Harry Potter Goblet of Fire, Mad Eye Moody & polyjuice question?

[Louiseranger]

Did the polyjuice potion allow Barty Crouch Jr to impersonate the real Alastor Moody's personality as well as his appearance?

If so, how come in the second Harry Potter when Harry and Ron drink the polyjuice potion to impersonate Goyle and Crabbe, how come their personalities didn't change too? yet it changed for Barty Crouch Jr?

 

[Mufasa]

Barty Crouch jr's personality didnt change. that was his own impersonation of Alastor moody