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 acute infection of the respiratory tract caused by Bordetella pertussis bacteria. Only humans can be affected by this disease. Transmission occurs through direct contact with respiratory droplets spread during coughs and sneezes from an infected person. Symptoms begin with a mild respiratory illness then progresses to prolonged cough episodes with the characteristic whoop or which end in vomiting.