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 reference:minimumnormestimate [2018/08/23 14:43] reference:minimumnormestimate [2018/08/23 14:43] (current) Line 1: Line 1: + =====  MINIMUMNORMESTIMATE ===== + + Note that this reference documentation is identical to the help that is displayed in MATLAB when you type "help minimumnormestimate"​. + + <​html><​pre>​ + <​font color=green>​MINIMUMNORMESTIMATE​ computes a linear estimate of the current in a + distributed source model. + + Use as + [dipout] = minimumnormestimate(dip,​ grad, headmodel, dat, ...) + + Optional input arguments should come in key-value pairs and can include + '​noisecov' ​        = Nchan x Nchan matrix with noise covariance + '​noiselambda' ​     = scalar value, regularisation parameter for the noise covariance matrix (default = 0) + '​sourcecov' ​       = Nsource x Nsource matrix with source covariance (can be empty, the default will then be identity) + '​lambda' ​          = scalar, regularisation parameter (can be empty, it will then be estimated from snr) + '​snr' ​             = scalar, signal to noise ratio + '​reducerank' ​      = reduce the leadfield rank, can be '​no'​ or a number (e.g. 2) + '​normalize' ​       = normalize the leadfield + '​normalizeparam' ​  = parameter for depth normalization (default = 0.5) + '​keepfilter' ​      = '​no'​ or '​yes',​ keep the spatial filter in the output + '​prewhiten' ​       = '​no'​ or '​yes',​ prewhiten the leadfield matrix with the noise covariance matrix C + '​scalesourcecov' ​  = '​no'​ or '​yes',​ scale the source covariance matrix R such that trace(leadfield*R*leadfield'​)/​trace(C)=1 + + Note that leadfield normalization (depth regularisation) should be done + by scaling the leadfields outside this function, e.g. in + prepare_leadfield. Note also that with precomputed leadfields the + normalization parameters will not have an effect. + + This implements + * Dale AM, Liu AK, Fischl B, Buckner RL, Belliveau JW, Lewine JD, + Halgren E (2000): Dynamic statistical parametric mapping: combining + fMRI and MEG to produce high-resolution spatiotemporal maps of + cortical activity. Neuron 26:55-67. + * Arthur K. Liu, Anders M. Dale, and John W. Belliveau ​ (2002): Monte + Carlo Simulation Studies of EEG and MEG Localization Accuracy. + Human Brain Mapping 16:47-62. + * Fa-Hsuan Lin, Thomas Witzel, Matti S. Hamalainen, Anders M. Dale, + John W. Belliveau, and Steven M. Stufflebeam (2004): Spectral + spatiotemporal imaging of cortical oscillations and interactions + in the human brain. ​ NeuroImage 23:582-595. +