What type of nystagmus occurs when the eyes gaze upward at maximum elevation?

Vertical gaze nystagmus is characterized by involuntary eye movements that occur when the eyes are directed upward or downward, particularly when gazing upward at maximum elevation. This phenomenon can be clinically observed and is often associated with certain conditions, including the impairment of the central nervous system or the influence of specific drugs, such as CNS depressants.

In the context of law enforcement, understanding vertical gaze nystagmus is crucial during field sobriety testing, as it can indicate potential intoxication or other impairments. The ability to recognize and differentiate between horizontal and vertical gaze nystagmus may assist officers in making informed decisions during DUI investigations. The other types of nystagmus mentioned, such as horizontal gaze nystagmus, primarily present with eye movements in a side-to-side manner, which is distinct from the upward focus associated with vertical gaze nystagmus. Resting nystagmus and diagonal nystagmus also refer to different types of involuntary eye movements that do not apply directly to the upward gaze scenario described in the question. This understanding underlines the significance of recognizing the specific characteristics of each type of nystagmus in real-world applications.