Toggle light / dark theme

Summary: When the ventral tegmental area was stimulated, monkeys were better able to identify details associated with subconscious visual stimuli they were exposed to.

Source: KU Leuven.

Researchers uncovered for the first time what happens in animals’ brains when they learn from subconscious, visual stimuli. In time, this knowledge can lead to new treatments for a number of conditions.

The debate holds a special interest for neuroscientists; since computer programming has only been around for a few decades, the brain has not evolved any special region to handle it. It must be repurposing a region of the brain normally used for something else.

So late last year, neuroscientists in MIT tried to see what parts of the brain people use when dealing with computer programming. “The ability to interpret computer code is a remarkable cognitive skill that bears parallels to diverse cognitive domains, including general executive functions, math, logic, and language,” they wrote.

Since coding can be learned as an adult, they figured it must rely on some pre-existing cognitive system in our brains. Two brain systems seemed like likely candidates: either the brain’s language system, or the system that tackles complex cognitive tasks such as solving math problems or a crossword. The latter is known as the “multiple demand network.”

With powerful engines, near-photorealistic graphics, and the ability to build incredible, immersive worlds, it’s hard to imagine what the next big technological advance in gaming might be.

Based on a recent tweet by Neuralink co-founder and President Max Hodak, the word might not even apply. In it, he hinted — vaguely, to be fair — that whatever forms of entertainment get programmed into neural implants and brain-computer interfaces will represent a paradigm shift that moves beyond the current terminology.

“We’re gonna need a better term than ‘video game’ once we start programming for more of the sensorium,” Hodak tweeted.

Summary: Study identified 300 “hub genes” that appear to control separate gene networks in brain tissue samples. The SAMD3 gene appears to be a master regulator to control the activity of many of the gene hubs and the genes the hubs control.

Source: UT Southwestern Medical Center.

UT Southwestern scientists have identified key genes involved in brain waves that are pivotal for encoding memories. The findings, published online this week in Nature Neuroscience, could eventually be used to develop novel therapies for people with memory loss disorders such as Alzheimer’s disease and other forms of dementia.

“This is a fascinating study of gut microbiome in older adulthood,” wrote Barbara Bendlin from the University of Wisconsin, Madison. “While the investigators did not look at brain health or cognitive outcomes, it’s interesting to see that they found that healthy aging was accompanied by gut microbiomes that became increasingly more unique to each person starting in middle age. This type of divergence is also observed in brain aging.” (Full comment below.)

Past studies have shown that the gut microbiome undergoes rapid changes in the first three years of life, followed by a longer period of relative stability, then more change once again in later years (Yatsunenko et al., 2012; O’Toole and Jeffery, 2015). Research has also found that centenarians have fewer of the gut microbes commonly seen in younger, healthy people. Instead, they live with an increasingly rarefied microbiota (Kim et al., 2019). This suggests that gut microbiomes become increasingly personalized as people get older, but little is known about how these gut profiles affect the aging process or longevity.

To find out, first author Tomasz Wilmanski and colleagues analyzed gut microbiomes, personal traits, and clinical data from more than 9000 people 18 to 101 years old. They came from three independent cohorts. One was a group of 3653 people aged 18 to 87 who had signed up with Arivale, a now-defunct scientific wellness company co-founded by systems biology pioneer Leroy Hood and Price. Arivale provided personalized wellness coaching by collecting and analyzing data on participants’ genomes and other systems, including their gut microbiomes. Hood founded the Institute for Systems Biology.

One of the major unsolved mysteries of biological science concerns the question of where and in what form information is stored in the brain. I propose that memory is stored in the brain in a mechanically encoded binary format written into the conformations of proteins found in the cell-extracellular matrix (ECM) adhesions that organise each and every synapse. The MeshCODE framework outlined here represents a unifying theory of data storage in animals, providing read-write storage of both dynamic and persistent information in a binary format. Mechanosensitive proteins that contain force-dependent switches can store information persistently, which can be written or updated using small changes in mechanical force. These mechanosensitive proteins, such as talin, scaffold each synapse, creating a meshwork of switches that together form a code, the so-called MeshCODE. Large signalling complexes assemble on these scaffolds as a function of the switch patterns and these complexes would both stabilise the patterns and coordinate synaptic regulators to dynamically tune synaptic activity. Synaptic transmission and action potential spike trains would operate the cytoskeletal machinery to write and update the synaptic MeshCODEs, thereby propagating this coding throughout the organism. Based on established biophysical principles, such a mechanical basis for memory would provide a physical location for data storage in the brain, with the binary patterns, encoded in the information-storing mechanosensitive molecules in the synaptic scaffolds, and the complexes that form on them, representing the physical location of engrams. Furthermore, the conversion and storage of sensory and temporal inputs into a binary format would constitute an addressable read-write memory system, supporting the view of the mind as an organic supercomputer.

I would like to propose here a unifying theory of rewritable data storage in animals. This theory is based around the realisation that mechanosensitive proteins, which contain force-dependent binary switches, can store information persistently in a binary format, with the information stored in each molecule able to be written and/or updated via small changes in mechanical force. The protein talin contains 13 of these switches (Yao et al., 2016; Goult et al., 2018; Wang et al., 2019), and, as I argue here, it is my assertion that talin is the memory molecule of animals. These mechanosensitive proteins scaffold each and every synapse (Kilinc, 2018; Lilja and Ivaska, 2018; Dourlen et al., 2019) and have been considered mainly structural. However, these synaptic scaffolds also represent a meshwork of binary switches that I propose form a code, the so-called MeshCODE.

Human and non-human animal behavior is highly malleable and adapts successfully to internal and external demands. Such behavioral success stands in striking contrast to the apparent instability in neural activity (i.e., variability) from which it arises. Here, we summon the considerable evidence across scales, species, and imaging modalities that neural variability represents a key, undervalued dimension for understanding brain-behavior relationships at inter-and intra-individual levels. We believe that only by incorporating a specific focus on variability will the neural foundation of behavior be comprehensively understood.