A 36-person experiment found that 18 Hz infrasound raised salivary cortisol and negative mood appraisal even though participants did not detect the infrasound above chance (p = 0.241).1 The result is a controlled acute signal, not proof that every real-world low-frequency noise complaint is physiologically caused by infrasound. Research Highlights Cortisol rose with infrasound: Infrasound …
A 40-rat early-life visceral stress study found auditory pathway sensitization without hearing-threshold loss: neonatal colorectal distension produced IBS-like visceral hypersensitivity, normal ABR thresholds, shortened auditory brainstem latencies, increased amplitudes, and 219 differentially expressed cochlear proteins.1 The result turns IBS-like stress exposure into a gut-pain and sensory-processing question. Research Highlights Visceral hypersensitivity was strong: At 20 …
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 …
Cannabis users often say the drug helps them blunt stressful memories. A 2026 randomized trial of 36 healthy adults tested low-dose oral THC against placebo during retrieval of a standardized lab stressor, and on every subjective and physiological measure that mattered, THC did nothing.1 Research Highlights 36-adult, 3-arm RCT: participants got placebo, 5 mg oral …
A Wuhan cohort of 2,210 pregnant women found that mid-pregnancy sleep disturbance was common enough to screen for and associated with several birth-outcome signals. Depressive symptoms, pre-pregnancy alcohol use, and moderate-to-severe vomiting raised sleep-disturbance odds, while higher dietary variety was protective.1 Research Highlights 18.14% had sleep disturbance: Pittsburgh Sleep Quality Index (PSQI) scores greater than …
A 7-day mind-body retreat study in 20 healthy adults found pre/post shifts across fMRI brain networks and plasma biology, with p values as low as 0.000003.1 Those numbers are striking, but the design was observational, so the honest reading is biological signal without causal isolation. Research Highlights Neural signal was broad: Meditation-state fMRI showed lower …
A 2026 randomized exploratory pilot found that a single 24-minute yoga session did not significantly lower salivary cortisol or salivary alpha-amylase compared with quiet sitting in 19 stressed adults.1 The acute yoga signal was physiological but not the simple stress-biomarker drop that wellness claims often imply. Research Highlights Biomarker claim failed: Yoga did not significantly …