me vs. this?

[Charles Hartman]

In a mouseUp handler for a radio-button group called "my group", I  
would have thought I could refer to the hilitedButtonName of the  
group without specifying it any further. But

     answer the hilitedButtonName

doesn't give the right response. Neither does

     answer the hilitedButtonName of this group

It has to be

     answer the hilitedButtonName of group "my group"

or

     answer the hilitedButtonName of me

What I most don't understand (??) is the relation between "me" and  
"this X" when "me" is an instance of type X.

Charles