The name which is given to the use of videos of autistic teens to find out and identify atypical movements as they learn to crawl and walk is known as:
This refers to the fieldwork where a researcher takes records of the various occurrences in nature without any interference.
With this in mind, we can see that the researcher is making use of the naturalistic observation to monitor the autistic teens as they learn to crawl and walk to observe the patterns and formative years.
Read more about naturalistic observation here:
https://brainly.com/question/26355511