometry and a disruption in temporal dynamics. We reanalyzed a neuroimaging dataset of healthy human volunteers, who were assessed by fMRI before and during exposure to psychedelic concentrations of nitrous oxide (35%, in oxygen) and who completed a validated altered states of consciousness questionnaire⁴⁰ before and after drug exposure. We quantified the changes of neural activity in cortical gradients and co-activations; we also performed correlation analyses to explore the relationship between subjective psychedelic experience and these brain measures. We demonstrate that nitrous oxide flattens the functional geometry of the cortex and disrupts related temporal dynamics, particularly within the frontoparietal and somatomotor networks, in association with the psychedelic experience.