Skip to content

Mehta et al. 2019 JNeurosci Ventromedial prefrontal cortex tracks multiple environmental variables during search

Notifications You must be signed in to change notification settings

cindyhfls/Mehta-2019-JNeurosci-SearchTask

Folders and files

NameName
Last commit message
Last commit date

Latest commit

 

History

21 Commits
 
 
 
 
 
 
 
 
 
 
 
 

Repository files navigation

SearchTask

This is the anaysis code related to Figure 10 in "Ventromedial prefrontal cortex tracks multiple environmental variables during search" by Priyanka S Mehta, Jiaxin Cindy Tu, Giuliana A LoConte, Meghan C Pesce, Benjamin Y Hayden at Journal of Neuroscience (2019)

1. Data Description (the task is described in details in the paper

There were 4/7 diamonds on the screen for each trial. The offer value can be seen by staring at the diamonds, max__offer * ratio where ratio = 0-1. Staring any offer for 200ms = choice. Total Neuron Number = 122 ScreenSize was larger for Neuron 12-70 PSTHs: Centered around the offers the monkey have checked, 10s before, and 10s after. The number of offers checked is the length of vars.masksOpened. This determines the number of psths per trial. We want the period from stimulus onset to choice, but I will discuss this with Michael again.

diamond fixation = 400 ms bar fixation (completed) = 300 ms bar rejection < 300 ms

2. The main function was main_anal_search_task.m

It calls fitting of parameters for some # distribution function #. Fitting was done by fminsearchbnd.m (a function from the Internet which was based on MATLAB fminsearch function). What it does is fitting paramters by gradient descent, to maximize the loglikelihood.

3. The log likelihood of the model was calculated with log_likelihood.m

This can be changed to include multiple variables (with different distributions). And then calculate the joint probability e.g. (log_likelihood_x + log_likelihood_y + ...). Since the log likelihoods are additive, find the best-fit distribution for each variable if you want to fit a joint probabilty.

4. Distribution Functions: e.g. vonmises.m/linear.m

% remember to add in the constant term for each distribution Customized Likelihood Functions, which takes several parameters and ouput the probability given an independent variable x. if x is x-coord/y-coord/velocity use Linear/Gaussian/(Mixed-Gaussian/Cubic spline/Exponential/Polynomial) elseif x is angle (in deg or rad) use the Von mises function (which assumes 0 and 360 is the same). end

5. The models are compared with Uniform Distribution using AIC, BIC criteria.

https://www.mathworks.com/help/econ/aicbic.html

About

Mehta et al. 2019 JNeurosci Ventromedial prefrontal cortex tracks multiple environmental variables during search

Resources

Stars

Watchers

Forks

Releases

No releases published

Packages

No packages published