Age (neuroling.) ; Old age (neuroling.) ; Gesprächsstil; Conversational style ; Communication research ; Physician-patient communication; Doctor-patient-communication ; Restaurant; Business communication; Notruf; Emergency call; Service encounter ; Crisis (psychology) ; Krise (Psychologie) ; Stress (language behavior) ; Old age (reading) ; Old age (speech perception) ; Speaker strategy ; Elderspeak; Gerontolekt; Seniorensprache; Old age (language behavior) ; Language and medicine ; Dysphasia; Aphasia ; Morbus Alzheimer