Changes in intraocular pressure induced by differential forced unilateral nostril breathing, a technique that affects both brain hemisphericity and autonomic activity

Abstract
There is evidence of the central regulation of intraocular pressure, and it has been suggested that vagal tone might be elevated in glaucoma simplex. The nasal cycle, the simultaneous congestion-decongestion response in the nasal cavities, reflects the dynamic lateralization of the autonomic nervous system. Since this lateralization presents with sympathetic activity induced by left brain hemisphere stimulation and parasympathetic activity induced by right hemisphere stimulation, forced unilateral nostril breathing (FUNB) has recently been demonstrated to induce selective contralateral hemispheric stimulation as measured by relative increases in EEG amplitude in the contralateral hemisphere as well as alternating lateralization of plasma catecholamines. Using this functional vagotomy/sympathectomy, we report the novel finding that right hemispheric activation via left FUNB increases intraocular pressure (IOP) by an average of 4.5%, whereas left hemispheric stimulation via right FUNB leads to a significant (25%) decrease in IOP.