What do imaging studies show about the effect of cocaine on the brain?
a. D2 receptor availability is increased in crack users compared to controls
b. Cocaine use is related to DA availability that varies with brain region
c. There is some evidence for regions of hyperfusion in the frontal lobe in cocaine users
d. While cocaine abusers show decreased gray matter in certain areas, there appears to be no related deficit in cognitive functioning.
e. Glucose utilization is decreased in the parietal lobe in chronic cocaine users