Ever experienced a sudden case of hiccups when you were having a hearty laughter session? So what causes those involuntary fits that interrupt your laughter and conversation when they attack you in their full power? Sometimes, when you laugh for an extended period of time, air rushes into your diaphragm because of improper breaths, which forces your body to expel the excessive air in a different way – hiccups. Laughter can also disturb the phrenic nerves, which connect the brain to the diaphragm, by abnormal breathing, which in turn leads to contraction of the diaphragm and eventual hiccups.
