A female parsons was also that way. She had an apparent stroke when I got her due to stress and was unable to fly for awhile. Each evening she would wait for me to scoop her up in my hand and put her in her nest. Completely at peace. She has since made a full recovery and her clutch hatched this morning.
Birds learn from experience.
New arrivals are at first a little apprehensive but, within a couple weeks are also unaffected by what goes on around them. When you take the time with your birds they become used to having you around. When I first installed an indoor aviary, it was just a wooden frame with plastic bird mesh wrapped around. Escapes were frequent. The escapees always seemed to enjoy sitting on top of one of my aquariums.