Brain Inspired

Support the show to get full episodes, full archive, and join the Discord community. The Transmitter is an online publication that aims to deliver useful information, insights and tools to build bridges across neuroscience and advance research. Visit thetransmitter.org to explore the latest neuroscience news and perspectives, written by journalists and scientists. Read more about our partnership. Sign up for Brain Inspired email alerts to be notified every time a new Brain Inspired episode is released. To explore more neuroscience news and perspectives, visit thetransmitter.org. Cristopher Moore is a professor at the Santa Fe Institute in New Mexico, and he is a computation and computational complexity expert. He recently joined a us in my complexity discussion group, and answered a bunch of our questions, but I wasn't done with him regarding what, if anything, computational complexity has to do understanding how brains and minds work. So that's why he's here today, and we discuss a wide variety of topics related to AI, computation, computational complexity, and cognition. Cris's Homepage Book: The Nature of Computation Related papers What Is a Macrostate? Subjective Observations and Objective Dynamics 0:00 - Intro 4:24 - The Nature of Computation 9:14 - Computational complexity 28:22 - Real mathematics 35:08 - Current state of AI 39:04 - Computational complexity in the AI world 47:53 - Cognition, creation, problems 56:16 - Rugged landscapes and generalization 1:13:52 - What is computation? 1:32:31 - How would you study the brain?

Support the show to get full episodes, full archive, and join the Discord community. The Transmitter is an online publication that aims to deliver useful information, insights and tools to build bridges across neuroscience and advance research. Visit thetransmitter.org to explore the latest neuroscience news and perspectives, written by journalists and scientists. Read more about our partnership. Sign up for Brain Inspired email alerts to be notified every time a new Brain Inspired episode is released. To explore more neuroscience news and perspectives, visit thetransmitter.org. Tatiana Engel runs the Engel lab at Princeton University in the Princeton Neuroscience Institute. She's also part of the International Brain Laboratory, a massive across-lab, across-world, collaboration which you'll hear more about. My main impetus for inviting Tatiana was to talk about two projects she's been working on. One of those is connecting the functional dynamics of cognition with the connectivity of the underlying neural networks on which those dynamics unfold. We know the brain is high-dimensional - it has lots of interacting connections, we know the activity of those networks can often be described by lower-dimensional entities called manifolds, and Tatiana and her lab work to connect those two processes with something they call latent circuits. So you'll hear about that, you'll also hear about how the timescales of neurons across the brain are different but the same, why this is cool and surprising, and we discuss many topics around those main topics.  Engel Lab. @engeltatiana.bsky.social. International Brain Laboratory. Related papers: Latent circuit inference from heterogeneous neural responses during cognitive tasks The dynamics and geometry of choice in the premotor cortex. A unifying perspective on neural manifolds and circuits for cognition Brain-wide organization of intrinsic timescales at single-neuron resolution Single-unit activations confer inductive biases for emergent circuit solutions to cognitive tasks. 0:00 - Intro 3:03 - No central executive 5:01 - International brain lab 15:57 - Tatiana's background 24:49 - Dynamical systems 17:48 - Manifolds 33:10 - Latent task circuits 47:01 - Mixed selectivity 1:00:21 - Internal and external dynamics 1:03:47 - Modern vs classical modeling 1:14:30 - Intrinsic timescales 1:26:05 - Single trial dynamics 1:29:59 - Future of manifolds

Support the show to get full episodes, full archive, and join the Discord community. The Transmitter is an online publication that aims to deliver useful information, insights and tools to build bridges across neuroscience and advance research. Visit thetransmitter.org to explore the latest neuroscience news and perspectives, written by journalists and scientists. Read more about our partnership. Sign up for Brain Inspired email alerts to be notified every time a new Brain Inspired episode is released. To explore more neuroscience news and perspectives, visit thetransmitter.org. My guest today is Dan Nicholson, Assistant Professor of Philosophy at George Mason University, here to talk about his little book, What Is Life? Revisited. Erwin Schrödinger's What Is Life is a famous book that people point to as having predicted DNA and influenced and inspired many well-known biologists ushering in the molecular biology revolution. But Schrödinger was a physicist, not a biologist, and he spent very little time and effort toward understanding biology. What was he up to, why did he write this "famous little book"? Schrödinger had an agenda, a physics agenda. He wanted to save the older deterministic version of quantum physics from the new indeterministic version. When Dan was on the podcast a few years ago, we talked about the machine view of biological systems, how everything has become a "mechanism", and how that view fails to capture what modern science is actually telling us, that organisms are unlike machines in important ways. That work of Dan's led him down this path to Schrödinger's What Is Life, which he argues was a major contributor to that machine metaphor so ubiquitous today in biology. One of the reasons I'm interested in this kind of work is because the cognitive sciences, including neuroscience and artificial intelligence, inherited this mechanistic perspective, and swallowed it so hard that if you don't include the word "mechanism" in your research paper, you're vastly decreasing your chances of getting your work published, when in fact the mechanistic perspective is one super useful perspective among many. Dan’s website. Google Scholar. Social: @NicholsonHPBio; @djnicholson.bsky.social What Is Life? Revisited Previous episode: BI 150 Dan Nicholson: Machines, Organisms, Processes Read the transcript. 0:00 - Intro 7:27 - Why Schrodinger wrote What is Life 15:13 - Aperiodic crystal and the meaning of code 21:39 - Order-from-order, order-from-disorder 28:32 - Appeal to authority 37:48 - Cell as machine 39:33 - Relation between DNA and organism (development) 44:44 - Negentropy 53:54 - Original contributions 58:54 - Mechanistic metaphor in neuroscience 1:16:05 - What's the lesson? 1:28:06 - Historical sleuthing 1:39:49 - Modern philosophy of biology

Support the show to get full episodes, full archive, and join the Discord community. The Transmitter is an online publication that aims to deliver useful information, insights and tools to build bridges across neuroscience and advance research. Visit thetransmitter.org to explore the latest neuroscience news and perspectives, written by journalists and scientists. Read more about our partnership. Sign up for Brain Inspired email alerts to be notified every time a new Brain Inspired episode is released. To explore more neuroscience news and perspectives, visit thetransmitter.org. Nikolay Kukushkin is an associate professor at New York University, and a senior scientist at Thomas Carew’s laboratory at the Center for Neural Science. He describes himself as a "molecular philosopher", owing to his day job as a molecular biologist and his broad perspective on how it "hangs together", in the words of Wilfrid Sellers, who in 1962 wrote, “The aim of philosophy, abstractly formulated, is to understand how things in the broadest possible sense of the term hang together in the broadest possible sense of the term”. That is what Niko does in his book One Hand Clapping: Unraveling the Mystery of the Human Mind. This book is about essences across spatial scales in nature. More precisely, it's about giving names to what is fundamental, or essential, to how things and processes function in nature. Niko argues those essences are where meaning resides. That's very abstract, and we'll spell it out more during the discussion. But as an example at the small scale, the essences of carbon and oxygen, respectively, are creation and destruction, which allows metabolism to occur in biological organisms. Moving way up the scale, following this essence perspective leads Niko to the conclusion that there is no separation between our minds and the world, and that instead we should embrace the relational aspect of mind and world as a unifying principle. On the way, via evolution, we discuss many more examples, plus some of his own work studying how memory works in individual cells, not just neurons or populations of neurons in brains. Niko's website. Twitter: @niko_kukushkin. Book: One Hand Clapping: Unraveling the Mystery of the Human Mind Read the transcript. 0:00 - Intro 9:28 - Studying memory in cells 10:14 - Who the book is for 17:57 - Studying memory in cells 21:53 - What is memory? 29:49 - Book 29:52 - How the book came about 37:56 - Central message of the book 44:07 - Meaning in nature 49:09 - Meaning and essence 51:55 - Multicellularity and ant colonies 57:43 - Eukaryotes and complexification 1:03:38 - Why do we have brains? 1:06:17 - Emergence 1:10:58 - Language 1:12:41 - Human evolution 1:14:41 - Artificial intelligence, meaning and essences 1:25:49 - Consciousness

Support the show to get full episodes, full archive, and join the Discord community. The Transmitter is an online publication that aims to deliver useful information, insights and tools to build bridges across neuroscience and advance research. Visit thetransmitter.org to explore the latest neuroscience news and perspectives, written by journalists and scientists. Read more about our partnership: https://www.thetransmitter.org/partners/ Sign up for the “Brain Inspired” email alerts to be notified every time a new “Brain Inspired” episode is released: https://www.thetransmitter.org/newsletters/ To explore more neuroscience news and perspectives, visit thetransmitter.org. What changes and what stays the same as you scale from single neurons up to local populations of neurons up to whole brains? How tuning parameters like the gain in some neural populations affects the dynamical and computational properties of the rest of the system. Those are the main questions my guests today discuss. Michael Breakspear is a professor of Systems Neuroscience and runs the Systems Neuroscience Group at the University of Newcastle in Australia. Mac Shine is back, he was here a few years ago. Mac runs the Shine Lab at the University of Sidney in Australia. Michael and Mac have been collaborating on the questions I mentioned above, using a systems approach to studying brains and cognition. The short summary of what they discovered in their first collaboration is that turning up or down the gain across broad networks of neurons in the brain affects integration - working together - and segregation - working apart. They map this gain modulation on to the ascending arousal pathway, in which the locus coeruleus projects widely throughout the brain distributing noradrenaline. At a certain sweet spot of gain, integration and segregation are balanced near a bifurcation point, near criticality, which maximizes properties that are good for cognition. In their recent collaboration, they used a coarse graining procedure inspired by physics to study the collective dynamics of various sizes of neural populations, going from single neurons to large populations of neurons. Here they found that despite different coding properties at different scales, there are also scale-free properties that suggest neural populations of all sizes, from single neurons to brains, can do cognitive stuff useful for the organism. And they found this is a conserved property across many different species, suggesting it's a universal principle of brain dynamics in general. So we discuss all that, but to get there we talk about what a systems approach to neuroscience is, how systems neuroscience has changed over the years, and how it has inspired the questions Michael and Mac ask. Breakspear: Systems Neuroscience Group. @DrBreaky. Shine: Shine Lab. @jmacshine. Related papers Dynamic models of large-scale brain activity Metastable brain waves The modulation of neural gain facilitates a transition between functional segregation and integration in the brain Multiscale Organization of Neuronal Activity Unifies Scale-Dependent Theories of Brain Function. The brain that controls itself. Metastability demystified — the foundational past, the pragmatic present and the promising future. Generation of surrogate brain maps preserving spatial autocorrelation through random rotation of geometric eigenmodes. Related episodes BI 212 John Beggs: Why Brains Seek the Edge of Chaos BI 216 Woodrow Shew and Keith Hengen: The Nature of Brain Criticality BI 121 Mac Shine: Systems Neurobiology Read the transcript. 0:00 - Intro 4:28 - Neuroscience vs neurobiology 8:01 - Systems approach 26:52 - Physics for neuroscience 33:15 - Gain and bifurcation: earliest collaboration 55:32 - Multiscale organization 1:17:54 - Roadblocks

Support the show to get full episodes, full archive, and join the Discord community. We are in an exciting time in the cross-fertilization of the neurotech industry and the cognitive sciences. My guest today is Chris Rozell, who sits in that space that connects neurotech and brain research. Chris runs the Structured Information for Precision Neuroengineering Lab at Georgia Tech University, and he was just named the inaugural director of Georgia Tech’s Institute for Neuroscience, Neurotechnology, and Society. I think this is the first time on brain inspired we've discussed stimulating brains to treat mental disorders. I think. Today we talk about Chris's work establishing a biomarker from brain recordings of patients with treatment resistant depression, a specific form of depression. These are patients who have deep brain stimulation electrodes implanted in an effort to treat their depression. Chris and his team used that stimulation in conjunction with brain recordings and machine learning tools to predict how effective the treatment will be under what circumstances, and so on, to help psychiatrists better treat their patients. We'll get into the details and surrounding issues. Toward the end we also talk about Chris's unique background and path and approach, and why he thinks interdisciplinary research is so important. He's one of the most genuinely well intentioned people I've met, and I hope you're inspired by his research and his story. Structured Information for Precision Neuroengineering Lab. Twitter: @crozSciTech. Related papers Cingulate dynamics track depression recovery with deep brain stimulation. Story Collider: Wired Lives 0:00 - Intro 3:20 - Overview of the study 17:11 - Closed and open loop stimulation 19:34 - Predicting recovery 28:45 - Control knob for treatment 39:04 - Historical and modern brain stimulation 49:07 - Treatment resistant depression 53:44 - Control nodes complex systems 1:01:06 - Explainable generative AI for a biomarker 1:16:40 - Where are we and what are the obstacles? 1:21:32 - Interface Neuro 1:24:55 - Why Chris cares Read the transcript.

Support the show to get full episodes, full archive, and join the Discord community. The Transmitter is an online publication that aims to deliver useful information, insights and tools to build bridges across neuroscience and advance research. Visit thetransmitter.org to explore the latest neuroscience news and perspectives, written by journalists and scientists. Read more about our partnership. Sign up for Brain Inspired email alerts to be notified every time a new Brain Inspired episode is released. To explore more neuroscience news and perspectives, visit thetransmitter.org. A few episodes ago, episode 212, I conversed with John Beggs about how criticality might be an important dynamic regime of brain function to optimize our cognition and behavior. Today we continue and extend that exploration with a few other folks in the criticality world. Woodrow Shew is a professor and runs the Shew Lab at the University of Arkansas. Keith Hengen is an associate professor and runs the Hengen Lab at Washington University in St. Louis Missouri. Together, they are Hengen and Shew on a recent review paper in Neuron, titled Is criticality a unified setpoint of brain function? In the review they argue that criticality is a kind of homeostatic goal of neural activity, describing multiple properties and signatures of criticality, they discuss multiple testable predictions of their thesis, and they address the historical and current controversies surrounding criticality in the brain, surveying what Woody thinks is all the past studies on criticality, which is over 300. And they offer a account of why many of these past studies did not find criticality, but looking through a modern lens they most likely would. We discuss some of the topics in their paper, but we also dance around their current thoughts about things like the nature and implications of being nearer and farther from critical dynamics, the relation between criticality and neural manifolds, and a lot more. You get to experience Woody and Keith thinking in real time about these things, which I hope you appreciate. Shew Lab. @ShewLab Hengen Lab. Is criticality a unified setpoint of brain function? Read the transcript. 0:00 - Intro 3:41 - Collaborating 6:22 - Criticality community 14:47 - Tasks vs. Naturalistic 20:50 - Nature of criticality 25:47 - Deviating from criticality 33:45 - Sleep for criticality 38:41 - Neuromodulation for criticality 40:45 - Criticality Definition part 1: scale invariance 43:14 - Criticality Definition part 2: At a boundary 51:56 - New method to assess criticality 56:12 - Types of criticality 1:02:23 - Value of criticality versus other metrics 1:15:21 - Manifolds and criticality 1:26:06 - Current challenges