Seeing Stars, Under the Influence of Phosphenes
The nature of sight and its modern neuroscience counterparts
Humans are born investigators, our first experiments conducted with the most intimate instrument we possess: our own body. Part of childhood is discovering yourself as much as your surroundings. What happens when the hand reaches out to the burning stove, how far can you bend your leg, and just how thick is your skin? Such fascinating questions usually wither away as time passes, and school starts to reintroduce you, the naive child, to the body you navigate.
Yet, these small, personal experiments hold the seeds of something far greater. They reflect a fundamental human impulse to make sense of the world, starting from what we know best — our own experience. Centuries ago, this self-reflexive questioning did not always fade into textbooks; instead, it persisted and contributed to scientific study, art, cinema, and philosophy. From the abstract patterns we see behind closed eyes to the profound mysteries of vision and consciousness, our body’s quirks showed the potential to serve as windows into bigger questions and possible truths.
It often circulates that the human body is an active component of life. It moves, thinks, acts, and is vocal about its presence. When it is going to be the subject of study, it becomes presumably clear what that study would entail (psychology, psychiatry, or medicine). Something easily overlooked is the human body as a mediator — a tool that connects our internal experience to the external world, offering profound insights when approached with curiosity and care.
One winter night in 1666, Isaac Newton did something grimacing, yet equally fascinating, in the history of optical science. He bravely self-experimented by taking a bodkin (a long blunt needle) and carefully inserting it between his eye and bone, pressing just hard enough until he saw “.” This act was more than mere reckless curiosity or to demonstrate shock value; it belonged to a centuries-long ancient mystery about vision and light, and he would be the one to help resurface its study.
Seeing phosphenes (coined by Henri Savigny), or “stars” as they are more commonly used, is to experience visual phenomena that give the impression of seeing light in various shapes and patterns (circles, dots, squiggles, etc.) when one’s eyes are closed, even though there is not an actual light source present, or when you have low blood pressure. Derived from the Greek words phos (light) and phainen (to show), the phenomena also explains what is called “the prisoner’s cinema,” when a “light show” or a hallucination appears “.”
A comprehensive study of phosphenes actually reveals more than a quirk of the human body; there is a fundamental trajectory of its documentation where ancient philosophical intuitions about the nature of sight and its modern neuroscience counterparts illustrate the human imagination in its most fundamental form. We see and use what we know. And what we know is usually what we experience ourselves. The human body is a tool in which endless potential and sources are hidden, we have been discovering them for centuries. What we witness, even the most abstract and minuscule phenomena, has the capacity to lend itself to timeless knowledge — to art, cinema, consciousness, philosophy, and the mind and brain.
Ancient Visions and Theories of Sight
The earliest documented study of phosphenes emerges from Ancient Greek investigations of vision and optics in the 4th century BC. Plato was “,” suggesting that eyes projected rays of light like a flashlight, illuminating objects in front of them. The emission (or extramission) theory proposed that when something blocked these “eye rays,” the result was darkness.
While Empedocles had discussed elements and fire in relation to vision, conceiving the eye as containing an internal fire that “,” it was Plato who developed this into a systematic theory of vision. The eye was conceived as functioning similarly to mechanical devices that emit light, like a torch. This early understanding of phosphenes played a crucial role in shaping how ancient philosophers conceptualized the very nature of vision and light itself.
This human-centric understanding persisted in Western thought until introduced his Book of Optics in the 10th century, with the correct explanation that vision occurs when light reflects from an object into one’s eyes. Alhazen, using phosphene experiences to directly challenge the emission theory, marks one of the first instances where subjective experience was deliberately deployed to test scientific hypotheses. His work demonstrated that phosphenes appeared only under specific conditions of pressure or stimulation, suggesting they were generated by the eye itself rather than being evidence of an internal fire.
Enlightenment Experiments and Optical Wonders
The Renaissance marked a pivotal shift in how humans approached their own sensory experiences, as with everything else. If ancient philosophers began with broad theories about vision and light, the new empiricists started with what they could directly observe and test, even if it meant sticking needles into their eyes. Newton’s bold method of study exemplified this approach and took something that arose from a curiosity as fundamental as a childlike wonder to substantiate it within systematic research. It was a return to basic experience, but now armed with the tools of scientific inquiry.
Jan Evangelista Purkyně, a Czech anatomist and physiologist, was the first person to publish a detailed account of phosphene study, in 1819. Purkyně cataloged : pressure-induced geometric patterns, blood vessel shadows in the retina, electrical stimulation effects, and patterns from mechanical impact, among others. His analyses of such patterns (like honeycomb structures and radiating lines) were precise and calculated. He specifically noted how the “background generally consisted of fine quadrangles in regular array, on which there were either stars with eight rays, or dark or bright rhombs with vertical and horizontal diagonals. and the patterns were surrounded by alternately bright and dark bands.” While admirable in nature, not everyone documented them with such regularity — including Hermann von Helmholtz.
Helmholtz recorded the phosphenes as complex mazes, mossy surfaces, and intricate leaves. Instead of the routine and form of its patterns, he experimented more with the structure of the light show. In his , Helmholtz discovered that applying pressure to specific points on the eye produced predictable phosphene patterns in opposite regions of the visual field. He meticulously mapped how pressure near the temple created phosphenes near the nose, each with distinct characteristics: a bright center surrounded by dark and bright rings.
Such spatial mapping helped establish that the retina processed visual information in an organized, systematic way. Helmholtz also documented how phosphenes changed under different conditions: they dimmed when looking left with the right eye closed, remained elusive in foveal vision, and transformed dramatically with varying light conditions. Gradually, the phosphenes cemented themselves as an effective tool in further understanding the mechanical and physiological architecture of the eye. Once again underlining the intrinsic relationship one has with their own body and the scientific ground it is a part of, a small and simple observation gradually lent itself to an eye-opening (or closing) outcome.
Neural Pathways and Modern Science
Modern neuroscience evidently built on its predecessors. When Otfrid Foerster’s detailed how, by electrically stimulating precise points in the visual cortex, he could reliably produce specific phosphene patterns and showed these internal lights weren’t random but mapped directly onto our neural architecture.
Yet another influential blow came from the German electrical engineer, Max Knoll. Studying at Munich’s Technische Universitat in the 1950s, Knoll further substantiated these findings by , and finding out that electrical pulses matching brain wave frequencies (5–40 Hz) were most effective at producing phosphenes. He identified 15 distinct geometric patterns that remained consistent for each individual even after six months. Remarkably, these patterns became more elaborate when subjects were given small doses of hallucinogenic substances like LSD, suggesting deeper connections between neural architecture and altered states of consciousness.
In 2008, Hungarian neuroscientist István Bókkon recontextualized phosphenes in science through a biopsychophysical . His research demonstrated that these phenomena arise from the intrinsic perception of ultraweak bioluminescent photon emission in the visual system. These biophotons — particles of light generated by cellular activity — emerge when cells use oxygen to produce energy. During this process, cells naturally generate reactive molecules containing oxygen and nitrogen that can emit tiny amounts of light.
This discovery helped explain why activities that affect cellular energy production, from pressure to electrical stimulation, can trigger phosphenes. The brain processes these internal light sources through non-visual neuronal opsins and photosensitive biomolecules, just as it does external light.
The technicality of the matter is endless and ever-expanding. While certain facts are crucial to properly ground the concept, even in the minds of the layman, the scientific and intuitive trajectory of it is still the most thought-provoking part, especially in consciousness studies.
When Knoll that tiny doses of LSD (as little as 10 micrograms) dramatically enhanced the complexity of electrically induced phosphenes, he opened a fascinating avenue of investigation: might these internal lights be literal windows into our consciousness? If not, what are they actually alluding to, deceiving the capable eye? When people enter altered states, whether through meditation, sensory deprivation, or psychedelics, they consistently seeing geometric patterns that match phosphene patterns, suggesting these aren’t mere “hallucinations” but yet another way to see those infamous stars.
The connection runs deeper still. Unlike ordinary vision, which involves processing external light, phosphenes emerge from within the brain itself. As we see these internally generated patterns during different states of consciousness, from wakeful meditation to psychedelic journeys, we might be witnessing the basic building blocks of visual consciousness. Just as ancient traditions used these experiences as gateways to understanding mind and perception, modern neuroscience is beginning to see phosphenes as a unique bridge between objective neural mechanisms and subjective conscious experience.
Psychedelic Art and Cultural Constellations
Naturally, anything related to the human finds its way to artistic expression and culture. The geometric patterns documented in phosphene research surface across various artworks and artifacts.
In the psychedelic movement of the 1960s, artists directly engaged with these internal visions. , the famous Spanish-American artist, pioneered the use of vibrating colors in his concert posters, deliberately using complementary hues of equal value to recreate the pulsing patterns people report during altered states (coinciding with the experience of phosphenes). ’s characteristic typography, with its fluid, melting forms, also mirrored the organic geometries produced beneath our eyelids. The styles are grouped into their psychedelic origins, but they were traced from a place much deeper within.
One can also trace them in architecture, if careful. They emerge in the spiraling motifs of Aboriginal art, the intricate geometric designs of Islamic mosques like the Shah Mosque of Isfahan, and the precise mathematical patterns of Gothic cathedral rose windows. These same forms surface in prehistoric art, from the zigzag patterns of European Paleolithic caves to the concentric circles of Australian Aboriginal petroglyphs.
Brion Gysin’s 1959 , created in collaboration with William Burroughs, was specifically designed to produce flicker-induced phosphenes through spinning light patterns. James Whitney’s 1966 film attempted to recreate these inner visions through animation, while Jordan Belson’s (1961) drew direct inspiration from phosphene-esque patterns. Even further manifestations can be traced in contemporary digital artists as well, such as in the algorithmic animations of or the immersive light installations of . These examples only scratch the surface, since such patterns and inspirations echo across countless other artistic and cultural forms throughout decades and centuries.
Creativity and imagination are boundless, serving purposes beyond artistic innovations. Essentially, such examples are attempts — whether voluntary or not — to externalize a shared internal visual experience so familiar and usual that the “trend” always catches on. It’s a humbling realization and a timelessly mystifying revelation: one can engage in an act so seemingly mundane, be deeply intrigued, and yet still not completely grasp the potential of what they are actually witnessing.
To take a step back and reevaluate the simple things — the small curiosities — can lead to a self-reflexive, historical, and philosophically challenging journey through the history of perception and being. What it means to be human is a fundamentally difficult question to answer in a way that satisfies everyone, but digging deep into the quirks of the one tool we wholly possess, ourselves, can resituate the inquiry into a context that is more meaningful and [literally] accessible.
To answer questions of the greatest scale and utmost significance, sometimes a path led by the minuscule is most effective, like the thought of an internal glow. It can urge us to rethink anything potentially deemed regular or even boring and to see it differently under an external, truly illuminating light.
It is often advised, and frequently observed, that we start from what we know best. We tend to momentarily lose ourselves in human-centric thoughts, only to evolve into more modest perspectives. Perhaps we were born selfish, or perhaps we adopted the mindset to survive. Either way, science, and imagination humbled us, allowing us to use these concepts to situate ourselves in this world through scientific study, art, and philosophy — even though we all once thought we were just seeing stars.
