Projection of three-dimensional light fields for neurophotonics

Innovations in the physical sciences often give rise to breakthroughs in biomedical research. Such technological advances have been instrumental in providing tools to understand the brain, its circuitry and its ability to process information, which remains one of the grand challenges in science. The field of neurophotonics bridges physics and biomedical research, particularly on the creative use of optical technologies such as laser microscopy, photochemistry and optogenetics to probe brain function. Neurobiologists now rely heavily on neurophotonics, giving them the necessary tools to analyse the dynamics and principles of neural circuitry, especially on techniques to detect activity in large numbers of neurons, and to selectively excite sub-sets of neurons.

We encourage students, who are interested in multi-disciplinary collaborative work, to take part on our work on neurophotonics. We have custom-built a novel two-photon microscope, which is designed with a holographic laser projector. The system relies on photostimulation or light induced generation of neuronal signals to study how neurons process and integrate information. Using a computer-generated hologram, we dynamically generate the required 3D optical field pattern to generate neuronal signals at multiple sites along the dendritic tree of a neuron (see figure). This technique can be used to emulate the many synaptic signals neurons receive from neighbouring neurons. How a neuron processes these signals, ultimately leading to an action potential, are issues to be tackled in this study. Creative use of physics and optical techniques to solve particular issues in neuroscience can be rewarding for students with physics and engineering background.

During this project, the student will develop skills and learn:

  • Principle of two-photon absorption and femtosecond pulsed lasers
  • Three-dimensional laser microscopy
  • Computer generated hologram, optical design and system integration
  • Laser interaction with biological tissues
  • Photochemical reaction involved in photolysis
  • Basic understanding of neuronal function

Required background

Basic knowledge of lasers, optics and microscopy, basic understanding of cells/neurons 

Project suitability

This research project can be tailored to suit students of the following type(s): PhB, Honours, PhD/Masters, Summer Scholars