Does striatal Dopamine D2/D3 Receptor Availability be Associated with Executive Function in Healthy Controls but Not Methamphetamine Users?
These results suggest that cognitive flexibility, as measured by perseverative errors on the Wisconsin Card Sorting Test, is not determined by signaling through striatal D2/D3 receptors in healthy controls, and that in stimulant abusers, who have lower D2/D3 receptor availability, compensation can effectively maintain other executive functions, which are associated with D2/D3 receptor signaling in controls.
The study shows that about two thirds of children with innocent heart murmur reflect a left ventricular FT. Furthermore, FT is far more common in subjects with innocent cardiac murmur than in normal subjects. The relationship between FT and murmur thus appears very likely, although not definitely proven.