Category: Neural signal processing

• Tips on using crcns datasets

  I’ve mentioned before that the CRCNS web site has a number of neural datasets available for download. To save you some time, here’s some tips to get you up and running for specific datasets. V2-1 data Jack Gallant’s V2 dataset is really interesting; I think it’s fair to say that we know very little about…

  March 29, 2014

• More neural datasets from CRCNS

  From its humble beginnings about 5 years ago, the CRCNS data sharing website has grown into a very useful resource for modelers looking to test out their theories and algorithms on neural datasets. Vision-wise, the dataset includes: eye tracking data fMRI with natural images mouse LGN cat, primate primary visual cortex with natural images, gratings…

  January 10, 2014

• Spikes trigger LFP waves: the rebuttal

  Nauhaus, Busse, Carandini and Dario Ringach published an influential paper in 2009 with pretty convincing evidence that spikes trigger traveling waves of activity visible in LFPs; that these waves travel laterally; and because the dynamics of these waves change during stimulation compared to spontaneous activity, that stimulation modulates functional connectivity. This could imply that a…

  March 3, 2012

• Setting up a cluster for the analysis of neural array data

  As I’ve mentioned before, we’ve been recording from a Utah array for more than a year now. We use a custom Plexon MAP system that allows for the recording of wideband data at 10 kHz over 96 channels. This custom configuration was requested so that we can get spike-free LFPs by preprocessing wideband data with…

  January 17, 2012

• Denoising and spike detection in a Utah array

  Our V4 Utah array died last week… and then it worked again this week. It’s pretty amazing that it’s still up and running after about 18 months. It’s gettting noisier, however, and increasingly what’s being recorded is mostly multi-unit activity (MUA). To have any chance of detecting single units, it’s therefore quite important to denoise…

  December 16, 2011

• Spike identification through Gibbs sampling #2

  Last time, I demonstrated how to use Gibbs sampling to obtain an estimate of the probability of spikes at different time points given a wideband signal. Unfortunately the method I proposed suffered from long correlation times. In this post I expand upon the previous method to obtain a practical method for identifying spikes. Making it…

  November 1, 2011