Recently, scientists have discovered a new way to understand brain function in infants and toddlers by examining the brain’s functional signature using fMRI during natural sleep. When considering the study of autism, this method opens considerable doors because it eliminates biases of past studies that only sampled from high-functioning, older populations. This method, referred to as “sleep fMRI,” was first used to map aspects of brain functioning in typically developing infants and toddlers in the early 2000s.
Although the brain’s signal is attenuated during natural sleep in contrast to the awake state, the pattern of activation is surprisingly similar. The original pioneering work demonstrating that sleep fMRI could be successfully used with typically developing infants was conducted by Dehaene-Lambertz and colleagues in 2002. This research was published in the journal, Science. Since that time, researchers at the ACE have used sleep fMRI to examine brain function in toddlers with autism as young as 12 months. See papers by Redcay & Courchesne, 2007 and Pierce, 2011.
There are 4 main steps to the sleep fMRI method developed by the UCSD ACE:
- Parents are instructed to eliminate all naps from their child’s typical routine.
- Parents are asked to keep their child awake while at home and arrive at the scanner 1-hour past their child’s normal bedtime.
- The child either falls asleep during the car ride to the scanner or falls asleep in their parent’s arms at the scanner. Sleep onset time is documented.
- In order to attempt to standardize stages of sleep during scanning, babies are placed on the scanner bed approximately 20 minutes after sleep onset.
The UCSD Autism Center of Excellence has successfully scanned over 300 infants and toddlers with autism between 12-48 months using this method. At this time, we are currently conducting sleep fMRIs on toddlers between the ages of 12-36 months old. If you are interested in participating, please contact the fMRI study coordinator at 858-534-6912.