College rule is a little different, but has similarities. In college the runner may attempt to advance after turning and heading back to 1st base as long as they have not retouched first base. But, if the runner turns and steps into fair territory beyond 1st baseling extended, they are considered to have committed to going to 2nd base, and if they step into foul territory beyond 1st baselin extended, they are considered to have committed to 1st base.