Functional Neuroimaging of Psychopharmacologic Treatment for Autism

Lay Summary

fMRI Imaging May Reveal How Medication Modifies Repetitive Behaviors in Autism

Researchers will use fMRI imaging in high-functioning adults with autism to explore whether the drug Citalopram reduces their repetitive behaviors by stimulating brain circuits in frontal brain regions. The results may lead to the development of improved drugs to fully prevent this behavioral aspect of autism.

A hallmark of autism is engaging in pervasive repetitive behaviors.  While prior fMRI studies have defined neural circuits that are involved in a range of autism behaviors, research to date has not defined how current medications work to try to alleviate some of these symptomatic behaviors.  The UNC investigators’ prior fMRI studies have shown that the brain’s frontostriatal areas are under-activated during certain repetitive behaviors.

They now will use fMRI to see whether Citalopram treatment helps to alleviate repetitive behaviors by activating neural circuits in the frontostraitum. Repetitive behaviors and executive function abilities will be assessed in 18 high-functioning adults with autism who have been medication-free for three months, as they undertake specific tasks in the fMRI scanner.  After three months of Citalopram treatment, the adults will be retested to see whether the medication is associated with reduced repetitive behaviors and with increased frontostriatal activation. Participants’ neural activation levels will be compared to those of healthy study participants to determine whether even greater stimulation is needed to approach normal activation levels.

Significance:  The results may characterize how Citalopram activates specific neural circuitry to alleviate repetitive behaviors. Moreover, if circuit activation achieved is found to be less than normal, the findings might lead to the development of more potent therapies that stimulate this circuitry more fully to eradicate or prevent this manifestation of autism.