Fish-brain-machine / Radiona workshop

After constructing the Fish-brain-machine PCB circuits we spent some time experimenting and describing the hallucinogenic visuals created by the stroboscopic light. The ping pong balls over the eyes diffuse the LED light, making for a more intense effect – and enabling use with eyes open. Here they describe some of the effects including seeing colours and ‘a strange experience’ of seeing with only one eye – I get this exact same feeling when using it. It is also hard to know if your eyes are open or closed. [See also Re-mapping the senses workshop ]



Radiona workshop, Zagreb

I’m doing a workshop related to my research, perceptual illusions and altering perception through experiments, Clay hand illusion and other activities based on sound and light and taste, at Radiona Zagreb, 21-22/04/2018 check out the web Re-mapping the senses workshop page and resources here…


Enki PCB

Fish-Brain-Machine circuit
The Fish-Brain-Machine circuit represents biology of an electro-genic fish known as the Black Ghost Knife Fish. These fish navigate with electrical fields generated from within their bodies. Their skin is used as a receptor to see the world around them.

The Enki project used the electrical signals from these fish to control stroboscopic flashing lights that create hallucinogenic visual patterns, that in turn affect our brain states*. Sweat sensors send a signal back to the fish, creating an interconnected loop of biofeedback between the human and fish.

This Fish-Brain-Machine circuit senses sweat levels on your fingertips to control the stroboscopic LEDs. Place this over the eyes, sit back and experience hallucinogenic visuals. The Circuit represents the Enki project in miniature and was designed in collaboration with Marc Dusseiller as part of the Enki exhibition Kapellica Gallery, Ljubljana, SloveniaLink to Enki Project 2012…
See the original Post…

Chip spec :
CMOS Quad-NAND gate

Capacitor 470nJ = 0.47 uF at 63V

2 – 8 MOhm Resistor

2 bright LED’s

Battery Clip (either 9V clip – very bright, or 2 holders for 3V coin batteries)




As part of my Enki exhibition at Kapellica Gallery in Ljubljana 2012, I developed a related perceptual illusions and brain hacks workshop with Marc Dusseiller [Hackteria], as part of the gallery’s Biotech program. We came up with the idea to make a special issue circuit for the workshop and we set to work designing a circuit the encapsulated the Enki project in miniature.


After a couple late nights, we came up with this super cool PCB design. Marc worked hard to create a fully functional efficient design, which was also aesthetically pleasing. The outline of the fish is also the ground in the circuit. This has to be the most ultra minimal brain-machine available to build. 6 components. We spent further late nights acid etching the circuits for the workshop in Marc’s home lab.


It uses ‘biofeedback’ to control the pulse frequency of the lights, low tech Galvanic skin response. Your fingertips press on the fingerprint, acting like a simple resistance meter, sensing the sweat levels to control strobe frequency [specifically 10-30htz to create hallucinations] of two ultra-bright LEDs to create the optical stimulation. The capacitor and resistor set the standby slow pulse and the range within the level necessary to cause visual hallucination. The design incorporates measurement graduations for eye spacing so you can personalise LED placement to fit your eyes.

It’s possible to use extra LEDs and several colours.  After soldering the 6 components its possible to layback and experience your own personal electronic psychedelic experience.

Fish brain interface DIY PCB
Marc Dusseler Fish brain interface DIY PCB

Strange face illusion with two-way Mirror feedback


A version of the Strange Face illusion with video feedback and face tracking through a two-way mirror

“… a quiet room dimly lit by a 25 W incandescent light. The lamp was placed on the floor behind the observer so that it was not visible either directly or in the mirror. A relatively large mirror (0.5 m60.5 m) was placed about 0.4 m in front of the observer. The luminance of the reflected face image within the mirror was about 0.2 cd mÿ2 and this level allowed detailed perception of fine face traits but attenuated colour perception…The task of the observer was to gaze at his/her reflected face within the mirror. Usually, after less than a minute, the observer began to perceive the strange-face illusion…”  Giovanni B Caputo, Perception, 2010, volume 39, pages 1007 – 1008 2010


Mechanically Augmented Reality

When I first learned about the Rubber hand illusion [RHI] I immediately began to think about ways in which the process could be automated to create an artwork, in which the experimenter’s presence was removed. This could be done using sensors and a microcontroller to articulate solenoids to tap fingers for example. That thought train was on a back burner until discovered the work of fellow MMU PGR Lin Charlston. As part of her PhD research [See her profile here ‘The Multimodal book as organism, artefact and assemblage: non-human agency in processes of growing and making’] She invented a beautifully simple, entirely mechanical device just to do exactly this.

Drawing of Lin Charlstons device ‘Meshy’

Your hand is placed inside a box, while the other hand turns a crank. On top of the box, another rubber hand is placed. This is where Lin’s experiment takes on its own twist; on top of the rubber hand is a piece of moss. Fixating on this, and turning the crank, a copper disk rotates.  A delicate metal bead curtain brushes over the moss, and over the fingers of the false hand. Simultaneously the hidden real hand receives the same treatment. If the illusion works for you, ownership begins to drift from your real hand to the fake hand. Specifically, the moss begins to feel like it is part of your own hand. [if you are not familiar with the Rubber Hand Illusion check this post]


Although Lin has not settled on a name for the device yet, I couldn’t help trying to think of what one might call such a device and came up with the term ‘Propriosope’ [or Propioscope as I noted] a device for shifting bodily ownership from a body to another body or object [see my post on Unfeaseable objects here…] One could imagine autonomous devices made based on any number of experiments related to the RHI [See my post on Illusions of Invisible, alien hands, 3 arms, and shrinking bodies ]

Experiments with cranks


This has made me reflect on the use of the crank as a convenient mechanism of ‘interaction’. For example; In the RHI synchronous tapping and stroking is essential to generate the illusion. A direct and tangible relationship between what is seen and felt.

Its difficult for the experimenter to replicate this manually, thus a system that can deliver this automatically could useful. It could also be useful in terms of ‘Augmented Virtuality’ interacting with real-world objects in virtual space.
The crank ensures the participant has their hands arm and body in a certain position. And they probably know how to operate the crank intuitively. img_1811                    

The above sketch shows an idea for an experiment: A version of Lin Charlstons device scaled up to resemble a version of body swap illusion [ Henrik Ehrsson and Olaf Blanke]. In which a VR headset was linked to a live camera feed whereby the participant can view their own body, but from a few meters behind themselves. The experimenter taps their back with a stick. In this crank operated version:

  • A person turns a crank.
  • In front of them is a box with an eyepiece into which they look.
  • As they turn the crank, an articulated human model inside the box also turns a crank in synchronisation.
  • The crank turns a ball on a post gently taps both model and participant on the back.

We could try the same arrangement as a physical model, a virtual model viewed in VR. Or linked video, in which the playback is synced exactly with the movement of the crank. How powerful would the effect be? What other Stimuli could be incorporated instead of a tapping ball.

I have experienced something similar in action through an artwork by painter Iain Nicholls and creative technologist Tom Szirtes. ‘Veil’ is a virtual reality work that references early filmmaking, fairgrounds, and the paintings of Velazquez, David Fredrick and Holbein.  The site-specific installation includes a cardboard model house sitting on a plinth and a virtual reality headset which the visitor is invited to wear.

But there is a handle to turn as well, therefore, I would say this verges on Augmented virtuality. I found it to be a powerful effect. I will be writing about this installation and others for the next post…


On the embodiment of unfeasible objects

Further to my last post detailing experiments relating embodiment of invisible and even third hands, here are some notes on my first ‘Clay hand Illusion’ experiments…

The ‘Rubber hand illusion’ shows it is possible to convince participants that a rubber hand is their own by placing it in front of them while stroking it in the same way as their hidden real hand. The use of self-made clay hands, or objects [see below] in place of the rubber hand raises several interesting possibilities for exploration, which move away from the embodiment of replica body parts, and towards the possible embodiment of modified body parts, or completely ‘unfeasible’ objects.tactile_object3.jpgThe clay allows for the gradual and immediate morphing of forms and for the participant to build a sensory connection with the object through its creation. As an artist [who has worked with clay] I feel a sense of deep connection with the objects I make, especially during making them. For example, I feel my face move and contort when I am trying to draw a face. I wonder if this is true of others? This is why for my first participants I am choosing those who work with clay.

In regard to the embodiment of ‘unfeasible’ objects, the possibility of such a thing has been loosely disproven in several studies [See ‘The Invisible Hand Illusion’]. Whereby a plank of wood and a spoon were substituted in place of the embodied hand. Therefore I am keen to explore this further. So far I have had encouraging results which build on the results from the first workshop session [See image below]. Is it easier to achieve a connection with self-made objects, rather than an irrelevant object, such as the plank of wood?
hands03In my first ‘beta’ study, I worked with a participant who is a maker and uses clay in their work. After making a good connection with their self-made clay hand, I asked if they could make a non-hand like an object, or a modification to the clay hand, for a further experiment. They immediately opted to make a roundish blob. Followed by a further iteration; a doughnut shape. They were able to make a strong feeling of connection with the blob and the Doughnut, though not as strong as to the hand, and the connection took longer to achieve. The connection was patchy, in parts, and mapped over the surface.

I found that the fingers could be mapped around the object by using a combination of synchronous tapping and swapping over the embodied finger with other digits, and the moving the already embodied finger over to a new location on the object. For example, the index finger feels fully connected to the clay object but, the ring finger does not. So I tap on the real ring finger and say I’m tapping on the index finger. They then seem to believe that this finger is now connected, when I return to the index finger – they now believe the finger next to the index finger is now newly connected to the clay. It’s not easy to explain! Mor on this later. The main part of the hand did not feel fully embodied.

It seemed like that with time, and combinations of synchronous and non-synchronous tapping, the hand could be mapped in two dimensions over the surface of the object.

I also found an interesting ‘compression’ in the perceived length of the fingers! When I tapped on the knuckle where the finger joins the hand, the participant thought this was the middle of their finger.

Working with the clay has an interesting effect of leaving traces of the tapping and stroking process so over time a textural surface is built up. When experimenting with the clay blob the participant made the following comment…

IMG_1640Unfeasible Object #1 Participant 1

 “I fully believe that’s my hand, but like there’s an obstacle, like you cant push past it…it feels like my hand is made out of this clay, but there is only so far you can push into it…it feels like a barrier”

The barrier seemed to be just under the surface of the clay. Perhaps this suggests a  surface-deep sensation of the perceived embodiment? Another interesting comment…

“Its like when I’m making something, I can feel my hand moulding something, and it feels like I’m on the opposite side of that”

The significance of this comment hit home when my supervisor picked up on the idea of ‘actions’ ie how we might hold an object, or how the object was made. Could embodiment of these objects be stronger if I considered them from the point of view of how they might be handled? This makes me think of ways in which the underside of the hand could be used in the illusion, rather than the back of the hand as is traditionally used. An upside down or inside out version of the Rubber hand Illusion? My experiment continues to evolve…