New optical recording technique can see millisecond nerve impulses
February 17, 2004 | Source: KurzweilAI
High-resolution images of millisecond-by-millisecond signaling through nerve cells is now possible by combining the bright laser light of multiphoton microscopy with specially developed dyes and a phenomenon called second-harmonic generation, say biophysicists at Cornell University and Université de Rennes, France.
This technique allows for looking at membrane potential in nerve-cell signaling with high resolution deep in intact tissue. And by “stacking” multiple images at various depths of focus, the system produces three-dimensional images or movies.
Second-harmonic generation microscopy image of a sea slug (Aplysia) neuron
The first demonstration of the new technique, reported as the cover story in the Jan. 28, 2004, issue of The Journal of Neuroscience, was in neurons of the sea slug, Aplysia. But the Cornell researchers anticipate that eventually the technique will be used in brain tissues of higher animals and could help decipher the wiring of the brain and possibly explain consequences of degenerative brain diseases such as Alzheimer’s.