the coughing episodes are also episodic, progressively severe and eventually nocturnal. they are initiated by a “ticking sensation” deep in the throat or more typically behind the suprasternal notch. this sensation then causes the patient to cough. the cough is therefore a ‘normal’ response to this ticking sensation rather than an uncontrolled muscular contraction of the diaphragm or intercostal muscles. the coughing episodes can be severe with incontinence, vomiting, visual phosphenes (“seeing stars”), and post-tussive headache. these episodes typically progress from mild to severe over the years and eventually will awaken the patient from sleep. in between episodes, the patient is normal and respiratory examination does not reveal reactive airways disease (asthma) or allergies. the coughing episodes can be triggered by loud or prolonged talking, exercise or the choking episodes described above.