Stress reduction correlates with structural changes in the amygdala.
Level 4 - case-series / case-control
Uncontrolled longitudinal pre-post cohort study
PubMed 19776221 · doi:10.1093/scan/nsp034
What was done
Twenty-six stressed but otherwise healthy individuals completed an 8-week mindfulness-based stress reduction (MBSR) intervention. Participants completed the Perceived Stress Scale (PSS) and underwent anatomical MRI pre- and post-intervention. Changes in PSS scores were used as a predictive regressor for changes in bilateral amygdala gray matter density.
What was found
Participants reported significantly reduced perceived stress post-intervention. Decreases in perceived stress correlated positively with decreases in right basolateral amygdala gray matter density. The abstract does not report specific numerical values, correlation coefficients, or p-values.
Why it matters
It provides preliminary longitudinal evidence that self-reported psychological stress reduction from a behavioral program is associated with structural neuroplastic changes in the human amygdala.
Limits
The study is limited by a small sample size (n = 26) and the lack of an active or passive control group, meaning changes cannot be definitively attributed to the mindfulness intervention versus time or non-specific effects. No exact statistics or effect sizes are provided in the abstract.
Cited by
- supports An eight-week meditation training program in meditation-naive individuals caused structural and functional changes in brain regions, including decreased amygdala size and activity and increased prefrontal cortex activity.