Flor-Henry, 2000). Moreover, it has been suggested that smell identification deficits are relatively specific to schizophrenia (Hurwitz et al., 1988) and its negative symptoms (Malaspina & Coleman, 2003), including in young people with psychotic disorders (Corcoran et al., 2005), which can not be accounted for by cognitive impairment (Seidman et al., 1991, 1997), socioeconomic status, smoking or medication (Coleman et al., 2002; Malaspina & Coleman, 2003; Turetsky et al., 2003b). Interestingly, unaffected relatives of schizophrenia patients also showed poorer smell identification (Kopala et al., 2001; Turetsky et al., 2008) and elevated odor thresholds, which were intermediate between patients and controls (Roalf et al., 2006). Although these data suggest a genetic component, there has been some controversy about the extent to which olfactory identification deficits may constitute a meaningful, broader vulnerability marker of schizophrenia pathology (Cohen et al., 2012a,b; Turetsky et al., 2012).
