I assume that you already check the file 'Jan_14_1131.csv' and make sure there is a parameter 'keyResponse2corr' in the csv file.
It seems that the error message you got is directly generated from the catch block, so you may have a bug in the try block. The bug is resulted from the mismatch of number of input argument for function 'fileparts', I suggest you try to replace
[~, varname] = fileparts(filename);
[~, varname,~] = fileparts(filename);
and see if this works for you.