DAVIS, Calif., Dec. 6 (UPI) -- U.S. researchers say they've determined brain wave changes in adolescence are related to age and might be associated with synaptic pruning.
The University of California-Davis scientists note that during childhood, the brain has many synapses but, during adolescence, the brain eliminates many synaptic connections, a process known as synaptic pruning.
Previous studies found a steep decline in sleep slow wave activity, the delta wave, during adolescence. The authors hypothesized the decline is caused by age-programmed synaptic pruning.
The study followed two groups of children during the course of two years: 31 children were 9 years old at the beginning of the study; 38 were 12 years old.
The researchers used an in-home electroencephalograph to record the children's brain activity during sleep.
They found delta wave intensity across the 9-to-11 age group was unchanged and the same for girls and boys. But among the 12- to-14-year-old group, the scientists discovered a 25 percent decline in delta wave intensity that was related to age, but unrelated to physical growth and sexual maturation
The study appears in the December issue of the American Journal of Physiology-Regulatory, Integrative and Comparative Physiology.
