FC between brain areas can be damaged by substance abuse (Sutherland et al., 2015). Especially, studies have reported that alcohol may have harmful effects on FC (Kaplan et al., 1985; Winterer et al., 2003; Correas et al., 2016; Herrera-Díaz et al., 2016) because it can impair the development of myelin, which plays an important role in the speed of information transmission (Jacobus et al., 2009; Squeglia et al., 2015). White matter damage caused by improper myelination (Hommer et al., 2001; O’Neill et al., 2001) results in impaired connections between brain areas located at a distance from each other, in turn reducing the efficiency of information transmission (de Bruin et al., 2004; Thayer et al., 2013; Correas et al., 2015). Therefore, alcohol not only damages various brain areas (Laakso et al., 2000; Males, 2009) but also impairs the connections among them.
