Brain stimulation boosts memory replay, accuracy

You might remember you ate cereal for breakfast but forget the color of the bowl. Or recall watching your partner put the milk away but can’t remember on which shelf.

A new Northwestern Medicine study improved memory of complex, realistic events similar to these by applying transcranial magnetic stimulation (TMS) to the brain network responsible for memory. The authors then had participants watch videos of realistic activities to measure how memory works during everyday tasks.

The study found that brain stimulation led to higher quality reinstatement of memories in the brain. Reinstatement is when the brain replays or relives an original event, said lead author Melissa Hebscher, a postdoctoral fellow at Northwestern University Feinberg School of Medicine.

Following stimulation, a person’s brain activity while remembering a video more closely resembled their brain activity when they watched that same video for the first time.

“This is why remembering can sometimes feel like ‘mental time travel,’” Hebscher said. “Our findings show that stimulation enhances memory replay in the brain and improves accuracy. These findings have implications for the development of safe and effective ways to improve real-world memory.”

The study was conducted on healthy young adults in a controlled laboratory setting. These methods, however, also could eventually be used to improve memory in individuals with memory disorders due to brain damage or neurological disorders, Hebscher said.

The study was published Feb. 4 in the journal Current Biology.