Summary: Researchers have identified a mutation in the TREM2 gene that interferes with the brain’s ability to clear toxic amyloid plaques and raises risk for Alzheimer’s disease. The mutation, called T96K, is a gain-of-function change that leaves TREM2 chronically overactive. Paradoxically, this overactivity undermines microglial plaque-clearing activity, with especially noticeable effects in female mice in … Read more

Summary: A new study finds that older adults are more likely than younger people to interpret ambiguous facial expressions as happy rather than angry. High-resolution brain imaging links this positivity bias to increased activity in the locus coeruleus — a small brainstem nucleus that helps regulate alertness and stress — and to stronger coupling between … Read more

Summary: An international research team has mapped, on a millisecond time scale, the precise sequence by which nerve signals trigger muscle activation. Their work reveals a previously unseen intermediate “primed” state in the activation pathway of neuromuscular receptors and shows that the receptor subunits move asynchronously rather than in a single coordinated motion. This finding … Read more

Summary: New research shows that childhood maltreatment leaves measurable biological “scars” on DNA and is associated with lasting changes in brain structure and function. A genome-wide epigenetic analysis identified four DNA methylation sites—ATE1, SERPINB9P1, CHST11, and FOXP1—that consistently relate to maltreatment exposure. Alterations in FOXP1 were particularly notable: higher methylation at this site correlated with … Read more

Summary: A new study shows that although individual human brains are wired differently, they can represent the world in remarkably similar ways. Researchers recorded live neuronal activity from patients with epilepsy and found that while the exact neurons that respond to an image vary between people, the relationships among those responses—the pattern of similarities and … Read more

Summary: New research from RIKEN shows that astrocytes — not neurons alone — play a central role in stabilizing emotionally charged memories. After a stressful event such as fear conditioning, small groups of astrocytes become biologically marked by upregulating adrenoreceptors, making them responsive when the memory is later reactivated. Interrupting these astrocytes during recall weakens … Read more

Summary: A new study from the Picower Institute at MIT reveals how newly formed synapses gradually mature to transmit chemical signals correctly. Using time-stamped fluorescent markers in fruit flies, researchers tracked the sequential assembly of proteins at presynaptic active zones and showed that full functional maturation takes days and requires neural activity. When neural activity … Read more

Summary: A UCL study found that women’s cognitive performance—measured by reaction time and accuracy—peaked at ovulation, but physical activity level had a far greater overall impact. Inactive participants were, on average, about 70 milliseconds slower and made roughly three times more impulsive errors than active women, independent of menstrual phase. The research indicates that regular … Read more

Summary: New research shows that our bodily movements can change how we interpret facial expressions. In virtual reality experiments, participants were more likely to judge a face as angry when they actively moved away from it than when the face moved away from them. The findings reveal a bidirectional link between movement and emotion recognition: … Read more

Summary: Researchers at Texas A&M report that two forms of estrogen—estradiol and estriol—can reduce spinal cord inflammation and protect nerve fibers in a virus-based model of progressive multiple sclerosis (MS). Both hormones lowered inflammation, while estradiol provided stronger preservation of the myelin sheath that insulates axons. These results mirror the symptom relief many women with … Read more