Introducing the brain: strange brain tendrils (Introduction)

by David Turell , Saturday, December 03, 2022, 21:53 (719 days ago) @ David Turell

A new mouse finding:

https://www.sciencealert.com/mysterious-tendrils-inside-the-brain-may-control-our-perce...

"Tiny antenna-like organelles once thought to be holdovers from our ancient past appear to play a crucial role in keeping track of time, according to a recent study on mice by researchers from the University of California, Irvine (UCI), in the US.

"Known as cilia, the microtubule projections can be found throughout the more complex branches of the tree of life, including on many of our own cells.

"Where they often have a role in motion, either pushing cells around or moving materials close to their surface, most in the human body – described as primary cilia – are non-motile.

Initial investigations more than a century ago considered these kinds of structures to be vestigial. Today, many primary cilia are recognized as part of a signaling hub system that keeps the body adapting and responding appropriately.

***

"For their study, the researchers used a gene manipulation technique to remove striatum cilia in mice, which had a dramatic effect.

"While the mice could still maintain long-term memories and habitual or already learned motor skills, various negative effects were observed after the cilia removal.

"The rodents proved unable to learn new motor tasks and showed repetitive motor behavior as well as noticeable delays in making decisions. Their ability to quickly recall location and orientation information, and their ability to filter out irrelevant environmental sensory information, were negatively affected.

***

"'Successful performance of working memory, attention, decision-making and executive function requires accurate and precise timing judgment, usually within a millisecond to a minute," says UCI neuroscientist Amal Alachkar.

"'When that capacity is impaired, it means losing the ability to quickly adjust behavior in response to changes in external stimuli and failing to sustain appropriate, goal-oriented motor responses."

"It's clear that all the impacts of cilia removal have a shared characteristic: the loss of ability to quickly change behavior in response to changes in the environment in an appropriate time frame.

"How the results of this study relate to humans isn't yet fully known, but it's likely that the human brain's cilia work in a similar way to those in mice."

Comment: These functions are automatic in fully functional brains and underlie/are triggered by decision making in the frontal cortex. It is not surprising the brain has 80-100 billion neurons. but also has billions of functional astrocytes and now these cilia. Not by chance.