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Catatonia Brain Circuits: Limbic System Review

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A 2026 systematic review argues that catatonia should be read as a limbic-cortical circuit syndrome, with motor shutdown tied to brain systems for threat, salience, motivation, and emotional regulation. Research Highlights 20 studies met criteria: the 2026 review screened 1,792 records, assessed 54 full texts, and included 20 articles: 13 observational studies and 7 case …

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Rats Beat Humans in 2-Second Temporal Error Monitoring Study

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A 2026 iScience study found that both humans and rats could report whether their own 2-second timing responses were small-error or large-error trials, but rats were more accurate on test choices: human accuracy was 55%-57%, rat accuracy was 65%-67%, and the species gap remained significant before task-variable matching.1 Research Highlights Both species monitored timing errors: …

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Dream Content Tracks Personality, Sleep Quality, and Stress

Dreams transform waking life rather than replaying it directly. In a 2026 Communications Psychology study of 3,366 reports, dreams were more visual, spatial, social, and bizarre than waking reports, while attitude toward dreaming, mind-wandering tendency, sleep quality, and COVID lockdown stress each left measurable fingerprints on dream content.1 Research Highlights Dreams were not random word …

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Oxidative Stress Reduced Brain DUB Activity by Nearly 40% With Age

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A Nature Communications study found that old vertebrate brains lost almost 40% of cysteine protease deubiquitylase catalytic activity with age, despite relatively stable protein abundance.1 Antioxidant treatment with NACET restored DUB activity in aging brains, making the finding a reversible enzyme-mechanism result rather than a generic “antioxidants reverse brain aging” claim. Research Highlights DUB activity …

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Restless Legs: Striatal Dopamine-Opioid Hypersensitivity

Restless legs syndrome (RLS) and opioid-withdrawal restlessness both produce night-worsening urges to move. A 2026 npj Parkinson’s Disease mouse study tied that overlap to hypersensitive striatal D1-mu-opioid receptor signaling in basal-ganglia motor circuits.1 Research Highlights 2 clinically similar states converged: restless legs syndrome and opioid-withdrawal restlessness both point toward a striatal D1-mu-opioid circuit that regulates …

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PTSD Counterconditioning Strengthened fMRI Safety Memory

A 2026 functional magnetic resonance imaging study involving 54 adults found that pairing a formerly threatening cue with positive images, a laboratory method called counterconditioning, strengthened later neural safety-memory signals in people with posttraumatic stress disorder. The experiment measured fear-learning biology, not PTSD symptom improvement after therapy.1 Research Highlights 54 adults were analyzed: Cooper et …

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tDCS Plus Cognitive Training Improved Cognition Short-Term by SMD 0.36

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A 2026 medRxiv meta-analysis of 27 trials found that transcranial direct current stimulation added to cognitive training improved global cognition immediately after treatment by SMD 0.36 compared with cognitive training alone.1 The signal was small, short-term, and rated very low certainty, so it is not evidence that tDCS is a durable cognitive-rehabilitation shortcut. Research Highlights …

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