biostudies-literatureUnknown18(4)Amaya IALumenate Growth LtdFlicker light stimulation (FLS) uses stroboscopic light on closed eyes to induce transient visual hallucinatory phenomena, such as the perception of geometric patterns, motion, and colours. It remains an open question where the neural correlates of these hallucinatory experiences emerge along the visual pathway. To allow future testing of suggested underlying mechanisms (e.g., changes in functional connectivity, neural entrainment), we sought to systematically characterise the effects of frequency (3 Hz, 8 Hz, 10 Hz and 18 Hz) and rhythmicity (rhythmic and arrhythmic conditions) on flicker-induced subjective experiences. Using a novel questionnaire, we found that flicker frequency and rhythmicity significantly influenced the degree to which participants experienced simple visual hallucinatPloS onee0284271https://www.ebi.ac.uk/biostudies/studies/S-EPMC10089352biostudies-literatureEffect of frequency and rhythmicity on flicker light-induced hallucinatory phenomena.PMC10089352Amaya IABehrens NSchwartzman DJSchmidt TTHewitt TfalseEffect of frequency and rhythmicity on flicker light-induced hallucinatory phenomena.Flicker light stimulation (FLS) uses stroboscopic light on closed eyes to induce transient visual hallucinatory phenomena, such as the perception of geometric patterns, motion, and colours. It remains an open question where the neural correlates of these hallucinatory experiences emerge along the visual pathway. To allow future testing of suggested underlying mechanisms (e.g., changes in functional connectivity, neural entrainment), we sought to systematically characterise the effects of frequency (3 Hz, 8 Hz, 10 Hz and 18 Hz) and rhythmicity (rhythmic and arrhythmic conditions) on flicker-induced subjective experiences. Using a novel questionnaire, we found that flicker frequency and rhythmicity significantly influenced the degree to which participants experienced simple visual hallucinat2023-01-01T00:00:00Z20232025-07-11T03:03:54.362Z2025-04-06T15:35:36.678ZS-EPMC100893523704039210.1371/journal.pone.0284271