Two of the performers were given a task to watch a screen in front of them, with flashing rows and columns of letters, and told to look for a particular letter.

When expectation is fulfilled, 300 thousandths of a second later, a signal known as the P300 appears in the EEG.

A similar strategy has been employed by Mick Grierson at Goldsmiths, University of London to generate individual notes.

In the Multimodal Brain Orchestra, the P300 signal is registered – with a dot demarcating it on the EEG trace projected to the audience, so that they can see the effect of the performer’s thought – in turn launching a sound or recorded instrument. […]

Adjacent to the EEG-capped players, the “emotional conductor” sits comfortably, wearing a pair of virtual reality glasses.

She is being shown images from a series created by artist Behdad Rezazadeh while her heart rate and skin conductance are being measured. Her heart rate is plotted along with the EEG traces.

As her mood changes, so does the visual experience – Rezazadeh’s images are blurred and changed in line with the changing biological measures of the conductor.

BBC: World premiere of brain orchestra

(Thanks Wade)

See also Ikipr’s EEG workshop at Esozone: the Other Tomorrow.