True or False: Any drug that will cause HGN will also cause VGN if taken in high enough doses.

The statement is true because Horizontal Gaze Nystagmus (HGN) and Vertical Gaze Nystagmus (VGN) can both be caused by substances that affect the central nervous system. HGN is often associated with depressants and certain types of drugs, while VGN can occur with higher doses of similar substances. Typically, drugs that impair the vestibular system and cause a disruption in normal eye movement can lead to both forms of nystagmus when taken in sufficient amounts.

Therefore, if a drug is known to induce HGN, escalating the dose can likely trigger VGN as the drug's effects intensify, affecting the coordination of eye movements even further. This relationship indicates a fundamental aspect of how certain categories of drugs function within the nervous system and their potential to provoke various signs when dosages are increased.