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Stress Social Deficits Reversed by Amygdala-Oxytocin Circuit Suppression

MHD featured image for stress-induced social changes, mPFC, amygdala, and oxytocin circuits.

A 2026 mouse circuit study found that restraint stress progressively reduced medial prefrontal social coding: mPFC excitatory-neuron transient rates fell to roughly 70-80% of baseline after acute stress and nearly 50% after chronic stress, while suppressing either basolateral-amygdala input or hypothalamic oxytocin input restored social discrimination and behavior.1 The result is a circuit-specific oxytocin finding, …

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DNA Methylation Biological Age Slope Raised Mortality Risk 28%

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A 2026 Clinical Epigenetics study tracked DNA methylation biological age in 894 older adults and found that each 1-SD higher biological-age slope predicted 17-28% higher all-cause mortality risk across 5 epigenetic clocks.1 The clocks moved more slowly than calendar time over 8.1 years, but participants with higher methylation-age slopes had worse survival than participants with …

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qMRI Brain Aging Maps Myelin, Iron, and Water in 138 Adults

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A 2026 quantitative MRI preprint reanalyzed 138 healthy adults and found that multivariate modeling detected coordinated age-related shifts across myelin-sensitive, iron-sensitive, and water-sensitive brain maps.1 The signal was broad, but split-half validation weakened the result enough to keep it in the measurement-method lane rather than the clinical-test lane. Research Highlights 138 adults were reanalyzed: The …

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PINK1 and Parkin Link Parkinson’s Disease to Failed Mitochondrial Cleanup

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A 2026 review ties the Parkinson’s disease genes PINK1 and parkin to damaged-mitochondria cleanup, from damage sensing and ubiquitin tagging to autophagy recruitment and lysosomal degradation.1 That shifts “mitochondrial dysfunction” into specific failure points: tagging, extraction, transport, autophagosome recruitment, and degradation. Research Highlights 18 PARK loci frame inherited risk: PARK2 encodes parkin and PARK6 encodes …

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Stress Suppressed Food-Cue Reward Through NTS A2 Dopamine Circuits

MHD featured image for stress, food cues, NTS A2 neurons, and dopamine reward circuitry.

A 2026 rat study found that foot-shock stress transiently reduced food-cue approach during the first 2 conditioned-stimulus trials (t = 2.807; P < 0.05), and inhibiting the nucleus of the solitary tract weakened that stress effect.1 The useful finding is selective: stress used an NTS-linked route to dampen cue-evoked VTA dopamine, while outcome-specific satiety reduced ...

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