“…In [21,22,36,38,39,62], methods were developed to derive excitation features from the speech signal. In [15,16,18,27,41,41,42,44], the authors analyzed excitation features [instantaneous fundamental frequency (F 0 ), strength of excitation (SoE), energy of excitation (EoE) and loudness (η)], which are extracted at the sub-segmental level of speech, for four emotions (anger, happiness, sadness and neutral state). Motivated by the good results achieved in [15,16,18,27,41,42,44], where it was shown that excitation features capture significant information about emotions, we make a systematic investigation in the analysis of features for two databases (including cases where lexical content is both same and different) and develop an emotion recognition system using neutral speech features as reference.…”