REFLEXES THE CODES OF NEUROLOGY

reflexesneurologytaskindumankapak21432

REFLEXES IN DISORDERS OF CONSCIOUSNESS

İpek Güngör Doğan

Health Sciences University, Prof. Dr. İlhan Varank Sancaktepe Training and Research Hospital, Department of Neurology, İstanbul, Türkiye

Güngör Doğan İ. Reflexes in Disorders of Consciousness. In: Duman T, editor. Reflexes The Codes of Neurology. 1st ed. Ankara: Türkiye Klinikleri; 2025. p.279-290.

ABSTRACT

Reflex examination is a cornerstone of neurological assessment, providing crucial insights into the localization and pathophysiological mechanisms of central and peripheral nervous system disorders. This review discusses the diagnostic and prognostic significance of reflex evaluation in disorders of consciousness (DoC) such as coma, unresponsive wakefulness syndrome (uWS), minimally conscious state (MCS), and locked-in syndrome. Reflex patterns play a vital role in distinguishing between metabolic and structural causes of coma, localizing lesions, and identifying life-threatening conditions like uncal herniation or brain death. Reflexes, such as pupillary light, corneal, oculocephalic, oculovestibular, pharyngeal and tracheal reflexes, are central to diagnosing brain death, where their absence confirms irreversible brainstem dysfunction. Reflex examination also aids in transient loss of consciousness, including syncope and epileptic seizures, where reflex abnormalities provide insights into underlying autonomic or cortical disruptions. Furthermore, the evaluation of reflexes in conditions like locked-in syndrome highlights preserved brainstem function despite profound motor deficits. Reflex patterns can differentiate DoC from other conditions and guide therapeutic interventions. This review underscores the importance of systematically assessing reflexes to improve diagnostic accuracy, enhance localization of lesions, and ensure better clinical decision-making in acute and chronic neurological conditions.

Keywords: Disorders of consciousness; Reflex syncope; Coma; Brainstem reflexes; Brain death; Lazarus reflex

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