# 10 Dream
Brainwaves from sleeping rats and humans transferred to two amplified piano strings.

Figure 1: Rendering of the installation

Video of the first prototype

The phase of sleep is one of the most intimate and silent recurring moments of life. #10 Dream is an audio-visual installation, that is capturing this very intimate moment, making it tangible to the visitor by actuating two long piano strings with pre-recorded EEG data.

One of the strings is actuated by human brainwaves, the other one by the mind of a rat. The listener is experiencing the subconscious activity of both minds joined together. But even though this seems to be a very unlike couple, both sleeping patterns sound surprisingly similar. During sleep, the brain’s activity is very dynamic. It goes through multiple episodes of changes, constantly switching between non-REM and REM episodes. Because the brain’s activity is very similar to the waking state it is also called paradoxical sleep. It is the state when dreaming occurs. Even though these episodes show very similar activity patterns among different species, duration and repetitions vary between species, but also between ages.

These always changing activity patterns construct two constantly changing sonic environments that interfere with each other through the resonance of the strings. The two minds, that are very alien to each other, disperse into one interlaced dream-like soundscape. Simultaneously the brainwaves are visualized on an oscilloscope standing next to the installation, to give the observer an idea on how these sounds are created.

By relating the humans sleep to the sleep of laboratory rats, the human takes the role of an subject of research, which is also emphasized in the choice of materials: two aluminum profiles and an oscilloscope give the impression of a laboratory setup. Thus the human gets dehumanized. The sounds that are created by the two piano strings are deep and drony. They are similarly disturbing, but also calming. It seems like the consciousness of the listener gets synchronized with these of the two lab subjects. This intimate moment of sleep creates a soundscape that produces a fundamentally human reaction of empathy within the listener.

Figure 2: Second Prototype

The installation works by actuating two piano strings with prerecorded brainwaves (EEG Signals) of sleeping humans and rats.

The the EEG Data was found in public Databases in the internet or extracted from medical publications. The Signals are extracted from these Data Sets, upsampled and and converted to audio signals. The raspberry pi controls to lifting-electromagnets that transfer the eeg signals on two piano strings. The signal is visualized by an oscilloscope. Guitar pickups are used to sense the movement of the strings, feeding the signal back into an active loudspeaker to make them audible.

Figure 2: Second Prototype

Since each of the strings has its own root note, the string will only resonate strongly to the root’s frequency or any of it’s harmonic frequencies, which creates an harmonic drone-like soundscape. The brain’s activity during sleep is very dynamic and changing, so the soundscapes are constantly altered creating different sound patterns for each string. By tuning both strings to slightly different root frequencies and letting them interfere which each other, the installations creates a constantly changing drone out of the brainwaves.

The oscilloscope visualizes the EEG brainwaves that are actuating the string, giving the observer a visual feedback and an idea of how these soundscapes are generated.