Visual Phenomenology of the LSD Flashback
Archives of General Psychiatry – August 01, 1983
Source: OpenAlex
Summary
Half of the 123 individuals with a history of LSD use experienced flashbacks lasting five years, compared to none in the 40 control subjects. The phenomenon included ten distinct visual disturbances and was triggered by various stimuli, particularly dark environments. Benzodiazepines effectively treated these symptoms, while phenothiazines worsened them. Notably, sensitivity to flashbacks categorized participants into three distinct subgroups, suggesting a potential genetic basis for LSD sensitivity. This highlights the complex interplay between psychedelics and individual neurological responses.
Abstract
One hundred twenty-three persons with a history of LSD use were studied for the presence of the LSD flashback phenomenon and compared with 40 control subjects. A syndrome emerged that included ten distance visual disturbances. It had lasted for five years in half of the population, was treatable with benzodiazepines, exacerbated by phenothiazines, and precipitated by 19 different stimuli, most commonly emergence into a dark environment. Sensitivity to LSD as determined by flashbacks appears to divide the study sample into three discrete subgroups. There may be a genetic basis to LSD sensitivity.