The latest work of art to be displayed at the Carleton University Art Gallery (CUAG) is invisible. It's also quite noisy.

While many may expect a visit to the gallery to include hushed whispers and silent observations of displays, David Rokeby’s Very Nervous System has turned the tables, with the exhibit itself observing its visitors.

The display — or more appropriately the lack thereof — consists of a single motion-sensitive video camera attached to the ceiling pointing downward, and two speakers mounted on opposite walls. A spotlight shines down on the very centre of the wood panelled floor, daring visitors to approach the invisible project.

Stepping into the camera’s line of sight, the sound of jingling metal starts to emanate from the speakers, the camera’s motion sensors converting movement into pre-recorded sounds.

Diana Nemiroff, director of CUAG is the gallery director, called Very Nervous System, “a fundamentally playful work of art. You could almost call it a sculpture of sound.”

“It works best with one person,” she explained, though there is no restriction on the number of people who can play with the piece at a time.

“The camera takes 30 snapshots a second,” Rokeby said. “A computer then looks at the differences in the photos to find movement and play the right sound. Usually a change in the pictures indicates movement, though turning on and off the lights works too.”

Rokeby's career has produced several acclaimed interactive art pieces, and he has received various accolades including the Governor General award in Visual and Media Arts in 2002. His work has been displayed around the world, including at Toronto's Luminato festival.

When Rokeby first started his career as an artist, he said he did not have an interest in using technology. “I wanted there to be room for the audience to interact,” he said, but elaborated that he found technology allowed this type of interaction. “I was experimenting with the potential of this kind of system, and how people using it would relate to their bodies and the space around them.”

Rokeby began to implement technology in his work in 1982, and worked on Very Nervous System from 1986 to 2004. Over this time there were many changes to the project.

“The most predictable change has been in the power of technology,” he said. “The early camera worked quite well, even though the resolution was quite low.” He added that the earlier system required bigger movements to register change.

The sounds that Very Nervous System produces have changed as well. “There were phases where it sounded very musical.”

The current piece uses over 80 different sounds. While most of them are of Rokeby dropping nails and moving wood in the backroom of a gallery in Winnipeg, there are also a few out of place noises, like a flock of birds in Venice and a streetcar in Toronto. “I needed a few sounds to contrast,” Rokeby explained.

Rokeby said movement in different areas triggers a feedback loop of these recordings. “I think it's appealing because the end result is always quite different,” he said.

When the earliest version of the piece came out in 1984, Rokeby said dancers and musicians were very interested in using the technology in their work. David Earle, choreographer of dance company Dancetheatre, will also use Very Nervous System for a performance in January.

Very Nervous System’s very interesting name came about through the exhibit’s resemblance to the human nervous system, Rokeby said.

“The way I was building the system,” he explained, “there were a lot of wires used, and at some point I found that the word 'nervous' can be used to mean 'lots of fibres.' I saw the wires as fibres, and so it literally was becoming a very nervous system.”

He added that the installation’s system processes what it perceives in a manner a lot like thinking, resembling how the human nervous system works.

The software used to convert movement into noise, which Rokeby created, has found uses outside of the art world.

“It's been used to enable people with various disabilities, helping some people to write emails and others to speak,” Rokeby said. “There was also a group of quadriplegics and paraplegics who were able to perform music with it. There is a difference between art and science, but there have been some very positive results.”

Very Nervous System will be on display at the Carleton University Art Gallery until Jan. 30, with a visit from the artist planned for January.