Now the idea of a language switch, actually is lived,
had a quite long life in the psychological literature, and
even in the neural science literature with regard to bilingualism.
Where people have this idea that there is some form of a switch that's used to
turn one language on, and turn one language off.
Again that's a very simple metaphor to use but,
I'll use that sort of illustrate the idea.
And that began with Putzel back in the 1920s, where he developed this idea and
has continued to live in the literature including work by a Wilder Penfield,
where he thought of the idea of a switch mechanism, and
then more recently what has been more and
more worked on looking at the nature of control or switching in bilinguals.