Neuroscientist Explores Potential of Memory Manipulation

Steve Ramirez discusses how memories can be activated, edited, and even implanted in the brain

Published on Feb. 26, 2026

Got story updates? Submit your updates here. ›

Neuroscientist Steve Ramirez discusses his research into memory manipulation, including his breakthrough in 2012 where he and his lab partner Xu Liu were able to artificially activate a memory in the brains of mice using lasers. Ramirez explains how memories are formed and recalled in the brain, and the potential applications of being able to edit or even implant memories, particularly for treating disorders like PTSD and addiction. However, he also acknowledges the ethical concerns around memory manipulation and the need for responsible use of this technology.

Why it matters

Memory is core to the human experience, so the ability to manipulate memories has significant implications, both positive and negative. While memory manipulation could help treat certain disorders, there are also concerns about the potential for misuse, such as the CIA's past experiments with mind control. Responsible development and use of this technology is crucial.

The details

Ramirez and his lab partner Xu Liu were able to use optogenetics, or light-sensitive switches, to activate a specific memory in the brains of mice. They could turn the memory on by shining a laser on the brain cells associated with that memory, and turn it off by turning the light off. This breakthrough allowed them to study how memories are formed and recalled in the brain. Ramirez believes this technology could be used to help treat disorders like PTSD and addiction by selectively editing or dampening negative memories, while preserving the overall memory. However, he acknowledges the ethical concerns around memory manipulation and the need to prevent misuse.

  • In 2012, Ramirez and Xu Liu conducted their breakthrough experiment activating a memory in mouse brains.
  • In 2013, Ramirez and Liu gave a TED talk about their research.
  • Xu Liu passed away suddenly in 2015.

The players

Steve Ramirez

An associate professor of psychological and brain sciences at Boston University and author of the book "How to Change a Memory: One Neuroscientist's Quest to Alter the Past."

Xu Liu

Ramirez's lab partner who helped develop the tools to visualize and activate memories in the mouse brain.

Waymo

An American autonomous driving company and a subsidiary of Alphabet Inc., Google's parent company.

Got photos? Submit your photos here. ›

What they’re saying

“We hope to convince you that now, we're actually able to activate a memory in the brain at the speed of light. To do this, there's only two simple steps to follow. First you find and label a memory in the brain, and then you activate it with a switch. As simple as that.”

— Xu Liu (TED Talk)

“Finding a memory in the brain isn't all that easy. This is way more difficult than, let's say, finding a needle in a haystack. Because at least, you know, the needle is still something you can physically put your fingers on. But memory is not.”

— Xu Liu (TED Talk)

The takeaway

Memory manipulation is a powerful but ethically complex technology. While it has potential applications in treating certain disorders, there are valid concerns about the potential for misuse. Responsible development and use of this technology, with robust safeguards and public oversight, will be crucial as the science advances.