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.
Pertussis is an infection that causes severe coughing. The bacteria that causes the infection is called Bordetella pertussis. Pertussis is also called âwhooping coughâ because of the âwhoop-likeâ sound that can be heard, when someone who has it breathes in air.