Some people report seeing colored glows or halos around other people. This phenomenon is commonly referred to as seeing a person’s aura. But what actually causes someone to see auras? There are a few potential explanations.
The Structure of the Eye
One possible cause of seeing auras is the structure of the eye itself. The human eye contains the following anatomical elements:
| Cornea | Clear outer layer that covers the front of the eye |
| Iris | Colored part of the eye that controls pupil size |
| Pupil | Opening at the center of the iris that allows light in |
| Lens | Transparent structure behind the iris that focuses light |
| Retina | Light-sensitive tissue at the back of the eye that converts light into neural signals |
| Macula | Small central area of the retina containing cone cells for sharp central vision |
| Rod and cone cells | Photoreceptor cells in the retina that detect light and transmit signals to the optic nerve |
| Optic nerve | Nerve that connects the eye to the brain |
The macula, at the center of the retina, contains mostly cone cells and is responsible for central, high-resolution vision. The peripheral retina contains more rod cells and is more sensitive to low light levels. This difference in photoreceptor distribution leads to differences in visual perception from the central versus peripheral visual fields.
Some researchers hypothesize that seeing auras may actually be the result of the peripheral vision detecting faint light that is invisible to the macula. The macula may only see the person you’re looking at, while the peripheral retina detects a dim glow around them that the brain interprets as an aura.
Afterimages
Another possible explanation for seeing auras is afterimages produced by the eye itself. Afterimages are optical illusions that occur when the eye’s photoreceptors retain some visual information after the stimulus has disappeared.
For example, staring briefly at a bright light source can produce an afterimage in the form of a faint halo in your field of vision after looking away. This afterimage fades over the course of a few seconds or minutes as the photoreceptors recover.
If someone stares at a high-contrast boundary just before looking at a person, this could potentially produce an afterimage in the shape of a glow or halo around them that the brain perceives as an aura. Afterimages are a well-documented optical phenomenon, so they likely contribute to some aura sightings.
Brain Cortical Spreading Depression
There is also a neurological explanation for seeing auras. Some neurologists believe they arise from a phenomenon called cortical spreading depression in the visual cortex of the brain.
The visual cortex contains neurons arranged in columns that respond to stimuli from corresponding areas of the visual field. Cortical spreading depression occurs when neuronal and ionic disturbances propagate slowly across the cortex, essentially silencing the neurons briefly as it passes.
This silencing of portions of the visual cortex can produce effects like scintillating scotomas – blind spots with flickering, zigzag edges – that people often see before migraines. If cortical spreading depression propagates partially across the visual cortex, it could potentially distort the cortical representation of a person’s visual field, producing an aura-like effect around them.
Epileptic Discharges
Some forms of epilepsy can also cause people to see auras around others. Simple partial seizures arising from the occipital lobe, which contains the visual cortex, can cause visual hallucinations like auras.
Temporal lobe seizures may also trigger the superior temporal sulcus, which is involved in processing movement and figures, potentially leading to illusory distortions of people’s outlines. Epilepsy-related electrical disturbances in these visual areas of the brain could therefore generate an aura effect.
Brain Blood Flow Changes
Changes in blood flow in the visual cortex may also generate aura perceptions. Neuroimaging studies show that meditation, psychedelics, and other vision-altering practices correlate with increased blood flow in the visual cortex.
The fluid dynamics of blood moving through tiny vessels in the brain is complex. As blood flow changes, the dynamics of nutrients, oxygen, and waste products around neurons and their supporting cells also fluctuates. This can alter their signaling properties, potentially causing subtle perceptual distortions.
Some neuroscientists propose microdynamics of the blood supply could induce effects like auras via minor, temporary changes in cortical tissue excitability and spontaneous neuronal signaling.
Dysfunction in Visual Processing Areas
Dysfunction in parts of the brain involved in visual processing offer additional explanations for aura visions. Candidates include:
| Area | Function |
| V1 | Primary visual cortex, processes basic visual information |
| V2 | Secondary visual cortex, recognizes simple shapes |
| V3 | Tertiary visual cortex, tracks object motion |
| V4 | Color vision area |
| V5 | Motion-processing area |
Dysfunction in any of these areas could potentially cause people to misperceive borders, motion, or colors in their visual field, perhaps seeing a colored glow around objects or figures where none exists.
Minor impairments in visual processing areas could arise from things like micro-seizures, mini-strokes, migraines, tumors, or even psychedelics affecting the visual cortex. If these effects are localized, they may distort only a portion of the visual field, producing aura-like effects.
Synchronized Neural Activity
Another neurological theory behind auras involves synchronized firing of neurons in the visual cortex.
Normally, cortical neurons exhibit complex spiking patterns with highly variable timing. But sometimes groups of neurons spontaneously synchronize their firing due to changes in ion flows and membrane potentials.
This synchronization may occur in localized regions or propagate across larger cortical areas. Researchers find psychedelic compounds like LSD, psilocybin, and mescaline can induce synchronous gamma oscillations across the cortex.
These neurochemicals act on serotonin receptors densely expressed in the visual cortex. The resulting synchronized neuronal activity may alter normal information coding and give rise to aura-like visual disturbances around perceived objects and people.
DMT Release
Naturally occurring DMT in the brain may also generate aura perceptions. DMT or N,N-dimethyltryptamine is a psychedelic compound found in many plants and animals.
Some researchers believe the pineal gland may produce DMT in the human brain, especially in high stress situations or near death. DMT is a powerful psychedelic and a normal part of metabolism, but there is still debate around pineal DMT levels and functions.
Regardless, trace amounts of endogenous DMT could theoretically stimulate serotonin receptors in the visual cortex, inducing a temporary synchronous firing state. This may alter perceptual coding enough to produce visual distortions like halos or auras, especially in dark, calm environments.
Mystical Experiences
Beyond scientific explanations, many believe auras represent spiritual energies or mystical phenomena. The ability to see auras is often considered a special skill or sign of psychic aptitude.
As an electromagnetic being, the aura is thought to reflect the health, mood, power, or other attributes of a person. Aura colors and patterns are interpreted for deeper meanings about the spiritual, emotional, mental, and physical state of the individual.
For those who can see them, auras provide revealing insights into the inner and outer conditions of a person. From this perspective, aura visions arise from attuning one’s mystical perception to subtle energetic fields beyond the ordinary scope of awareness.
Synesthesia
The condition known as synesthesia, where people experience blended sensory perceptions, may also generate auric visions in some individuals.
In synesthesia, sensations like sounds, letters, concepts, or others involuntarily trigger additional sensory experiences such as colors, textures, shapes, or tastes. This neurological condition causes people to consistently perceive consistent, complex sensory fusions.
Some synesthetes with sound-color synesthesia may involuntarily see colored auras around people whose voices evoke certain hues. Similarly, synesthetes with color-texture sensations may see auric shapes and patterns around people due to sound-texture associations.
While synesthesia is rare, it demonstrates how cross-wiring in the brain can automatically fuse sensory perceptions in complex ways that may include auras.
Hypnagogia & Hallucinations
Hypnagogic and hypnopompic hallucinations – imaginary visions at sleep onset and wake-up – could also generate aura perceptions in that twilight state between waking and sleeping.
As the brain enters early sleep stages, the relaxation of conscious control combined with random neural firing can produce vivid imagery and perceptions. Hypnagogic hallucinations often reflect fragmented dream-like mental activity intruding into waking perception.
Similarly, as the brain activates in the morning, incomplete arousal may allow dream mentations to manifest briefly as waking hallucinations. These could include seeing people with luminous auras or halos.
Such transient hallucinatory perceptions may contribute to some aura reports, especially with unsure timing around falling asleep or waking.
Illusory Auras
Research also shows auras can arise from illusory effects related to contrast and afterimages. Experiments that simulate aura viewing conditions can induce aura-like brightness and color distortions via simple visual illusions.
For example, concentrating on a bright object, then looking at a darker uniform background can produce a negative afterimage outline that looks like an aura. Concentrating on a colored patch can induce an illusory halo of complementary color around a gray target.
Such experiments suggest focused concentration combined with looking at high-contrast boundaries between bright and dark, or different colors, can generate optical effects that get misperceived as luminous auras.
Conclusion
In summary, there are many possible scientific and spiritual explanations for seeing auras around people. While auras remain controversial, potential causes span optical illusions, neurological conditions, psychedelic effects, and mystical perceptions of subtle energy fields said to encapsulate living beings.
The many neurological variables involved in processing visual information leave room for individual differences in perceiving luminosity, contrasts, afterimages, and other effects that could become manifest as auric halos. And for those spiritually inclined, auras provide a direct sensory experience of energetic connections between living things.
In the end, the causes of aura perceptions likely include both mundane visual distortions and potentially insightful glimpses beyond ordinary consciousness. As brain science progresses, we may discover more links between neurochemistry, neural information coding, and expansive perceptual experiences hinted at in aura visions.
