A potential new brainstem reflex: The oculoglossal phenomenon.

Area of Science:

• Neuroscience
• Clinical Neurology

Background:

• The oculoglossal phenomenon, an involuntary synchronized tongue movement with ipsilateral eye movement, has been observed.
• Understanding its pathway could aid in developing rapid clinical evaluations of the brainstem and potentially establish a new neurological reflex.

Purpose of the Study:

• To describe and propose a conceptual pathway for the oculoglossal phenomenon.
• To investigate the prevalence of this newly observed brainstem phenomenon.

Main Methods:

• Observational study involving 60 participants tested at the National Neuroscience Institute, KFMC, Riyadh.
• Participants were instructed to protrude their tongue and move their eyes horizontally to the side.
• Confirmation of the phenomenon required simultaneous, involuntary tongue movement to the same side as eye deviation. A literature review and pathway proposal were also conducted.

Main Results:

• The oculoglossal reflex was present in 83.3% (50/60) of the subjects.
• A proposed pathway involves projections from the frontal cortex to the paramedian pontine reticular formation, then to the contralateral medial longitudinal fasciculus, and bilaterally to the hypoglossal nuclei.

Conclusions:

• Accurate description and further study could establish the oculoglossal phenomenon as a legitimate reflex.
• This could provide a novel tool for assessing brainstem integrity in neurological examinations.