Researchers are exploring the possible effects of marijuana on vision. The researchers found abnormal changes in the eyes’ retina associated with regular use of cannabis. The researchers aimed to explore the effects of marijuana use on the function of retinal ganglion cells (RGCs). Marijuana is known to act on the central neurotransmission, so studying the RGCs in individuals who regularly use cannabis is of high interest.
Of the 52 participants of the study, 28 were regular cannabis users and the remaining were controls. Based on the results of pattern electroretinography, the researchers found a significant increase of the N95 implicit time in cannabis users. The amplitude and the implicit time of the N95 wave are two parameters used to assess the RGC function.
The authors wrote, “This finding provides evidence for a delay of approximately 10 milliseconds in the transmission of action potentials evoked by the RGCs. As this signal is transmitted along the visual pathway via the optic nerve and lateral geniculate nucleus [a relay center in the thalamus for the visual pathway] to the visual cortex, this anomaly might account for altered vision in regular cannabis users. Our findings may be important from a public health perspective since they could highlight the neurotoxic effects of cannabis use on the central nervous system as a result of how it affects retinal processing.”
“Independent of debates about its legalization, it is necessary to gain more knowledge about the different effects of cannabis so that the public can be informed. Future studies may shed light on the potential consequences of these retinal dysfunctions for visual cortical processing and whether these dysfunctions are permanent or disappear after cannabis withdrawal,” the authors concluded.