Table 7.

Summary of EEG-based BCI emotion recognition studies.

References	No. of subjects	Stimulation	Emotion types	EEG features	Classification algorithm	Performance evaluation
Wei et al. (2017)	12	Pictures	Positive and negative	PSD, SP, CSP	LDA	Average accuracy: 86.83%
Wang X.-W. et al. (2014)	6	Movie clips	Positive and negative	PSD	LDA	CA: 91.77%
Liu Y. et al. (2017)	30	Movie clips	Joy, anger, fear, sadness, disgust, and neutrality	PSD	LIBSVM	Average accuracy: 89.45%
Kaur et al. (2018)	10	Video clips	Calm, angry, and happy	FD	RBF SVM	CA: 60%
Özerdem and Polat (2017)	32	Music clips	Positive and negative	DWT	MLPNN	CA: 77.14%
Pan et al. (2016)	6	Photos	Happiness and sadness	CSP	SVM	CA: 74.17%
Djamal and Lodaya (2017)	10	Music	Excited, relaxed, and sad	WT	LVQ	CA: 87%
Murugappan (2011)	20	Video clips	Disgust, happiness, fear, surprise, and neutral	Entropy	K-NN	CA: 82.87%