Ultrasound could treat psychiatric disorders with adaptive behavioural pattern

Some people diagnosed with a psychiatric disorder believe that engaging in certain rituals will lead to positive outcomes such as attributing a good test result to wearing green, rather than study hours put in – this is known as the “credit assignment” process. Researchers at the University of Plymouth, UK, showed that credit assignment-related brain activity can be safely and quickly disrupted with low-intensity transcranial ultrasound stimulation (TUS).

Currently investigated in animal models, TUS could modulate both brain activity and behaviours related to these credit assignment processes. Because of the ultrasound neuromodulation, the animals’ adaptive behaviour was no longer guided by choice value — meaning that they could not understand that some choices would cause better outcomes — and decision-making was less adaptive in the task.

Credit assignment processes originate in the lateral prefrontal area of the brain; the study also showed that this process remained intact if another brain region (also part of the prefrontal cortex) was stimulated. The findings revealed how task-related brain modulation is specific to stimulation of areas that mediate a certain cognitive process.

Dr. Elsa Fouragnan — UKRI Future Leader Fellow at the University of Plymouth, said, “The brain is like a mosaic [with] multiple parts doing different things. Each part may be linked to a certain behaviour. The challenge is first to know whether this behaviour is causally linked to a certain brain region. Only brain stimulation allows you to answer this question.

“The second challenge is that if you disrupt or modulate one part, then it can affect several others, so we need to understand how brain areas work together, and how they affect each other if one is stimulated or disrupted.”

Dr. Fouragnan added, “The really interesting finding in this study is not only discovering where certain decision-making activities take place, but also how neuromodulation can change these and associated behaviours. We hope that this can pave the way to new studies in humans, particularly in patients experiencing mental health issues.”

Category: Education, Features