Neuroscientist and McGill University psychology professor Karim Nader guided the audience through the mechanisms behind Eternal Sunshine of the Spotless Mind in his talk about memory modification.

In the late ’90s, Nader hypothesized that memories were unstable and could be modified. His hypothesis was confirmed after laboratory experience, and his work reignited previously tested but forgotten proposals.

Nader went on to show clips from the film, in which the characters undergo the clinical process of “memory modification” in order to forget painful memories associated with their romantic relationships. When he asked if the audience would do the same—“If you could erase certain memories, would you?”—no one raised their hand.

The lack of enthusiasm didn’t surprise Nader, who acknowledged that memories shape our identity, and instead proposed a new type of memory reconsolidation. Instead of completely erasing the memory, he “rewires” it, a process that eliminates only the emotional stress associated with a traumatizing memory.

He tested this method on patients with post-traumatic stress disorder (PTSD) in 2008 by giving them propranolol, a drug that inhibits the neurotransmitters associated with fear. By having patients recount the traumatic event as vividly as possible, they effectively reignited the strong emotions causing their disorder. The drug was then able to “rewire” the brain’s response to the memory and block the protein synthesis creating the emotional response.

For one patient who had been raped as a child by her doctor and could not comfortably undress in front of her husband, Nader’s rewiring treatment led her to feel no symptoms of PTSD associated with the rape.

Nader was twice published in the science journal Nature and was named one of Cadwell Partners International’s Top 40 Under 40 in 2006.