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, also known as whooping cough, is an extremely contagious disease caused by the Bordetella pertussis bacterium. These bacteria produce toxins that paralyze parts of respiratory cells, leading to inflammation in the respiratory tract.