Mark W Leitman
Noxious stimuli could elicit a response of fear or disgust. Fear is a sympathetic response which causes increasing sensory awareness, while disgust is parasympathetic, resulting in sensory avoidance. A deep in-breath is already known to be triggered by fear. This study shows this deep inhalation suppressed the spontaneous eyelid blink in 93% of 255 subjects and suppressed scanning eye movement of the orienting reflex in 92% of 80 people. Even the normal in-breath suppressed the blink in most instances. Both of these responses serve to increase focus with uninterrupted visualization of an imminent danger. Inhalation’s suppression of blinking could prove useful in photography and sports. This study shows that wary concentration on a threatening stimulus coming toward the eye causes an opening of the mouth. When putting on eye make-up, 91% of 45 women admitted to opening their mouths. This response likely evolved to satisfy the brain and skeletal muscle’s increased oxygen demand needed for concentration and possible fight-or-flight. Blinking is already known to be associated with disgust. Over 92% of 80 subjects found it difficult to take a diaphragmatic in-breath while blinking rapidly. Airborne contaminants often irritate the eye and this blinking reflex likely serves to protect the lungs. It is known that increased blinking occurs when viewing disgusting images, e.g., rotting food and tasting sour or bitter foods. When subjects intentionally increased their rate of blinking, 95% of 38 subjects found it difficult to swallow. A feedback loop found in this study was that the deep in-breath suppressed spontaneous blinking, while rapid blinking suppressed in-breathing.
