Video: Using your brain and visual stimuli to play music

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This biotronic art installation creates a unique musical experience based on thoughts and emotion.

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What if moving your eyes from left-to-right or up-and-down could trigger lights, play music and control other devices? That’s what digital artist Fèlix Vinyals has set out to accomplish with his latest project entitled Torval. Well sort of, at least. In collaboration with EEG and BCI researcher Oscar Portolés, the Maker has designed a hybrid brain computer machine interface (BCMI) installation that allows him to create music and control the lighting while on stage, all through the reading of the electric potential of his brain and visual stimuli.

The project combines two independent BCI systems. The first makes use of the steady state visual evoked potential (SSVEP) technique to enable the musician to switch on/off a set of music tracks from a MIDI sample. Meanwhile, the other determines the musician’s index of relaxation that is read through the alpha rhythm to alter the illumination of the installation. The communication between the BCMI, the MIDI sampler and the set of floodlights via DMX protocol is done with an Atmel based Arduino.

Beyond that, Torval is comprised of six main modules: the visual stimuli tool, the EEG signal acquisition unit, the signal processing algorithms for both BCI systems, the output control box (Bebop), the music sampler, and the illumination system.

“On one hand, the visual stimuli tool elicits a SSVEP in the user visual cortex when he gazes at one of the six flickering stimuli. Then, the signal-processing algorithm searches the EEG data in real time for a SSVEP. When a SSVEP is found at a frequency coincident with one of the flickering stimulus units, the outputs control box will send a MIDI command to switch on or off the musical loop associated with the particular flickering stimulus unit,” Vinyals explains.

“On the other hand, a signal-processing algorithm constantly monitors the level of relaxation of the artist – the power within the alpha rhythm of the occipital cortex. Continuously and smoothly, Bebop modifies the illumination of the stage through DMX protocol in correlation with the relaxation of the user; a shade from the color spectrum that ranges from red to blue is projected onto the stage. Therefore, the user can actively control the color of the stage. Yet, as he fully engages in the performance, he loses his ability to self-control his level of relaxation and mental load; turning the stage illumination into a genuine portrait of both physiological states.”

What’s unique about this project is that is relies only upon imagination and emotion, enabling a wearer to create a unique, irreproducible musical experience. As the video eludes to, there are eyes that speak and there are other eyes that can perform… Trust us, you’ll want to see this!