In human studies, as in rats, gamma oscillations in the basal ganglia have been found to precede movement (Brown, 2003) and are thought to be of functional importance, as demonstrated by their recovery following levodopa treatment (Brown et al., 2001; Cassidy et al., 2002). Pathological oscillation patterns in the basal ganglia, including the striatum, are a key characteristic of Parkinson's disease. While much effort has focused on oscillations in the GP and STN where DBS is particularly effective (Brown, 2007), the role of the striatum in providing inputs to these areas is also being explored (Courtemanche et al., 2003; Goldberg et al., 2004; Levy et al., 2002; Raz et al., 2001). As the main input nucleus of the basal ganglia, the striatum is likely to be an important contributor to oscillation patterns observed in STN and GP. In ventral striatum, the effectiveness of DBS to alleviate the symptoms of OCD and major depression is starting to be explored, with some success (Aouizerate et al., 2009; Okun et al., 2007; Schlaepfer et al., 2008; Tass et al., 2003; Vassoler et al.
