Why is Facebook (Meta) harassing my account?
Decision on case of ex-Facebook moderator, who claims the work left him with PTSD, hailed as win for accountability of big tech in Africa.
Category: neuroscience – Page 243
Continuous neural control of a bionic limb restores biomimetic gait after amputation
In this study we show that residual muscle–tendon afferents enable a person with transtibial amputation to directly neuromodulate biomimetic locomotion, enabling neuroprosthetic adaptations to varying walking speeds, terrains and perturbations. Such versatile and biomimetic gait has not been attainable in contemporary bionic legs without the reliance upon predefined intrinsic control frameworks1,2. Central to the improved neural controllability demonstrated in this study are muscle–tendon sensory organs26,27 that deliver proprioceptive afferents. The surgically reconstructed, agonist–antagonist muscles emulate natural agonistic contraction and antagonistic stretch, thereby generating proprioceptive afferents corresponding to residual muscle movements.
During the ground contact phase of walking, the reconstructed muscle–tendon dynamics of the AMI do not precisely emulate intact biological muscle dynamics. The residual muscles of the AMI contract and stretch freely within the amputated residuum, only pulling against one another and not against the external environment. In distinction, for intact biological limbs, the muscle–tendons span the ankle joint, exerting large forces through an interaction with the external environment. These interactive muscle–tendon dynamics in intact biological limbs are believed to play a critical role in spinal reflexes, in addition to providing feedback for volitional motor control12. Therefore, for this study, the demonstrated capacity of augmented afferents to enable biomimetic gait neuromodulation is surprising given that their total magnitude is largely reduced compared with those of intact biological limbs26,27,45,46.
Key mechanisms identified for regeneration of neurons
Neurological disorders, such as trauma, stroke, epilepsy, and various neurodegenerative diseases, often lead to the permanent loss of neurons, causing significant impairments in brain function. Current treatment options are limited, primarily due to the challenge of replacing lost neurons.
Direct neuronal reprogramming, a complex procedure that involves changing the function of one type of cell into another, offers a promising strategy.
In cell culture and in living organisms, glial cells—the non-neuronal cells in the central nervous system—have been successfully transformed into functional neurons. However, the processes involved in this reprogramming are complex and require further understanding. This complexity presents a challenge, but also a motivation, for researchers in the field of neuroscience and regenerative medicine.
Study finds brain stores motor memories differently based on decision uncertainty
A study published in the journal Nature Human Behaviour challenges the belief that identical physical actions are governed by the same motor memory, regardless of the decision-making process involved. Researchers from the National Institute of Information and Communications Technology (NICT) and HONDA R&D Co., Ltd. have discovered that the brain differentiates and stores motor memories based on the level of uncertainty experienced during decision-making.
In a football (soccer) penalty shootout, a player may decide to confidently kick the ball to the right corner upon observing the goalkeeper moving in the opposite direction. Alternatively, the player might make the same kick while being unsure about the goalkeeper’s movement.
Although the physical action—kicking the ball to the right—is identical in both scenarios, this new study reveals that the brain tags these actions differently based on the decision uncertainty involved. This discovery suggests that motor memories are not simply repetitions of the same action but are influenced by the cognitive processes leading up to them.
Stanford Engineers a Pocket-Sized Titanium-Sapphire Super Laser
In a single leap from tabletop to the microscale, engineers at Stanford University have produced the world’s first practical titanium-sapphire laser on a chip.
Researchers have developed a chip-scale Titanium-sapphire laser that is significantly smaller and less expensive than traditional models, making it accessible for broader applications in quantum optics, neuroscience, and other fields. This new technology is expected to enable labs to have hundreds of these powerful lasers on a single chip, fueled by a simple green laser pointer.
As lasers go, those made of Titanium-sapphire (Ti: sapphire) are considered to have “unmatched” performance. They are indispensable in many fields, including cutting-edge quantum optics, spectroscopy, and neuroscience. But that performance comes at a steep price. Ti: sapphire lasers are big, on the order of cubic feet in volume. They are expensive, costing hundreds of thousands of dollars each. And they require other high-powered lasers, themselves costing $30,000 each, to supply them with enough energy to function.
Scientists Uncover Brain-Boosting Potential of Vitamin B6
Researchers found that inhibiting the degradation of vitamin B6 in cells using 7,8-Dihydroxyflavone enhances brain functions and could offer a new treatment method for mental and neurodegenerative disorders.
Vitamin B6 plays a crucial role in brain metabolism. Consequently, low levels of vitamin B6 are linked to memory and learning impairments, depressive moods, and clinical depression in various mental disorders. In the elderly, insufficient vitamin B6 is associated with memory decline and dementia.
Although some of these observations were made decades ago, the exact role of vitamin B6 in mental illness is still largely unclear. What is clear, however, is that an increased intake of vitamin B6 alone, for example in the form of dietary supplements, is insufficient to prevent or treat disorders of brain function.
Parkinson’s Link to Gut Bacteria Suggests Unexpected, Simple Treatment
Researchers have suspected for some time that the link between our gut and brain plays a role in the development of Parkinson’s disease.
A new study just identified gut microbes likely to be involved and linked them with decreased riboflavin (vitamin B2) and biotin (vitamin B7), pointing the way to an unexpectedly simple treatment that may help: B vitamins.
“Supplementation of riboflavin and/or biotin is likely to be beneficial in a subset of Parkinson’s disease patients, in which gut dysbiosis plays pivotal roles,” Nagoya University medical researcher Hiroshi Nishiwaki and colleagues write in their published paper.
Activating molecular target reverses multiple hallmarks of aging
MD Anderson researchers identify molecule that reduces age-related inflammation and improves brain and muscle function in preclinical models.
MD Anderson News Release June 21, 2024
Researchers at The University of Texas MD Anderson Cancer Center have demonstrated that therapeutically restoring…
The study, published today in Cell, identified a small molecule compound that restores physiological levels of telomerase reverse transcriptase (TERT), which normally is repressed with the onset of aging. Maintenance of TERT levels in aged lab models reduced cellular senescence and tissue inflammation, spurred new neuron formation with improved memory, and enhanced neuromuscular function, which increased strength and coordination.
The researchers show that TERT functions not only to extend telomeres, but also acts as a transcription factor to affect the expression of many genes directing neurogenesis, learning and memory, cellular senescence, and inflammation.