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Cognitive flexibility, the brain’s ability to switch between different rules or action plans depending on the context, is key to many of our everyday activities. For example, imagine you’re driving on a highway at 65 miles per hour. When you exit onto a local street, you realize that the situation has changed and you need to slow down.
When we move between different contexts like this, our brain holds multiple sets of rules in mind so that it can switch to the appropriate one when necessary. These neural representations of task rules are maintained in the prefrontal cortex, the part of the brain responsible for planning action.
A new study from MIT has found that a region of the thalamus is key to the process of switching between the rules required for different contexts. This region, called the mediodorsal thalamus, suppresses representations that are not currently needed. That suppression also protects the representations as a short-term memory that can be reactivated when needed.
It seems like a way to toggle between irrelevant and relevant contexts, and one advantage is that it protects the currently irrelevant representations from being overwritten
says Michael Halassa an assistant professor of brain and cognitive sciences and a member of MIT’s McGovern Institute for Brain Research.
Halassa is the senior author of the paper. The paper’s first author is former MIT graduate student Rajeev Rikhye, who is now a postdoc in Halassa’s lab. Aditya Gilra, a postdoc at the University of Bonn, is also an author.

Cognitive Flexibility
Previous studies have found that the prefrontal cortex is essential for cognitive flexibility, and that a part of the thalamus called the mediodorsal thalamus also contributes to this ability.
In a 2017 study published in Nature, Halassa and his colleagues showed that the mediodorsal thalamus helps the prefrontal cortex to keep a thought in mind by temporarily strengthening the neuronal connections in the prefrontal cortex that encode that particular thought.
In the new study, Halassa wanted to further investigate the relationship between the mediodorsal thalamus and the prefrontal cortex. To do that, he created a task in which mice learn to switch back and forth between two different contexts, one in which they must follow visual instructions and one in which they must follow auditory instructions.
In each trial, the mice are given both a visual target (flash of light to the right or left) and an auditory target (a tone that sweeps from high to low pitch, or vice versa). These targets offer conflicting instructions. One tells the mouse to go to the right to get a reward; the other tells it to go left. Before each trial begins, the mice are given a cue that tells them whether to follow the visual or auditory target.
The only way for the animal to solve the task is to keep the cue in mind over the entire delay, until the targets are given Halassa says.

Mediodorsal Thalamus
The researchers found that thalamic input is necessary for the mice to successfully switch from one context to another. When they suppressed the mediodorsal thalamus during the cuing period of a series of trials in which the context did not change, there was no effect on performance.
However, if they suppressed the mediodorsal thalamus during the switch to a different context, it took the mice much longer to switch.
By recording from neurons of the prefrontal cortex, the researchers found that when the mediodorsal thalamus was suppressed, the representation of the old context in the prefrontal cortex could not be turned off, making it much harder to switch to the new context.
In addition to helping the brain switch between contexts, this process also appears to help maintain the neural representation of the context that is not currently being used, so that it doesn’t get overwritten, Halassa says. This allows it to be activated again when needed. The mice could maintain these representations over hundreds of trials, but the next day, they had to relearn the rules associated with each context.
Sabine Kastner a professor of psychology at the Princeton Neuroscience Institute, described the study as a major leap forward in the field of cognitive neuroscience.
This is a tour-de-force from beginning to end, starting with a sophisticated behavioral design, state-of-the-art methods including causal manipulations, exciting empirical results that point to cell-type specific differences and interactions in functionality between thalamus and cortex, and a computational approach that links the neuroscience results to the field of artificial intelligence says Kastner, who was not involved in the research.

Multitasking AI
The findings could help guide the development of better artificial intelligence algorithms, Halassa says. The human brain is very good at learning many different kinds of tasks, singing, walking, talking, etc.
However, neural networks (a type of artificial intelligence based on interconnected nodes similar to neurons) usually are good at learning only one thing. These networks are subject to a phenomenon called catastrophic forgetting, when they try to learn a new task, previous tasks become overwritten.
Halassa and his colleagues now hope to apply their findings to improve neural networks’ ability to store previously learned tasks while learning to perform new ones.
The research was funded by the National Institutes of Health, the Brain and Behavior Foundation, the Klingenstein Foundation, the Pew Foundation, the Simons Foundation, the Human Frontiers Science Program, and the German Ministry of Education.

autumn pastel

Planet Earth working on 3 Mars landers to follow InSight - As Mars' newest resident settles in, Planet Earth is working on three more landers and at least two orbiters to join the scientific Martian brigade.

Caesar, the old lion that died this year in Artis

He died of old age. This photo was made in April this year. He was 20.

A photo part of a blog on my website: Really close-up!
https://anjawessels.photography/really-close-up/

*Please follow me on my website: www.anjawessels.photograhy *

CAMERA: Canon EOS 650D
LENS: Tamron 70-300mm

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#photography #photo #lion #cat #caturday #artis #bigcat #king #caesar

Pokemon director Junichi Masuda has reiterated the company’s stance that the Pokemon: Let’s GO, Pikachu and Eevee! games are what he describes as “core” titles. Mr. Masuda also stated that other Pokemon games for the Nintendo Switch could connect to the…

New York City, 42nd Street.

The light was just perfect to get the Brick color in the air.

Enjoy

https://film-book.com/news-brief-daredevil-tv-show-cancelled-preacher-renewed-blue-beetle-movie-being-developed-more/

Yankees could see Robertson and Britton go to Red Sox https://nyp.st/2E7FbiO

How Trump's bashing of The New York Times and CNN has benefited all

A new machine-learning technique mimics the brain’s ability to adapt to new circumstances.

https://rxscience.org/artificial-intelligence-is-learning-to-keep-learning/

Don't Miss Out! Crescent Moon, Venus & Virgo's Brightest Star, Spica Before Sunrise

On December 2 up to 4, wake up before dawn to see Venus and the crescent Moon. Venus appears near to Spica, Virgo's brilliantly white star.

This month presents a fine time for watching Venus' crescent phase through a telescope. On December 2, 2018 the bright planet Venus reaches its greatest illuminated extent.

Right now, Venus' disk is about 25& illuminated by sunshine.

On Dec. 3 the crescent Moon will be close to Venus and Spica forming a celestial triangle.
https://earthsky.org/tonight/moon-venus-at-dawn-december-2-to-4

Have a nice month and Clear Skies Everyone!

Clips, images credit: nemesis maturity own work, NASA/JPL

Music credit: YouTube Audio Library

Samsung Galaxy S10 will be the most innovative phones in recent years.

The art of the wilderness

Bill Kristol@BillKristol

15 mins ago

This thread on Michael Cohen’s sentencing submission is very much worth reading. https://twitter.com/renato_mariotti/status/1068786624606101504

Doctors are learning that one of the best ways to fight disease and illness is by avoiding the very foods that cause chronic inflammation. While this isn’t a new concept for those with a more holistic view of the body, it is for the modern medical system, which focuses on treating symptoms instead of addressing the root cause of an issue

#inflammation #food #healthyfood
https://avrialszone.blogspot.com

George H W Bush has passed away at 94 years old .. condolences to his family and friends . He is now back with Barbara for eternity

Alexandria Ocasio-Cortez Leads Opposition to Coal Puppet Joe Manchin for Top Senate Energy Slot https://theintercept.com/2018/11/30/alexandria-ocasio-cortez-leads-opposition-to-coal-puppet-joe-manchin-for-top-senate-energy-slot/ -via Flynx

I saw this on the BBC and thought you should see it:

ShareChat: India’s homegrown rival to WhatsApp - http://www.bbc.co.uk/news/world-asia-india-46341633

With more than 60 satellites jammed in for the ride, a Falcon 9 rocket will get used a third time, fulfilling one of Elon Musk's standing promises. https://wrd.cm/2Rs8I9T

Gmail Common Errors and Their Solutions #google #gmail #news