LED Zappelin': An open source LED controller for arbitrary spectrum visual stimulation and optogenetics during...

Area of Science:

• Neuroscience
• Biomedical Engineering
• Optical Imaging

Background:

• Two-photon (2P) microscopy is vital for neuroscience but struggles with integrating arbitrary light stimulation due to signal crosstalk.
• Existing methods for combining 2P imaging and light stimulation are often complex and costly.

Purpose of the Study:

• To develop a simple, low-cost electronic solution for time-interleaved light stimulation and fluorescence detection in 2P microscopy.
• To overcome the challenge of spectral crosstalk between stimulation light and fluorescence detection.

Main Methods:

• Utilized an ESP32 microcontroller and TLC5947 LED driver for precise control.
• Implemented rapid time-interleaving of stimulation and detection epochs during scanning.
• Designed a system capable of driving up to 24 LEDs with arbitrary spectra.

Main Results:

• Successfully demonstrated a functional electronic stimulator for under $100.
• Validated the system's utility in color vision experiments on zebrafish retina.
• Applied the stimulator for optogenetic circuit mapping in Drosophila.

Conclusions:

• The developed electronic stimulator offers an accessible and effective solution for advanced 2P microscopy applications.
• This technology facilitates complex experiments, including in vivo color vision studies and optogenetic circuit analysis.