by Todd | Altered States, Knowledge, Phosphenes, Psychedelic
Think drug-induced hallucinations, and the whirly, spirally, tunnel-vision-like patterns of psychedelic imagery immediately spring to mind. But it’s not just hallucinogenic drugs like LSD, cannabis or mescaline that conjure up these geometric structures. People... by Todd | Phosphenes, Research
We present a model for flicker phosphenes, the spontaneous appearance of geometric patterns in the visual field when a subject is exposed to diffuse flickering light. We suggest that the phenomenon results from the interaction of cortical lateral inhibition with... 
by Todd | Knowledge, Phosphenes
Entoptic hallucination, geometric hallucinations, or phosphenes, are one of the most commonly reported visual effects of psychedelics. Phosphenes are a sensation of light caused by excitation of the retina by mechanical or electrical means. Pressure phosphenes can be... by Todd | Beta Waves, Gamma Waves, Phosphenes, Research, Theta Waves
Form hallucinations can be reliably induced using temporally modulated light within a specific frequency range (15-30Hz). The neural substrates of such states have yet to be established with certainty. Brain activity of 5 “high responders” was recorded as... 
by Todd | Memory, Phosphenes, Research
Our visual system not only mediates information about the visual environment but also is capable of generating pictures/lights of nonexistent visual worlds within the brain as afterimages, illusions, phosphenes, dream pictures, visual hallucination, and visual...