What is the research about?

Doctors and scientists have long believed that girls with Rett show typical development until they begin to lose speech and the use of their hands. The loss of these abilities, termed “regression,” and the slowing of head growth were thought to signal the onset of the condition. This research study looked at whether or not there are problems with speech and language use prior to regression, which would suggest that the condition has a much earlier onset.

What did the researchers do?

The researchers obtained videos of the girls made prior to the onset of their symptoms and their diagnosis. The researchers were able to use the videos of 15 children, 10 of whom would go on to be diagnosed with typical Rett and 5 who had the preserved speech type. The videos had been made of each child between birth and age 2, when they usually would have reached specific language milestones. These milestones are babbling, making word-like sounds, combining words, and using meaningful gestures. All the videos showed each child playing, taking part in their daily routines, or on special occasions, like birthday parties.

What did the researchers find?

All of the girls had speech and language problems and unusual gestures as they grew. While most of the girls (12/15) babbled and cooed as infants, they also showed unusual speech behaviours. For example, instead of breathing out, they would draw in their breath to produce sounds. They also made high-pitched crying noises. As they grew, more and more of them failed to reach typical speech and language milestones, or they did so and then developed no further in this area. Once they had reached the toddler stage at age 2, only 1 of 15 was able to put together two or more words, as would be expected in a typically developing child.

Take home message

This study suggests that the onset of Rett is not at the time of regression. Instead, there are distinct patterns of language and nonverbal communication problems evident soon after birth. It suggests that these symptoms could be specific to Rett and might be used to make an earlier diagnosis than is possible currently.


The original Research Report was written by P.B. Marschik and colleagues and was published in Research In Developmental Disabilities. 2013.