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During deliberation, as we quietly consider our options, the neural activities representing the decision variables that reflect the goodness of each option rise in various regions of the cerebral cortex.1,2,3,4,5,6,7 If the options are depicted visually, we make saccades, focusing gaze on each option. Do the kinematics of these saccades reflect the state of the decision variables? To test this idea, we engaged human participants in a decision-making task in which they considered two effortful options that required walking across various distances and inclines. As they deliberated, they made saccades between the symbolic representations of their options. These deliberation period saccades had no bearing on the effort they would later expend, yet saccade velocities increased gradually and differentially: the rate of rise was faster for saccades toward the option that they later indicated as their choice. Indeed, the rate of rise encoded the difference in the subjective value of the two options. Importantly, the participants did not reveal their choice at the conclusion of deliberation, but rather waited during a delay period, and finally expressed their choice by making another saccade. Remarkably, vigor for this saccade dropped to baseline and no longer encoded subjective value. Thus, saccade vigor appeared to provide a real-time window to the otherwise hidden process of option evaluation during deliberation.

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David Chalmers is a professor of philosophy and neural science at New York University, and an honorary professor of philosophy at the Australian National University. He is the co-director of the Center for Mind, Brain, and Consciousness, as well as the PhilPapers Foundation. His research focuses on the philosophy of mind, especially consciousness, and its connection to fields such as cognitive science, physics, and technology. He also investigates areas such as the philosophy of language, metaphysics, and epistemology. With his impressive breadth of knowledge and experience, David Chalmers is a leader in the philosophical community.

The central challenge for consciousness studies is to explain how something immaterial, subjective, and personal can arise out of something material, objective, and impersonal. This is illustrated by the example of a bat, whose sensory experience is much different from ours, making it difficult to imagine what it’s like to be one. Thomas Nagel’s “inconceivability argument” has its advantages and disadvantages, but ultimately it is impossible to solve the mind-body problem due to the subjective nature of experience. This is further explored by examining the concept of philosophical zombies, which are physically and behaviorally indistinguishable from conscious humans yet lack conscious experience. This has implications for the Hard Problem of Consciousness, which is the attempt to explain how mental states are linked to neurophysiological activity. The Chinese Room Argument is used as a thought experiment to explain why physicality may be insufficient to be the source of the subjective, coherent experience we call consciousness. Despite much debate, the Hard Problem of Consciousness remains unsolved. Chalmers has been working on a functional approach to decide whether large language models are, or could be conscious.

Filmed at #neurips22

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A large portion of people on the planet is infected with the parasite Toxoplasma. Now, a study headed by scientists at Stockholm University demonstrates how this tiny parasite spreads so successfully throughout the body, for example to the brain. The parasite infects immune cells and hijacks their identity. The research was recently published in the journal Cell Host & Microbe.

The various roles of immune cells in the body are very strictly regulated in order to combat infections. How Toxoplasma infects so many people and animal species and spreads so quickly has long been a mystery to scientists.

“We have now discovered a protein that the parasite uses to reprogram the immune system”, says Arne ten Hoeve, a researcher at the Department of Molecular Biosciences, Wenner-Gren Institute at Stockholm University.

Researchers discovered a new daily rhythm in a kind of synapse that dampens brain activity using a mouse model. These neural connections, known as inhibitory synapses, are rebalanced as we sleep to allow us to consolidate new information into lasting memories. The results, which were published in the journal PLOS Biology, may help explain how subtle synaptic changes improve memory in humans. Researchers from the National Institute of Neurological Disorders and Stroke (NINDS), which is part of the National Institutes of Health, led the study.

“Inhibition is important for every aspect of brain function. But for over two decades, most sleep studies have focused on understanding excitatory synapses,” said Dr. Wei Lu, senior investigator at NINDS. “This is a timely study to try to understand how sleep and wakefulness regulate the plasticity of inhibitory synapses.”

Kunwei Wu, Ph.D., a postdoctoral fellow in Dr. Lu’s lab, investigated what occurs at inhibitory synapses in mice during sleep and wakefulness. Electrical recordings from neurons in the hippocampus, a brain region involved in memory formation, revealed a previously unknown pattern of activity. During wakefulness, steady “tonic” inhibitory activity increased but fast “phasic” inhibition decreased. They also discovered a far larger activity-dependent enhancement of inhibitory electrical responses in awake mouse neurons, suggesting that wakefulness, rather than sleep, might strengthen these synapses to a greater extent.

Will there ever be a time when the human brain and its cognitive abilities will be replaced by a computer.

Can the forms of calculations that are found in a computer be able to go beyond the capacity of the neurons that are found in our own brains.

The age of singularity is where the human brain will be replaced by computers people like elon musk & Ray Kurzweil believe because of technology the future will be a heaven like civilization.

#singularity #technology #science #sciencefacts

Imagine brain implants that let you control devices by thought alone—or let computers read your mind. It’s early days, but research into this technology is well under way.

Film supported by @mishcondereya.

00:00 — Are brain implants the future of computing?
00:58 — Headsets are changing how brains interact with the virtual world.
02:24 — What is a brain computer interface?
03:24 — What’s holding this technology back?
04:00 — How wearable BCIs can read your mind.
06:27 — How BCIs physically alter the brain.
07:17 — Invasive brain implants.
09:14 — The first human cyborg.
09:51 — What’s next?

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What does a brain-computer interface feel like? https://econ.st/3z07haD