{348} revision 4 modified: 01-06-2012 03:12 gmt |
It appears that operant/feedback training of one neuron (channel 29, in SMA region) works fine (not great, but fine). In the experiment performed prior to visiting Seattle, on April 10 2007, I was not convinced that the neuron was controlling anything. Now, it is apparent that the monkey has some clue as to what he is doing. Today I made a simple change: I made the filtering function sum (all spikes) 1/12 * x*(x-1)^2, where x = time - time_of_spike. In comparison to a butterworth filter, this has no rebound oscillation & makes the estimation of firing rate much more transparent. It averages over approximately 500ms ~= lowcut of 1.5hz? I see no reason to change this filtering function much, as it works fine. Spikes were binned at 100hz as input to this function, but that should be equivalent to binning at 1khz etc. Next time, i want to do 2d, where channel 62 controls the Y-axis. really should try to determine the approximate tunings of these cells. I'm somewhat concerned as this channel seems to have a much lower mean firing rate than channel 29. According to the literature, PTNs have high firing rates and strong tuning... for reference, here is the channel used for the one-neuron BMI, recorded April 10. It has not changed much in the last 7 days. |