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“Badass”. That was the word Harvard University neuroscientist Steve Ramirez used in a Tweet to describe research published online by fellow neuroscientist Ali Güler and colleagues in the journal Nature Neuroscience last March. Güler’s group, based at the University of Virginia in the US, reported having altered the behaviour of mice and other animals by using a magnetic field to remotely activate certain neurons in their brains. For Ramirez, the research was an exciting step forward in the emerging field of “magnetogenetics”, which aims to use genetic engineering to render specific regions of the brain sensitive to magnetism – in this case by joining proteins containing iron with others that control the flow of electric current through nerve-cell membranes.

By allowing neurons deep in the brain to be switched on and off quickly and accurately as well as non-invasively, Ramirez says that magnetogenetics could potentially be a boon for our basic understanding of behaviour and might also lead to new ways of treating anxiety and other psychological disorders. Indeed, biologist Kenneth Lohmann of the University of North Carolina in the US says that if the findings of Güler and co-workers are confirmed then magnetogenetics would constitute a “revolutionary new tool in neuroscience”

The word “if” here is important. In a paper posted on the arXiv preprint server in April last year and then published in a slightly revised form in the journal eLife last August, physicist-turned-neuroscientist Markus Meister of the California Institute of Technology laid out a series of what he describes as “back-of-the-envelope” calculations to check the physical basis for the claims made in the research. He did likewise for an earlier magnetogenetics paper published by another group in the US as well as for research by a group of scientists in China positing a solution to the decades-old problem of how animals use the Earth’s magnetic field to navigate – papers that were also published in Nature journals.

On this episode, neuroscientist and author Robert Sapolsky joins Nate to discuss the structure of the human brain and its implication on behavior and our ability to change. Dr. Sapolsky also unpacks how the innate quality of a biological organism shaped by evolution and the surrounding environment — meaning all animals, including humans — leads him to believe that there is no such thing as free will, at least how we think about it today. How do our past and present hormone levels, hunger, stress, and more affect the way we make decisions? What implications does this have in a future headed towards lower energy and resource availability? How can our species manage the mismatch of our evolutionary biology with our modern day challenges — and navigate through a ‘determined’ future?

About Robert Sapolsky:

Robert Sapolsky is professor of biology and neurology at Stanford University and a research associate with the Institute of Primate Research at the National Museum of Kenya. Over the past thirty years, he has divided his time between the lab, where he studies how stress hormones can damage the brain, and in East Africa, where he studies the impact of chronic stress on the health of baboons. Sapolsky is author of several books, including Why Zebras Don’t Get Ulcers, A Primate’s Memoir, Behave: The Biology of Humans at Our Best and Worst, and his newest book coming out in October, Determined: Life Without Free Will. He lives with his family in San Francisco.

For Show Notes and More visit: https://www.thegreatsimplification.co

00:00 — Episode highlight.
00:15 — Guest introduction.
03:10 — When did Robert know he wanted to study animal behavior?
04:40 — When was his last research trip?
05:46 — Challenges that come from differences from modern and ancestral environments.
07:20 — Physiology and our emotions.
09:37 — Divide in evolutionary beliefs.
12:13 — Behavioral science and religion.
14:40 — Past students’ impacted by Robert.
16:48 — Testosterone.
21:07 — Dopamine.
29:02 — Oxytocin.
32:19 — Hormones affecting social behavior.
38:21 — Changing the environmental stimuli of pregnant people to positively impact fetus’ development.
41:55 — Free will.
57:24 — Science of attractiveness.
58:55 — Do people have free will?
1:13:12 — Emergence.
1:18:17 — Quantum and indeterminacy.
1:19:18 — Complexity of free will.
1:23:46 — Difference between free will and agency.
1:26:43 — How to use Robert’s work to change policies around the world in a positive way.
1:29:15 — What’s the difference between a deterministic world and a fatalistic one?
1:34:39 — Robert’s thoughts on his newest book, Determined: Life Without Free Will.
1:40:48 — Key components in a new systems society understanding this science.
1:45:30 — What should listeners take away from this podcast?
1:47:32 — Robert’s recommendations for the polycrisis.
1:52:20 — What Robert cares most about in the world.
1:53:00 — Robert’s magic wand.
1:54:36 — Future topics of conversations.

#natehagens #thegreatsimplification #neuroscience #dopamine #freewill #testosterone

In a world where choices seem endless, could it be that our ‘free will’ is nothing more than an illusion?

When it comes to things like choosing a morning run over an extra hour of sleep, opting for an apple instead of that enticing pint of ice cream, or quitting your job on a whim…

…What’s truly guiding these decisions? Is it willpower, biology, environment, or perhaps a unique strength of character we’ve built over time?

Or… could it be something else entirely, something beyond our control?

Here’s where our guest, Dr. Robert Sapolsky — a renowned Professor of Biology, Neurology and Neurosurgery at Stanford University — offers us a slightly unsettling, yet eye-opening, perspective.

He suggests that every decision we make — from the podcasts we tune into, to judges making a case verdict, to choosing our life partner — isn’t shaped by any sort of conscious control or free will. Instead, he believes our actions are driven by factors beyond our grasp and influence.

Scientists in China have managed to revive brain activity in pigs nearly an hour after circulation ceased, thanks to the surprising involvement of the liver.

If translatable to humans, this finding could have significant implications for extending the critical window in which doctors can resuscitate patients following sudden cardiac arrest.

The research team, led by Dr. Xiaoshun He at Sun Yat-Sen University, experimented with the brains of 17 Tibetan minipigs to investigate how the liver might influence brain recovery.

Researchers at REMspace, a startup based in California, have reported that two people were able to communicate in their dreams.

The experiment is an example of the potential that lucid dreams have to create new communication methods, pushing the limits of what scientists thought humans were capable of.

The company claimed that two individuals managed to induce lucid dreams with success and shared a simple message using specially designed equipment.

Researchers connecting pieces of the massive Alzheimer’s puzzle are closer to slotting the next one in place, with yet another link between our guts and brain.

Animal studies have demonstrated Alzheimer’s can be passed on to young mice through a transfer of gut microbes, confirming a link between the digestive system and the health of the brain.

A 2023 study adds further support to the theory that inflammation could be the mechanism through which this occurs.

Richard Scolyer was fully engaged in the business of living when he suddenly received a death sentence. A person more alive would be hard to find. As an endurance athlete competing across the globe, he was in peak physical condition. As one of the world’s leading pathologists on melanoma whose pioneering research has saved thousands of lives, he was in demand. At 56, Prof Richard Scolyer was flying along. His life, he says, was “rich”. And then, on the morning of 20 May 2023, he found himself losing consciousness and convulsing on the floor in a hotel room in Poland, panicking and scared.

After this grand mal seizure, he went for an MRI scan at University hospital in Krakow. It found a mass in his temporal lobe. Scolyer knew immediately it had delivered very bad news.

Related: When I found out about the brain tumour that would kill me, I faced my worst fears – but I chose to take it on.