Longtime Backyard Brains fans may recognize Pablo Guerra in the majority of our human interface videos. When not acting for Backyard Brains, Pablo Works as Electronic Music Artist, specifically, modifying electronic music instruments in a discipline called “Circuit Bending.”
Circuit bending or also called “toy hacking” is the art of corrupting a musical toy from your childhood by opening it up and connecting a “jumper” wire to any two circuit locations until you find when the toy emits a strange sound. Finding new sounds is like a treasure hunt, and it doesn’t need any prior experience with electronics: you make different paths with the wire until you find one that changes the music. Once you find a path that makes a weird noise, you can connect it to a potentiometer allowing modulation of the noise effect.
While Previous Art Projects have existed that convert EEG to Music (and Backyard Brains has this feature as well), Pablo was interested in making a direct interface between his musical instruments using the strength of the EEG alpha wave power to control a100 kilohm digital potentiometer.
See the video of our first working prototype in action!
Thanks especially goes to BYB Developer Stanislav Mircic for developing the serial interface code that enables communication between our Heart and Brain SpikerShield, Spike Recorder, and the MCP41100 digital potentiometer
When Pablo Closes his eyes, alpha power increases, which causes the digital potentiometer to drop from95 kilohms to 70 kilohms. This then modulates a sound generation circuit in Pablo’s Musical Instrument
If you would like to build this, you must
Remove LEDs 3,4, and 6 from the Heart and Brain SpikerShield (two yellow LEDs, and last red LED). This is because we are using those pins now to talk to the Digital Potentiometer.
Upload this new code to your Arduino that allows the SpikeRecorder software to talk to the Digital Potential
Neuroscience is making its way across the globe! Recently, The Harvard South Asia Institute selected 25 young students of technology to participate in a two-week long workshop, introducing them to the excitement and interdisciplinary nature of neuroscience and engineering in Bangalore, India. Course managers included our longtime Harvard colleagues and scientists Venkatesh Murthy and Laura Magnotti , and during two weeks the students learned about brain function from ion channels on up to cognitive networks. As one part of the hands-on component of the workshop, the students did experiments using our gear! They used the Neuron SpikerBox kits to record action potentials from cricket and grasshopper legs (which the students caught themselves on campus). They also experimented with humans, recording EMG during arm wrestling contests, using the Muscle SpikerBox.
The Harvard South Asia Institute workshop seeks to introduce Indian students to the excitement of brain science, and this is the second version of the workshop; We are happy that the NeuroRevolution is expanding and creating a wider community all over the world. The workshop had graduate and undergraduate students, who usually do not sit for classes together, learning and helping do experiments on the electrical activity of neurons. For many, it was the first time doing electrophysiology!
Read the full article that was featured in The Times of India here to find out more about this workshop. Many more shall come!
In the project instructions, I’ve briefly talked about the BYB SpikeRecorder app that I’ve been using on an iPad to add to my grasshopper vision project the flavor of a low-cost-and-DIY-albeit-of-great-quality tool. Here, I’ll talk about it in a bit more details to give the spotlight to one of the main components of my project.
Firstly, the purpose of the original SpikeRecorder version that BYB has published is to record data directly to your PC (or tablets & smartphones) while you can observe the recording in real time. There’s also the functionality of saving the recording to be played back anytime. And if you’re familiar with the classic model of an action potential (aka spikes!), the SpikeRecorder also allows a threshold view, where you can set your threshold and get a snapshot of your spikes.
This is a classic “spike” event when the electrochemical properties of a neuron is at work. These spikes are essentially changes in voltage due to the chemical and electrical difference inside and outside of a neuron’s membrane. Movements of sodium and potassium across the membrane via channels and the way their charges get distributed — these are the main components of a spike.
Art by Backyard Brains
If you’re interested in checking out this app and perhaps get some spikes, the app is available for android and ios. And of course, the code is on github for the open source spirit!
One of my mentors, Stanislav Mircic, is the computer science god of BYB. He graciously added the “Grasshopper experiment” functionality to the app. The app now can provide both the visual stimuli (simulated balls thrown at grasshopper’s eye) and recording/analysis of the DCMD neuron activity.