What is [[Scopes]] in dispatch() of redux

I am using redux with react. This makes dispatch available as props in component. So when I console.log(this.props) I see following object in log under dispatch key.

[[Scopes]]: Scopes[5]
   0:Closure
   1:Closure
   2:Closure (createThunkMiddleware)
   3:Closure
   4:Global

Can someone explain what is this ?