Hi, my friend who suffers from PD, can get to sleep fine, but if he awakes in the middle of the night he becomes aware of a tension in his neck/shoulders (as if he were holding his head up when in fact it is resting on the pillow). No position seems comfortable and he often has to get up and spend the rest of the night asleep sitting upright in a sofa. Does anyone else have this problem? Or know how what might be done to remedy it? He has tried various different pillows and also raising the top part of the mattress but nothing has really worked so far.