Glutamate-Glutamine Cycling (VCYC) During Cocaine Abstinence Using 1H-MRS

Upon completion of baseline (abstinence) 1H-MRS scanning, CU and HC subjects will participate in two additional 1H-MRS scans, including after 2 weeks of placebo and 2 weeks of NAC administration (3600 mg/day) given in double-blind, randomized, counterbalanced order.

All subjects will undergo \[18F\]FDG PET to establish previously demonstrated reductions in glucose utilization in PFC and assess VS/nucleus accumbent metabolism at baseline.

All subjects will undergo three magnetic resonance spectroscopy (1H-MRS) scans at 7T, including before and after two-weeks of placebo and NAC administration.

All subjects will undergo \[11C\]APP311 PET imaging to investigate whether there are differences in synaptic integrity / neuronal plasticity in the brains of individuals abstinent from cocaine compared to healthy controls at baseline.