Wallis Lab

1. Neural implants to unlearn maladaptive associations

Lead Investigators: Erin Rich, Eric Knudsen, Nina Lopatina

Potential treatments: Addiction, PTSD, depression

Current methods for treating neuropsychiatric conditions rely on relatively crude brain manipulations. Pharmaceutical treatments modulate neurotransmitter systems, but those systems serve multiple functions, all of which will be affected by a pharmaceutical intervention. The treatment typically involves a blancing act between inefficacy and severe side effects. Deep brain stimulation (DBS) involves disrupting the function of a brain area indefinitely. Such crude interventions have had success for only limited patient groups and they raise the question as to whether they are likely to have had broad success across the spectrum of neuropsychiatric disorders. For example, consider treating an addict. Our current theoretical understanding of the neural underpinnings of addiction is that it arises because a specific reward has become excessively valuable compared to other rewards. Our current methods of intervention do not allow us to target this reward without also affecting other rewards, including natural rewards and social and emotional rewards. Therefore it is questionable whether pharmaceutical manipulations or DBS will be effective in treating addiction.


Many neuropsychiatric disorders involve relatively specific neural representations. For example, drug-seeking behavior in addicts is often precipitated by intense craving elicited by a specific cue, such as an advert for beer in an alcoholic. Similarly, post-traumatic stress disorder (PTSD) can be elicited by cues associated with the traumatic event while obsessive-compulsive disorder (OCD) is often precipitated by a relatively restricted set of thoughts or environmental stimuli (e.g. perception of germs in OCD hand-washing). These ‘triggers’ are often the focus of psychological treatments, such as cognitive-behavioral therapy, but neuroscience has, to date, lacked the precision that would enable manipulations to specifically target these triggers. The aim of this project is to create such tools by developing brain-machine interfaces for detecting and manipulating the triggers associated with psychological disorders.

This project is being developed in collaboration with the other faculty in the Center for Neural Engineering and Prostheses.