When i get choked or cough i get very light headed and everything goes bright.. what could this be?

Vasovagal response: Your autonomic nervous system (ANS) controls virtually all the organs and systems in your body. When you cough, your blood pressure goes very high & activates part of the ans, your vagus nerve to lower your bp. This is known as the vaso vagal response. The vaso-vagal response is caused by excess pns tone which will lower pulse and BP at the same time. The low BP makes you feel dizzy.