Table 4.

Review of quantitative EEG analyses in fragile X syndrome.^a

Authors	Comparison group (n)	Method	Results
Van der Molen et al 73	FXS (8 M) HCb (12 M)	Resting state • EEG power	Increased theta Decreased upper alpha
Van der Molen et al 74	FXS (8 M) HCb (12 M)	Resting state • EEG power • Connectivity	Reduced alpha and beta connectivity Increased theta connectivity Increased path length in theta bands
Wang et al 75	FXS (15 M, 6 F) HCb (15 M, 6 F)	Resting state • EEG power • Connectivity • Cross-frequency amplitude coupling	Increased gamma Increased theta-gamma coupling Decreased alpha-gamma coupling
Proteau-Lemieux et al 76	FXS (16 M, 10 F) HC (40 M, 37 F)	Resting state • EEG power • Alpha peak frequency • Multiscale entropy (MSE)	Increased gamma Decreased alpha Decreased alpha peak frequency No difference in theta/beta ratio Decreased signal complexity using MSE
Smith et al 78	FXS (28 M, 23 F) HCb (29 M, 19 F)	Resting state • EEG power • Alpha peak frequency	Increased theta (M/F) Increased low alpha (F) Decreased beta (F) Decreased gamma (F) Decreased epsilon (F)
Wilkinson et al 77	FXS (11 M) HCb (12 M) Cognitive-Matched HC (12 M)	Resting state • EEG power	Increased gamma

Abbreviations: F, female; FXS, fragile X syndrome; HC, healthy control; M, male.

^a Studies show patterns of increased spectral power in the gamma frequency band, reduced power in the alpha frequency band, and abnormalities in network connectivity.

^bAge-matched.