Fig. 1.

Changes in various parameters during coughing attack evoked by mechanical stimulation (Stim.) of tracheobronchial mucosa in anaesthetized cats, shown schematically. Recordings: CO₂ (%) - tidal CO₂ content; V_T – tidal volume; V̇ – tracheal airflow; P_pl – pleural pressure; EMG_ab – electromyogram of abdominal muscles; EMG_d – electromyogram of diaphragm. Time 1 s. Recordings of tracheal airflow and pleural pressure clearly show that active expiratory efforts produced by expiratory muscles strongly characterize the cough motor pattern (from Korpáš and Tomori 1979).