Why does Bromden laugh at himself? Why does Bromden talk to Mac? What does he want to say to Mac? Why does he want to touch him?

Bromden laighs at himself because he blows his "unable to talk" cover over a piece of Juicy Fruit gum. He wants to talk to McMurphy because he wants to sign up for the fishing trip..... he wants to touch him because for the first time in years he feels an emotional tug toward another human being.