Neural data-analysis Workshop Ben-Gurion University of the Negev Dept. of Brain and Cognitive Sciences Neural data-analysis Workshop

Structure array http://www.mathworks.com/help/matlab/matlab_prog/ways-to-organize-data-in-structure-arrays.html Example: student(1).FirstName = 'Adam'; student(1).LastName = 'First'; student(1).Gender = 'm'; student(2).FirstName = 'Eve'; student(2).LastName = 'First'; student(2).Gender = 'f';

Moving Gratings A common stimulus in visual experiments is a sine-wave grating. The grating can come at different orientations. Moving gratings proved to be very effective in eliciting responses of neurons in the primary visual cortex (V1).

Micro-Electrode Array (MEA) Micro-electrode arrays (MEAs) record extracellular activity and are used for recording many neurons simultaneously. In the following exercise, we will analyze spiking activity recorded using MEA from neurons in V1.

Raster plot When performing an experiment that consists of multiple repetitions of cell’s activity recording with the same given stimulus – it is a common practice to present the entire experiment as a raster plot. A raster plot is a collection of dots (each representing a single spike) plotted on the same figure. The X coordinate of each dot represents the time of the spike and the Y coordinate represents the repetition index.

psth Once the raster plot was plotted, a following common practice is to plot the PSTH of the same experiment. PSTH = Peri-Stimulus Time Histogram “[…] These histograms are used to visualize the rate and timing of neuronal spike discharges in relation to an external stimulus or event.” (http://en.wikipedia.org/wiki/Peristimulus_time_histogram) The rate is calculated by averaging the spike count in each time bin. The calculated rate for each time bin is the average spike count (over the repetitions) divided by the duration of the time bin: (# of spikes)/(# of repetitions x bin duration)

Example of division into bins