Non-Invasive Stimulation Of The Eye Could Potentially Treat Depression And Dementia

Mental health has always been a sensitive subject, and dealing with mental health is often viewed as something negative, a weakness, as some would say.

But depression is considered one of the most common mental disorders around the world. Nowadays, as more people become open and vocal with both their struggles and their victories in conquering their mental health issues, the negative stigma around it is slowly getting erased.

Unfortunately, the recent pandemic brought about a massive increase in people showing signs of anxiety and depression, and experts say that around a quarter of patients don’t respond well to current treatments available in the market.

An amazing new study was just recently published where researchers discovered a new possible treatment for depression and dementia using a non-invasive procedure on the eye.

A research team discovered that electrical stimulation on the surface of the eyes can somehow alleviate depression-like symptoms and improve cognitive function in animal models.

Back in 2015, researchers reported that stimulation of the prefrontal cortex in animal brains could improve memory function and relieve depression-like symptoms as well. But the 2015 study used invasive deep-brain stimulation, a procedure that requires surgery to implant electrodes in the brain. With side effects including infection and post-operative complications, this invasive surgery can be dangerous.

Now a new team of researchers, led by Lee Wei Lim, also a researcher from the 2015 study, has been looking for other ways to treat neuropsychiatric diseases. Unlike the invasive surgery from before, this team discovered a non-invasive way to create a similar therapeutic effect on the brain.

Stimulation of the corneal surface of the eye, which activates brain pathways, resulted in therapeutic, antidepressant effects and reduced stress hormones in an animal model. And while invasive brain surgery comes with a lot of other cons, this non-invasive technique comes with a pro. The eye stimulation technique induced the expression of genes involved in the development and growth of brain cells in the hippocampus.

A separate study was also conducted to test if this non-invasive procedure could be used for other diseases, dementia in particular. Researchers used mice models to test the technique to treat Alzheimer’s disease, and they found out that it improved memory performance and reduced beta-amyloid deposits in the hippocampus, which is one of the hallmarks of Alzheimer’s disease.

“Transcorneal electrical stimulation is a non-invasive method initially developed to treat eye diseases, and it would be a major scientific breakthrough if it could be applied to treat neuropsychiatric diseases,” said Leanne Lai Hang Chan, an expert on the electrical stimulation of visual and non-visual brain targets and co-author of the study.

Another co-author, Ying-Shing Chan, added that “these research findings pave the way for new therapeutic opportunities to develop novel treatments for patients suffering from treatment-resistant depression and dementia. Nevertheless, clinical trials must be conducted to validate the efficacy and safety.”

Check out how they do Transcorneal Electric Stimulation (TES) in the video below.