Which of the following is NOT associated with Vertical Gaze Nystagmus (VGN)?

Vertical Gaze Nystagmus (VGN) is a specific type of involuntary eye movement where the eyes exhibit abnormal oscillations when looking up and down. Certain classes of drugs are known to influence eye movement and can cause VGN.

The correct answer indicates that none of the options listed—narcotic analgesics, CNS stimulants, or hallucinogens—are associated with VGN. While it is important to recognize that various substances can lead to different forms of nystagmus, VGN is primarily associated with substances such as alcohol and certain prescription medications, rather than the ones listed.

Narcotic analgesics typically cause sedation and may induce other forms of nystagmus, but not specifically VGN. CNS stimulants, while they can lead to hyperactivity and increased eye movement, do not generally produce VGN. Hallucinogens can alter perception and may lead to other types of nystagmus, but they too are not strongly correlated with VGN.

Understanding this distinction is essential for accurately identifying the effects of substances during a drug recognition evaluation. Thus, the conclusion is that none of the given drug categories is associated with Vertical Gaze Nystagmus.