Using Workbench Command

STATISTICS ALONG CIFTI COLUMNS
   wb_command -cifti-stats
      <cifti-in> - the input cifti

      [-reduce] - use a reduction operation
         <operation> - the reduction operation

      [-percentile] - give the value at a percentile
         <percent> - the percentile to find, must be between 0 and 100

      [-column] - only display output for one column
         <column> - the column index (starting from 1)

      [-roi] - only consider data inside an roi
         <roi-cifti> - the roi, as a cifti file

         [-match-maps] - each column of input uses the corresponding column
            from the roi file

      [-show-map-name] - print column index and name before each output

      For each column of the input, a line of text is printed, resulting from
      the specified reduction or percentile operation.  If -roi is specified
      without -match-maps, then each line will contain as many numbers as there
      are maps in the ROI file, separated by tab characters.  Use -column to
      only give output for a single data column.  Exactly one of -reduce or
      -percentile must be specified.

      The argument to the -reduce option must be one of the following:

      MAX: the maximum value
      MIN: the minimum value
      INDEXMAX: the 1-based index of the maximum value
      INDEXMIN: the 1-based index of the minimum value
      SUM: add all values
      PRODUCT: multiply all values
      MEAN: the mean of the data
      STDEV: the standard deviation (N denominator)
      SAMPSTDEV: the sample standard deviation (N-1 denominator)
      VARIANCE: the variance of the data
      TSNR: mean divided by sample standard deviation (N-1 denominator)
      COV: sample standard deviation (N-1 denominator) divided by mean
      L2NORM: square root of sum of squares
      MEDIAN: the median of the data
      MODE: the mode of the data
      COUNT_NONZERO: the number of nonzero elements in the data