Henry Krasner, Claire Victoria Ong, Paige Hewitt, and Thomas A. Vida (Medicine) published a critical review in the International Journal of Molecular Sciences that sheds new light on what’s driving this mental health crisis: chronic stress may not just change how we feel—it may physically change how our brains work. 

Mood disorders — like depression and anxiety — affect hundreds of millions of people worldwide and are now among the leading causes of disability and lost productivity.

According to the study, prolonged stress can shrink and damage neurons in brain regions that regulate emotion, memory, and decision-making. This process, called neuronal atrophy, contributes to the emotional instability, fatigue, and cognitive fog that many people with depression and anxiety experience. As many as 30% of patients with depression don’t respond to standard treatments like antidepressants—suggesting that chemical imbalances alone don't tell the whole story.

But there’s hope. The work spotlights emerging therapies — such as ketamine, psychedelics, and anti-inflammatory agents — that may not only relieve symptoms but help the brain heal. By focusing on how stress impacts brain structure, this UNLV-led work could pave the way for more effective, longer-lasting treatments for mood disorders—conditions that now account for over 14% of global deaths linked to mental illness.