This post explores six perceptual phenomena that illuminate how we see, perceive time, and experience awareness — both in daily life and in meditation.
Flash lag effect
The flash-lag effect is a visual illusion where a moving object and a briefly flashed stationary object are physically aligned at the same moment, but observers consistently perceive the moving object as being ahead of the flashed one.
This illusion reveals something fundamental about how our brain processes visual information: there’s a temporal lag in how we perceive stationary versus moving objects, likely because our visual system needs time to register and process the flash, while it can predict or extrapolate the position of continuously moving objects. The effect offers insights into the neural mechanisms underlying motion perception and the brain’s attempts to compensate for processing delays.
How it relates to my practise
- Insight meditation practices help me to observe directly how the perception of “now” is already a prediction rather than direct experience, in the same way flash lag effect does
- Wonder if I’m experiencing the same predictive mechanisms that cause the flash-lag effect when I notice my mind anticipating the next breath or jumping ahead during meditation
Key researchers
- David & Romi Nijhawan
- David Whitney & Ikuya Murakami
- Kuno Kirschfeld
- Dale Purves
Motion-Induced Blindness
A striking visual phenomenon where highly visible stationary objects spontaneously disappear from conscious awareness when viewed against a moving background pattern, even though they remain physically present and the eyes are fixated on them.
Typically, brightly colored dots superimposed on rotating crosses or drifting patterns will perceptually vanish for a few seconds before reappearing, often cycling multiple times. The illusion reveals how motion processing actively suppresses awareness of stationary targets, demonstrating that what we consciously see is not simply determined by what’s on our retinas but is actively constructed by the brain.
How it relates to my practise
- Reminds me of meditating on the bindu (centre point) in mandala/yantra I have at home
- Staring at this gif takes me to present awareness & it’s very easy to fall into a meditative state
Key researchers
- Yoram Bonneh
- Dov Sagi
- Nikos Logothetis
- Sheng He
- Jeremy Wolfe
- Tomas Knapen
- Michael Bach
Key artists
- Carsten Nicolai/Alva Noto
- Bridget Riley
- Michael Murphy
Reversal of temporal order judgment
A perceptual phenomenon where people consistently misjudge the sequence in which two events actually occurred, perceiving them in the opposite order.
This typically happens when comparing events across different sensory modalities (like vision and touch) or when one stimulus requires more processing time than another – for example, people often perceive a touch as occurring before a visual stimulus even when the visual stimulus actually came first, because touch signals can reach the brain more quickly.
Classic example: Imagine watching a light bulb while simultaneously touching a button. The light flashes at exactly the same moment you press the button. However, you might perceive that you pressed the button before the light flashed, even though they were perfectly synchronised. Now, if experimenters actually make the light flash slightly before you press the button (say, 50-100 milliseconds earlier), you might finally perceive them as simultaneous. This is the reversal — the light needs to physically occur first for you to perceive it as happening at the same time as the touch.
How it relates to my practise
- Insight meditation: Systematically observing bodily sensations, thoughts, and emotions to gain direct insight into impermanence, unsatisfactoriness, and non-self.
- Noting practice: Mentally labelling experiences as they occur (“thinking,” “feeling,” “hearing”) to develop clear awareness of how phenomena constantly arise and dissolve.
Key researchers
- Francisco Varela
- Marc Wittmann
- David Eagleman
- Shin’ya Nishida and Katsumi Watanabe
- Charles Spence
Dark retreats
A dark retreat is a practice where individuals spend an extended period — typically ranging from a few days to several weeks — in complete darkness, usually in a specially designed room or facility with no light exposure whatsoever.
Practitioners often report experiencing spontaneous luminous visions or light phenomena that arise naturally without any intentional visualisation or mental fabrication. These include:
- Thigle/nimitta: spontaneously appearing luminous spheres, dots, or orbs of light in various colours
- Geometric patterns: mandalas, intricate lattices, or sacred geometric forms
- Rainbow lights: streams or networks of coloured light
What distinguishes these from ordinary mental imagery or hallucinations, according to the tradition, is their luminous, self-illuminating quality and the sense that they arise effortlessly from the nature of awareness itself rather than being constructed by the conceptual mind.
How it relates to my practise
- I’ve witnessed nimitta lights in deep meditation/retreats: beautiful, vivid mental phenomena which look like glowing spheres or sparkling dots in the minds eye
- Rainbow light guided meditation on chakras & auric field
- James Turrell’s dark space ‘Aqua Oscura’ at Tremenheere Garden in Cornwall
- Speaking to Tom about his experience on dark retreat – he said he had no concept of time
- Rupert Spira’s meditations:
- Meditating on the mandala/yantra at home
Key researchers
- Holger Kalweit
- David Luke
- Melanie Challenger
- Heinrich Klüver
- Chögyal Namkhai Norbu
- Tenzin Wangyal Rinpoche
Ganzfeld effect
The Ganzfeld effect occurs when a person is exposed to uniform, unstructured sensory stimulation — typically a featureless visual field created by wearing halved ping-pong balls over the eyes with coloured light, or staring into fog. Within minutes, deprived of meaningful visual patterns, the brain begins generating its own spontaneous perceptual experiences: people report seeing colours, geometric patterns, hallucinations, or experiencing complete visual “blank out.”
This demonstrates that our perceptual system requires variation and contrast to function — when input becomes completely uniform, the visual system creates its own content, similar to visual deprivation effects in darkness.
How it relates to my practise
- Visiting James Turrell’s immersive space at Copenhagen Contemporary
- Ajna light therapy sessions in Battersea
- Dream machine in Woolwich
- Reminds me of being in Yayou Kasuma & Olafur Eliasson spaces at the Tate
Key researchers
- Wolfgang Metzger
- Charles Honorton
- James Cutting
- Psychophysics researchers
Key artists
- James Turrell
- Doug Wheeler
- Olafur Eliasson
- Ann Veronica Janssens
- Light & Space movement artists
Troxler’s fading (Troxler effect)
A perceptual phenomenon where stationary objects in peripheral vision gradually fade from awareness and disappear when you maintain steady fixation on a central point. The effect occurs because our visual system is designed to detect change and motion—neurons adapt to unchanging stimuli and reduce their response over time, causing static peripheral objects to vanish from conscious perception even though they remain physically present.
This demonstrates a fundamental principle of visual processing: our brains prioritise detecting changes in the environment over maintaining awareness of constant, unchanging features, essentially filtering out stable background information to focus on what’s new or moving.
How it relates to my practise
- Meditation on bindu of the yantra/mandala
- Experiencing fractals whilst holding ‘samyana’ on a leaf, post retreat (3D > 5D)
Key researchers
- Ignaz Paul Vital Troxler
- Vilayanur S. Ramachandran & Richard Gregory
- Lothar Spillmann
- Peter De Weerd
- Nikos Logothetis & David Leopold
- Derek Arnold
Key artists
- Victor Vasarely
- Jesus Rafael Soto
- Carlos Cruz-Diez
Reflections & Learnings
There were a couple of “aha” moments when putting this post together:
- The positive correlation between the visual dots/crosses in the scientific phenomena and bindu/nimitta/yantra found in eastern spiritual traditions
- Consistency of colours/aesthetics in the images on this post are very much my vibe and in tune with my Frieze references
- Perceptual phenomena I found most interesting were: motion induced blindness; Troxler’s fading; dark spaces & the effect they can have; Ganzfeld effect
Next steps
Research and explore in more detail:
- Motion-induced blindness
- Troxler’s fading
- Dark spaces and their perceptual effects
- Ganzfeld effect
- Bindu, yantras & mandalas
This includes investigating key researchers and artists in each area, and using my sketchbook to annotate and illustrate how I might develop these phenomena further in my practice.