A Systematic Review on Muscle Synergies: From Building Blocks of Motor Behavior to a Neurorehabilitation Tool

Table 1

The spectrum of performance of different algorithms for synergy estimation from the EMG signal affected with Gaussian noise and signal-dependent noise performance of algorithm in the identification of the subspace and activation coefficients [94].

Performance	Gaussian variance noise (synergy estimation)	Signal-dependent noise (synergy estimation)	Identifying subspace	Activation coefficient
PCA	Low	Low	High	Intermediate
ICA	High	Intermediate	Low	Low
FA	High	Intermediate	High	High
NNMF	Intermediate	Intermediate	Intermediate	Intermediate
ICAPCA	High	High	High	High
pICA	High	High	High	High