Schizophrenia patients have an impaired ability to imitate, and this may be one of the main reasons for their difficulties with social interaction, according to a brain-mapping study conducted by neuroscientists at Vanderbilt University.
The study, published in the American Journal of Psychiatry, suggests that when patients with schizophrenia were asked to imitate simple hand movements, their brains showed abnormal brain activity in the “imitating area” of the brain.
The new study is the first to use functional magnetic resonance imaging to examine the brain activity of schizophrenia patients while performing basic imitation tasks.
“The fact that patients with schizophrenia show abnormal brain activity when they imitate simple hand gestures is important because action imitation is a primary building block of social abilities,” said first author Katharine Thakkar, Ph.D., who conducted much of the research while completing her doctoral program at Vanderbilt and is now a postdoctoral fellow at the University Medical Center in the Dutch city of Tutrecht.
“The ability to imitate is present early in life and is crucial for learning how to navigate the social world. According to current theory, covert imitation is also the most fundamental way that we understand the intentions and feelings of other people.”
One of the main obstacles to recovery for patients with schizophrenia is their profound and enduring difficulty with social interactions, which makes it hard for them to have relationships or maintain employment.
“As people with schizophrenia commonly have major social problems, understanding their origin, both neurobiological and behavioral, is critically important,” said Philip D. Harvey, Ph.D., professor of psychiatry and behavioral sciences at the University of Miami Miller School of Medicine.
“While study of the activation of the brain while observing versus imitating hand movements may seem too specific to be relevant, it is actually targeting a critical learning process with specific relevance to social functioning.”
In schizophrenia, the brain network involved in imitation seems to be less specialized for social information, said study director Sohee Park, Ph.D., Gertrude Conaway Vanderbilt Chair of Psychology.
“The mirror neuron system raises the question of agency,” Park said.
“If the same group of neurons fire when I am writing and when I watch you writing, how do I know who is doing the writing? But we are almost always certain of who is doing what. Our research implicates the role of this network in individuals with schizophrenia who frequently have serious problems determining agency.”
Since the disorder appears to be a matter of improperly tuned brain circuitry, Park does not hold out much hope to find a drug treatment.
“No one pill can do the job,” Park said. Instead, she sees greater promise in developing training methods to improve schizophrenia sufferers’ basic cognitive skills.
Source: Vanderbilt University