“I would describe ‘fundie baby voice’ as a woman’s voice that is higher than average in both pitch and breathiness,” said Kathryn Cunningham, a vocologist and assistant professor of theatre and head of acting at the University of Tennessee, Knoxville. “While the average woman’s voice is higher-pitched than the average man’s due to a combination of anatomical and social factors, some women who speak this way seem to be intentionally placing their voices higher than their natural pitch range in order to convey submission to male authority and childlike innocence.”

This assistant professor Kathryn Cunningham answers your question concerning women’s psychology I think.