Psychological & Brain Sciences Researchers Find Unexpected Communication between Brain Regions Involved in Infant Motor Control
When two areas of the brain communicate, their rhythms will often synchronize. One well-known brain rhythm, the theta rhythm, is most closely associated with the hippocampus, a region in the forebrain important for consolidating memories and navigation, among other functions. In experiments with infant rats, the researchers showed for the first time that the hippocampus oscillates in lockstep with the red nucleus, a brain-stem structure that plays a major role in motor control. Importantly, the hippocampus and red nucleus synchronize almost exclusively during REM (active) sleep.
Rats and humans both spend much of their early lives in REM sleep. In human newborns, eight hours of every day is occupied by REM sleep alone. And because rat brains and human brains have the same basic structure, UI researchers believe the same communication, between the same regions, is likely occurring in human infants. They also suspect disruptions to that linkage may contribute to the motor-control problems that often accompany disorders such as autism and schizophrenia.
“Our findings provide a possible route to understanding the early emergence of motor problems in human infants. Because we found that communication between the hippocampus and red nucleus occurred primarily during REM sleep, disrupting normal sleep in early infancy could interfere with the strengthening of the communication links among forebrain and brainstem structures,” says Mark Blumberg, a professor in the UI Department of Psychological and Brain Sciences and corresponding author on the study, published in the journal Current Biology.