Lifeboat Foundation

Consciousness is comprised of arousal (i.e., wakefulness) and awareness. Substantial progress has been made in mapping the cortical networks that modulate awareness in the human brain, but knowledge about the subcortical networks that sustain arousal is lacking. We integrated data from ex vivo diffusion MRI, immunohistochemistry, and in vivo 7 Tesla functional MRI to map the connectivity of a subcortical arousal network that we postulate sustains wakefulness in the resting, conscious human brain, analogous to the cortical default mode network (DMN) that is believed to sustain self-awareness. We identified nodes of the proposed default ascending arousal network (dAAN) in the brainstem, hypothalamus, thalamus, and basal forebrain by correlating ex vivo diffusion MRI with immunohistochemistry in three human brain specimens from neurologically normal individuals scanned at 600–750 µm resolution. We performed deterministic and probabilistic tractography analyses of the diffusion MRI data to map dAAN intra-network connections and dAAN-DMN internetwork connections. Using a newly developed network-based autopsy of the human brain that integrates ex vivo MRI and histopathology, we identified projection, association, and commissural pathways linking dAAN nodes with one another and with cortical DMN nodes, providing a structural architecture for the integration of arousal and awareness in human consciousness. We release the ex vivo diffusion MRI data, corresponding immunohistochemistry data, network-based autopsy methods, and a new brainstem dAAN atlas to support efforts to map the connectivity of human consciousness.

One sentence summary We performed ex vivo diffusion MRI, immunohistochemistry, and in vivo 7 Tesla functional MRI to map brainstem connections that sustain wakefulness in human consciousness.

BF has a financial interest in CorticoMetrics, a company whose medical pursuits focus on brain imaging and measurement technologies. BF’s interests were reviewed and are managed by Massachusetts General Hospital and Mass General Brigham HealthCare in accordance with their conflict-of-interest policies.

Is consciousness a scientific problem to be solved? Or a philosophical problem that will remain a mystery? What do scientists who study the brain think? And why do they think the way they do? These leading brain scientists share their intimate ideas about how the brain generates consciousness.

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Amy Arnsten — Yale University.

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We were privileged to host the extraordinary Dr. Michael Levin, an eminent scientist and esteemed developmental and synthetic biologist, for a truly exceptional event titled \.

What Matters to Me and Why is a series of virtual presentations followed by discussion that goes beyond the great research we’ve heard about: To give our community a chance to get to know how our faculty came to their topics and—in their own words—what inspires and is important to them!

An international team of researchers of the Cluster of Excellence “Balance of the Microverse” at the University of Jena has investigated the mechanism that makes some types of bacteria reflect light without using pigments. The researchers were interested in the genes responsible and discovered important ecological connections. Their findings appear in the Proceedings of the National Academy of Sciences.

The iridescent colors known from peacock feathers or butterfly wings are created by tiny structures that reflect light in a special way. Some bacterial colonies form similar glittering structures.

In collaboration with the Max Planck Institute of Colloids and Interfaces, Leibniz Institute DSMZ-German Collection of Microorganisms and Cell Cultures, Utrecht University, University of Cambridge, and the Netherlands Institute for Sea Research, the scientists sequenced the DNA of 87 structurally colored bacteria and 30 colorless strains and identified genes that are responsible for these fascinating colonies. These findings could lead to the development of environmentally-friendly dyes and materials, a key interest of the collaborating biotechnology company Hoekmine BV.

Scientists have detected the decay of radioactive nuclei by tracking the recoil of dust-sized spheres on which the nuclei were embedded.

Scientists have developed a new way to trap small particles with light. Building on the Nobel Prize winning technique of optical tweezers (Arthur Ashkin, 2018), a team of physicists, led by Dr. David Phillips at the University of Exeter, has advanced the possibilities of optical trapping.

The research paper, published in the journal Science Advances, is titled “Photon-efficient optical tweezers via wavefront shaping.”

Conventional optical tweezers, developed in the 1980s, are a tightly focused laser beam which can attract and trap certain micro-sized particles or organisms, akin to grabbing something with a pair of tweezers.