When a person cries, especially during intense sobbing, it is common to begin hiccuping shortly after. The medical term for hiccups is singultus, derived from the Latin word singult, meaning “to catch one’s breath while sobbing.” This connection highlights the link between crying and the physical reflex of hiccuping. A hiccup is fundamentally an involuntary spasm of the diaphragm, the large, dome-shaped muscle at the base of the chest cavity. This sudden contraction causes a quick intake of air, which is immediately interrupted by the rapid closure of the vocal cords, producing the characteristic “hic” sound.
The Physical Mechanism: Diaphragm Stress and Irregular Breathing
The respiratory mechanics of crying explain the ensuing hiccups. Normal breathing is a steady, rhythmic process where the diaphragm smoothly contracts downward to pull air in and relaxes upward to push air out. However, sobbing radically disrupts this pattern, causing a series of sharp, irregular, and often uncontrolled intakes of breath.
These forceful, jerky movements place significant mechanical stress on the diaphragm and the intercostal muscles between the ribs. The quick, gasping inhalations associated with deep emotional distress can lead to hyperventilation, causing the person to swallow excess air. This rapid, erratic movement and the swallowed air irritate the diaphragm muscle, forcing it to work against its normal rhythm.
The diaphragm, when irritated, responds by contracting spasmodically, resulting in the hiccup reflex. Crying involves sudden muscular actions in the chest and abdomen, which physically trigger the diaphragm’s involuntary twitch. This mechanical disruption overloads the muscle’s normal function, causing it to misfire.
The Role of the Vagus Nerve
Beyond the direct physical strain, the nervous system provides the neurological pathway that triggers the hiccup reflex during emotional distress. The vagus nerve is the longest and most complex of the cranial nerves, controlling involuntary functions such as heart rate, digestion, and motor control of the diaphragm. It extends from the brainstem down to the abdomen, forming a key part of the reflex arc responsible for hiccups.
Emotional intensity, such as the stress associated with crying, can act as a potent irritant to the vagus nerve. The nerve’s pathway is highly sensitive to disturbances, and strong emotional signals from the brain can overstimulate it. When the vagus nerve becomes irritated, it sends misdirected signals to the diaphragm muscle.
This neurological miscommunication causes the diaphragm to contract suddenly and involuntarily, initiating the hiccup. The vagus nerve carries the signal from the irritated areas back to the brainstem. The emotional shock or stress of crying essentially creates a temporary short circuit in this neural feedback loop, resulting in a physical spasm.
Simple Ways to Stop Crying-Induced Hiccups
To interrupt the hiccup cycle, the most effective approach is to reset the breathing rhythm or stimulate the vagus nerve to override the misfiring signal.
Techniques to Stop Hiccups
- Holding the breath for 10 to 20 seconds allows carbon dioxide to build up in the lungs, which helps relax the diaphragm muscle and interrupt the spasm.
- Practice measured breathing by slowly inhaling and exhaling for a set count, disrupting the erratic pattern caused by crying.
- Stimulate the vagus nerve by slowly sipping very cold water or gargling with ice water. The cold sensation traveling down the esophagus can help calm the irritated nerve branches.
- Pulling the knees up to the chest while seated can compress the diaphragm, helping to physically reset its function.