This New York Times story describes research that may, in the future, lead to technologies that may help people with memory problems, such as those who have had a traumatic brain injury. Although the technique of brain stimulation has been used before to try to enhance memory function, sometimes it has been found to help and other times to hinder remembering. The current study shows that timing of the stimulation is possibly important, and tends to help memory when “people are in a low or foggy state,” while hindering it otherwise.
The story’s headline misrepresents the findings–at this point, we’re far from knowing if this “pacemaker for the brain” can indeed help memory among people with traumatic brain injury, dementia or other diseases. It also needed more on the cost of brain implant surgery, and the risks associated with the devices and their installation.
This research is a step forward in the field, but it’s a long way from what doctors call “clinical applicability”–meaning that it has been proven safe and effective.
The story could have noted how much it typically costs to implant electrodes in the brain of a patient. According to the University of Michigan, deep brain stimulation implants and surgery can cost “about $30,000 plus physician and MRI fees.” Meanwhile, the National Parkinson Foundation states the all-in cost can reach $50,000 and sometimes up to $100,000 (e.g. for implants on both sides of the brain).
Readers get two sets of numbers on the effect size: Patients who were gently zapped when their brains were learning words during a foggy, “low-functioning state” could remember words 12%-13% better. Stimulation during a clear-minded, “high-functioning state,” however, resulted in 15%-20% worse performance.
What’s missing, however, is a definition and context for these numbers. We had a lot of questions: Do they reflect the number of words recalled? How correct (or incorrect) their order during recall was? Or that people remembered them more or for less time compared to no stimulation? Or some other measure? Were these statistically significant results? Also, how did the researchers determine if a person was experiencing a “high-functioning” or “low-functioning” state?
The story explains that brain stimulation can weaken memory formation, and notes how brain implants require “a delicate procedure” to pull off. However, the risks of brain implant devices aren’t discussed — and they’re significant. According to Johns Hopkins University, surgery to implant electrodes in the brain carries a number of risks, including bleeding in the brain, leaking of spinal fluid into the brain, infection stroke, and more. After surgery, brain implants can cause tingling in the face and limbs, problems with speech or vision, dizziness, and other side effects.
We liked that readers are cautioned that the “reported improvements may not apply broadly” and that the work examined only epilepsy patients — suggesting the technique may not work for people with other conditions, or people in general.
One area of concern that we wish the story had flagged: Readers are told that data from 150 people were used in the study, but it appears the study used data from only 102 of those people, and then only a subset of these people had the stimulation, making it a pretty small sample size to measure effect.
We didn’t detect any disease-mongering in this story.
The end of the scientific article that this story was based on notes that the two senior authors are forming a company “to develop and commercialize brain stimulation therapies for memory restoration.” This should have been included in the story.
Since there are really no alternatives as far as treatment goes, we’ll rate this N/A.
It’s made clear that this study focused on epilepsy patients whose doctors deemed they needed brain-stimulating implants, and that the research may not apply to broader populations.
The story sums up decades of conflicting work on stimulating the brain to improve memory, and how changing the timing of stimulation — specifically, during times when memory encoding may be poor — seems to represent a significant advancement in the field.
No quotes or even framing seem to have been copied from a news release posted by the University of Pennsylvania.