Artist James Turrell is adamant everyone, even the colour-blind, sees exactly the same thing when they slide into the kaleidoscopic centrepiece of his retrospective The Perceptual Cell.
But visual neuroscientist Trevor Lamb, an emeritus professor in the John Curtin School of Medical Research Eccles School of Neuroscience, says the reality is more complex.
This and other mysteries behind Turrell's exhibition could be revealed on Wednesday night when art and science combine for Let's talk about Perception, a panel discussion at the National Gallery of Australia featuring three ANU researchers in the fields of neuroscience, neuropsychology and the physics of light.
"The big difference between Turrell and virtually all other artists is he is using the illumination to give the experience whereas most conventional painters are using the pigments they put on the artwork," Professor Lamb said.
"He instead is using the light, the illumination; it gives him a completely different pallet and allows him to present very different experiences."
Professor Lamb said Turrell's use of the Ganzfeld effect – when the entire visual field is illuminated uniformly – in many of his works, including the light-filled room Virtuality Squared, plays tricks on the eye.
It's a process he has used in his own research, but without Turrell's flashing stroboscopic lights.
"Our visual system has evolved to cope with the natural world… illuminated by the sun or a cloudy sky and it makes certain assumptions and extracts information about colour and objects," Professor Lamb explains.
"What your visual system is trying to do is eliminate the effect of the illumination so if it's a bluish sunset or a reddish sunset sky the perception you get of colour of a given object pretty much stays the same… it's a remarkable job that our visual system does but there are certain ways you can fool it."
Within the sparse white walls of Turrell's works, without a myriad of surfaces reflecting light in different ways, the visual system struggles to make comparisons across the scene in a phenomenon called colour contrast or colour constancy.
But rather than overwhelm the brain, Professor Lamb said the lights of Turrell's works may be simpler for the brain to process than a normal scene.
The panel discussion with Professor Lamb, emeritus Professor Hans Bachor, and associate professor, Dr Mark Edwards moderated by exhibition curator Lucina Ward will begin at 6pm on Wednesday in the NGA's James O Fairfax Theatre.
Tickets are $20, $15 members/concession, and $5 students with a glass of wine included. Visit https://online.nga.gov.au/eventbookings for bookings.