Three recent studies from psychology and neuroscience research:
What Happens in the Brain When Cannabis Triggers Anxiety
Northwestern University researchers gave mice a synthetic cannabinoid drug, then exposed them to a threatening predator odor (fox urine). The drugged mice froze more and spent less time investigating the odor. The anxious behaviors were linked to the drug weakening the brain's natural "brake" on a small group of somatostatin neurons in the central amygdala (a fear/stress region); genetically silencing those neurons reduced the avoidance. Senior author: Dr. Sachin Patel. Published in Nature Communications (October 2026). This was an animal study, so the findings do not directly transfer to people.
Source: Medical Xpress
Brain Scans Show Shared and Drug-Specific Changes During Early Depression Treatment
Stanford University School of Medicine and University of Texas at Austin researchers analyzed resting-state fMRI scans from 386 adults with major depressive disorder, before and one to two weeks after starting a placebo (125 people), sertraline (123), or escitalopram (138). Connectivity increased in a visual-precuneus-thalamus system across all groups regardless of symptom improvement, while placebo-linked improvement involved the striatum and attention networks. Antidepressant-specific changes in the amygdala, midcingulate, orbitofrontal cortex, and cerebellum appeared only in a subset of medicated patients. Published in Nature Mental Health (2026). The authors say the early-scan patterns could eventually inform treatment selection, but more research is needed first.
Source: Medical Xpress
A Specific Brain Circuit Implicated in OCD
Stony Brook University researchers, led by Joshua L. Plotkin, identified a previously unknown direct connection from the basolateral amygdala to the dorsolateral striatum in a mouse model of OCD. Stimulating this small circuit amplified sensory-evoked grooming behaviors even after stimulation stopped, and chronically inhibiting the amygdala prevented OCD-like behavior in the mouse model. The mouse model responds to the same medications used to treat human OCD, but this is animal research and any treatment targets remain to be tested. Published in Neuron (2026).
Source: Medical Xpress