Cortically Magnified

I created this figure to illustrate the retinotopic map of the primary visual cortex of the marmoset. The eccentricity contours are plotted in red, and polar angles are in blue. It’s very easy to create it in 3D so that you can rotate it around and see it from different angles. This is how you do it: Download ParaView, the open source 3D data visualization package.

This figure illustrates the direction tuning curves of two motion sensitive neurons recorded in the primary visual cortex. The two neurons were so close to each other that their activities could be picked up by the same electrode. Interestingly they preferred polar opposite directions.

Demonstrations: The reconstruction of Mona Lisa video. A blog post I wrote about the Fourier transform trick. Youtube video: Nobel laureates David Hubel and Torsten Wiesel recording neurons in cat’s V1. Suggested readings: Fourier transform An introduction to two-dimensional fast Fourier transforms and their applications by Rzeszotarski et al. (1983). Fourier transforms and frequency-domain processing (Chapter 5 of Fundamentals of Digital Image Processing: A Practical Approach with Examples in Matlab by Solomon & Breckon, 2011) Suggested readings: programming See this web page from UCSB.

Central disorders of vision in humans by Girkin & Miller (2001): a review of what happens if different parts of the visual cortex are damaged. “Superimposed hemifields in primary visual cortex of achiasmic individuals” by Sinha & Meng (2012, Neuron 75): Newton vs. Descartes on the organization of the optic chiasm. Youtube video demonstrating how Hubel & Wiesel mapped V1 receptive fields.

Animal Eyes by Land & Nilsson is a very nice little book about the fascinating variety of eye structures found in nature. Youtube video about the “connectome” of the retina