Note that this reference documentation is identical to the help that is displayed in MATLAB when you type “help ft_crossfrequencyanalysis”.

  FT_CROSSFREQUENCYANALYSIS performs cross-frequency analysis
  Use as
    crossfreq = ft_crossfrequencyanalysis(cfg, freq)
    crossfreq = ft_crossfrequencyanalysis(cfg, freqlo, freqhi)
  The input data should be organised in a structure as obtained from the
  FT_FREQANALYSIS function. The configuration should be according to
    cfg.freqlow    = scalar or vector, selection of frequencies for the low frequency data
    cfg.freqhigh   = scalar or vector, selection of frequencies for the high frequency data    = cell-array with selection of channels, see FT_CHANNELSELECTION
    cfg.method     = string, can be
                      'coh' - coherence
                      'plv' - phase locking value
                      'mvl' - mean vector length
                      'mi'  - modulation index
    cfg.keeptrials = string, can be 'yes' or 'no'
  Various metrics for cross-frequency coupling have been introduced in a number of
  scientific publications, but these do not use a sonsistent method naming scheme,
  nor implement it in exactly the same way. The particular implementation in this
  code tries to follow the most common format, generalizing where possible. If you
  want details about the algorithms, please look into the code.
  The modulation index implements
    Tort A. B. L., Komorowski R., Eichenbaum H., Kopell N. (2010). Measuring Phase-Amplitude
    Coupling Between Neuronal Oscillations of Different Frequencies. J Neurophysiol 104:
    1195?1210. doi:10.1152/jn.00106.2010