noun, Psychology. 1. Also called operant conditioning, instrumental conditioning. a process of changing behavior by rewarding or punishing a subject each time an action is performed until the subject associates the action with pleasure or distress.
Pertussis is caused by the bacterium Bordetella pertussis. It is an airborne disease which spreads easily through the coughs and sneezes of an infected person. People are infectious to others from the start of symptoms until about three weeks into the coughing fits.
What is pertussis (whooping cough)? Pertussis (also called whooping cough) is a very contagious disease caused by a bacteria called Bordetella pertussis . It can cause severe coughing fits which can affect breathing. After fits of many coughs, a person with pertussis often needs to take a deep breath resulting in a âwhoopingâ sound.