Marijuana impacts cognition and sensory functions.  The impairment is enough to create a serious hazard to driving.  The rate of drivers testing positive for marijuana only in a fatal accident, has doubled in Washington and Colorado since the legalization of marijuana.  Marijuana causes dysfunction in retinal processing.  Marijuana inhibits up to 75% of the visual functions in the lateral geniculate nucleus, the primary brain relay nucleus.  Little is known about what levels of marijuana and its primary ingredients; Cannabidiol (CBD) and Tetrahydrocannabinol (THC), impair functions enough to impact driving.  Further there is no functional test available to law enforcement to support dysfunction even when the blood levels of measured THC is considered to be high enough to impair function.  There is research using functional Magnetic resonance imaging that the visual system has dysfunction with acute and chronic use of marijuana.  This lecture will review the available research related the visual pathway and its relationship to driving and cannabis use.

Course Code:



Denise Valenti, O.D.



AOA Expiration Date:


Related News

What defines the value of care we provide?

Health and vision plans have not adapted and grown with the care we deliver but hold back optometry’s momentum.

How to speak the universal language of care

How to create a bilingual and culturally sensitive practice, why it matters to patients and how it can set you apart from the competition.

Doctors of optometry challenge reasoning behind proposed Eyeglass Rule changes at FTC workshop

The recent workshop heard testimony from various stakeholders on the potential impact that proposed changes to the Eyeglass Rule might have on consumer choice and the burden on the practices of doctors of optometry and ophthalmology, which are already understaffed and saddled with other federal regulation. The Federal Trade Commission will use the feedback to determine whether to go forward with its recommendations.