here is some information on the "freezing" effect that you may be seeing. please get in touch with your mom's doctor and discuss this behavior with him to determine exactly what's going on and needs to be done. the webmd answers staff
my mother has parkinson's disease. she has been having episodes of unresponsiveness. are these related to parkinson's? . these episodes vary in their duration. she just stares and does not respond to stimuli verbal or physical. it has been suggested these are "freezing" episodes but i am not familiar with "brain freezing" associated with parkinson's. thank you for your assistance.