Are hormones the key to slowing the aging process?
Category: neuroscience – Page 24
Rare genetic variants can increase ADHD risk by up to 15 times
ADHD is a neurodevelopmental disorder with a high heritability, in which the genetic component consists of thousands of genetic variants. Most variants only slightly increase the likelihood of receiving the diagnosis. Now an international study led by researchers from iPSYCH at Aarhus University has shown that rare high-effect genetic variants also play an important role.
The study has been published in Nature, and the researchers have found a markedly increased likelihood of developing ADHD among individuals carrying rare variants in three genes—MAP1A, ANO8 and ANK2—in some cases by up to 15 times.
These genetic variants are very rare, but when present, the study shows that they strongly affect genes expressed in the brain’s nerve cells. In individuals carrying these variants, the development and communication between nerve cells may therefore be disrupted, which can result in ADHD.
DNA polymerase β suppresses somatic indels at CpG dinucleotides in developing cortical neurons
New research finds that dying cells leave a “footprint of death” that guides immune responses — but viruses like influenza can exploit this signaling. The discovery, published in Nature Communications, offers new insight into cell death, viral transmission, and potential drug targets.
New insights into the aftermath of cell death might ultimately inform drug development.
Qualia as Structured Silence: Colour Opponency via Dual-Regime Refusal
By: Alastair Waterman https://www.facebook.com/share/p/1N1TBvEKuF/
Why does red feel exactly like red, green exactly like green, and why can these two experiences never, ever swap places?
Most current theories of consciousness have no real answer. They explain how the brain detects wavelength, but not why one neural pattern feels “red” and its literal opponent feels “green”
Refusal-Driven Dimensionality Reduction Theory (RDRT) offers the first direct mechanism.
Colour vision is opponent at every level: red and green are mutually exclusive from retina → LGN → V1 → V4 → inferotemporal cortex.
This hard-wired mutual exclusion is a multi-level structural refusal.
The claim: The specific feeling of redness is not the spikes that are transmitted.
It is the precise, reproducible shape of what is refused transmission — a stable ~55–65-event “hole” carved into each gamma cycle in the anterior cingulate cortex and self-monitoring networks.
Scientists Call Age-25 Cannabis Rules a Myth
“This Perspective concludes that an MLA between 18–21 years is a scientifically supportable and socially coherent threshold for non-medical cannabis use.”
What should be the minimum legal age for recreational cannabis? This is what a recent study published in The American Journal on Drug and Alcohol Abuse hopes to address as a team of scientists investigated the benefits and challenges of raising the legal age for using recreational marijuana to 25, with the current age range being 18 to 21, depending on the country. This study has the potential to help researchers, legislators, and the public better understand the neuroscience behind the appropriate age for cannabis use.
For the study, the researchers examined brain development for individuals aged 18–25, specifically regarding brain maturation and whether this ceases before age 25. They note it depends on a myriad of factors, including sex, geographic region, and physiology. This study comes as Germany recently published several studies regarding legalizing recreational marijuana nationwide and marijuana use rates post-legalization. In the end, the researchers for this most recent study concluded that raising the minimum legal age for recreational cannabis use to 25 is unnecessary.
The study notes, “This Perspective concludes that an MLA between 18–21 years is a scientifically supportable and socially coherent threshold for non-medical cannabis use. Policy decisions should be informed not only by neurobiological evidence but also by legal, justice, sociocultural, psychological, and historical considerations.”