A newly identified brain circuit may hold the key to understanding why some pain fades while other pain lingers long after injury.
Category: neuroscience – Page 23
Tomatidine is a senotherapeutic compound that improves cognitive function and reduces cellular senescence in aged mice
Cellular senescence drives aging and age-related dysfunction across multiple tissues, including the brain. Through a high-content, senescent cell-based phenotypic screen of a small panel of natural products, we identified tomatidine, an aglycone of tomatine found in tomatoes, as a previously unrecognized senotherapeutic agent. In senescent human brain microvascular endothelial cells and fibroblasts, tomatidine selectively suppressed SASP expression without affecting p16Ink4a or p21Cip1 levels consistent with a senomorphic effect. In aged mice, tomatidine reduced frailty and improved motor coordination and cognitive performance. These functional benefits were accompanied by reduced senescence markers (p16 Ink4a, p21 Cip1, and telomere-associated DNA damage foci) in liver, skin, and hippocampal neurons, along with decreased neuroinflammation and microglial activation. Tomatidine also diminished brain endothelial cell senescence while enhancing tight junction protein expression, suggesting preserved blood–brain barrier integrity. Together, these findings identify tomatidine as a promising senescence-targeting compound with beneficial effects in aged mice and support its further evaluation in mechanistic and translational studies.
New ‘Unifying Theory’ May Explain How Alzheimer’s Emerges in The Brain
The origins of Alzheimer’s remain contentious, but a new study suggests the disease may emerge as two key proteins compete inside brain cells.
Alzheimer’s disease, the most common form of dementia, has long been associated with the build-up of two proteins in the brain: amyloid-beta and tau.
This new study ties those two together, offering a “unifying theory” that, according to the team of chemists proposing it, resolves some conflicting ideas about Alzheimer’s.
How the human brain builds our sense of time
How does Jannik Sinner manage to hit the ball at exactly the right moment, with remarkable precision? And how do we, in everyday life, perceive the duration of events around us? The answer lies in how the brain constructs the perception of time, as shown by research published in PLOS Biology by Valeria Centanino, Gianfranco Fortunato, and Domenica Bueti. Starting from what we see—such as an approaching ball—temporal information is processed by the brain through progressively more complex stages: from the occipital visual cortex, to parietal and premotor areas, and finally to frontal regions.
Using high-field functional magnetic resonance imaging (fMRI) and measuring time perception in healthy volunteers, the researchers shed light on what happens in the brain when we estimate the duration of a visual stimulus. “Our results show that time perception is not a unitary process, but the outcome of multiple processing stages distributed across the cerebral cortex,” the authors explain. “Each stage contributes differently, from encoding physical duration to constructing the subjective experience of time.”
In an initial stage, occipital visual areas encode duration through gradual (monotonic) neural responses: the longer the stimulus, the stronger the neural response. This information is then transformed in parietal and premotor regions into selective (unimodal) representations, where distinct neural populations respond preferentially to specific durations, enabling the “readout” of time. Finally, higher-order regions, including the frontal cortex and anterior insula, are involved in the subjective categorization of duration, shaping how time is perceived.
Abstract: Genetic analysis of neurodegenerative diseases:
As part of the JCI’s Review Series on Neurodegeneration, Sonja W. Scholz and colleagues highlight key genomic technologies advancing diagnosis and research in neurodegeneration.
1Neurodegenerative Diseases Research Section, National Institute of Neurological Disorders and Stroke;
2Neurogenetics Branch, National Institute of Neurological Disorders and Stroke; and.
3Neuromuscular Diseases Research Section, National Institute on Aging, National Institutes of Health (NIH), Bethesda, Maryland, USA.
How beliefs about demons shape the experience of mental illness
For some evangelical Christians, attributing mental illness to demonic forces can offer a sense of meaning, while for others, it creates harmful barriers to medical care. A recent qualitative study published in Spirituality in Clinical Practice outlines how these widespread spiritual explanations act as a double-edged sword for individuals experiencing psychological distress. The research indicates that integrating religious beliefs with standard psychiatric care may be a safer path forward for many faith communities.
Religion frequently shapes how people interpret their physical and mental health. Psychologists recognize that religious frameworks offer a primary system for individuals to make sense of the world around them. By relying on theological teachings, people construct meaning around their personal suffering. This process of religious meaning construction can influence health outcomes in both positive and negative directions.
Within evangelical Christianity, foundational teachings often emphasize the active existence of spiritual forces. This includes the belief that angels, demons, and other supernatural entities directly influence the physical world. This worldview can lead to the belief that spiritual forces cause human ailments, including severe psychological distress.
Demon face syndrome: The science behind prosopometamorphopsia
Imagine looking at a loved one and seeing their face twist into a demonic, unnatural shape. Their eyes might stretch to the sides of their head, their nose might swell, and deep, unnatural grooves might appear across their cheeks and forehead. This terrifying visual experience belongs to a rare neurological condition known medically as
In popular media and online discussions, it is sometimes referred to as “demon face syndrome.” People with this condition see human faces as severely distorted, even though their vision for everyday objects remains completely normal.
Prosopometamorphopsia is fundamentally different from a hallucination. A hallucination involves seeing something that is not actually present in the physical world. People experiencing these facial distortions are looking at a real person standing in front of them. Their brain simply alters the shape, size, color, or position of the facial features before the image reaches their conscious awareness.