Hello my border collie not only barks at us for coughing, sneezing or blowing our nose, but has also been leaving teeth marks on my walls due to seeing shadows or light on it. She drools and pants too or licks the wall . All this is done in front of us, she gets exercised and played with. She has selective hearing too with a terrible recall. She passed her bronze and silver kennel club good citizen a few months ago, since then she has started doing this. She only seems to settle down if l put the lead on her in the house I have to leave the curtains closed when we are going out and cannot switch the Christmas lights on for fear she might chew the wire. she will be 2 in February and l have booked her in to see the vets tomorrow for a check up. Has anybody else come across this ? If so, how did you stop it ?