“…Structural brain abnormalities among frequent methamphetamine users as compared to healthy controls have also been observed, including, but not limited to, reduced white-matter integrity and/or organization associated with depression severity and positive psychiatric symptoms (Tobias et al, 2010), reduced gray matter in the cingulate, limbic, and paralimbic cortices (Thompson et al, 2004), reduced hippocampal volumes associated with poorer memory performance (Thompson, et al, 2004), altered shape of the corpus callosum (Oh et al, 2005), and increased volumes of the putamen and globus pallidus (interpreted as a compensatory effect; Chang et al, 2005). As noted by Berman and colleagues (2008), lower cortical gray matter density or volume is the most consistently reported structural abnormality in amphetamine users, and studies assessing striatal gray matter report larger volumes in amphetamine abusers when compared to healthy controls, although the latter may reflect a compensatory response to initial neurotoxicity (S. Berman, et al, 2008).…”