and
suggests that BCAA administration might
be a viable way of attenuating dopaminergic overactivity in pathological states.
It is of additional interest that in this
study the control drink was a true placebo.
Our original study employed a ‘balanced’
drink containing substantial doses of tyrosine, making it possible that the difference
in effects simply reflected a contrast
between a high-tyrosine and low-tyrosine
state. For example, a recent study in volunteers suggests that a tyrosine-containing
drink can increase alertness (Grevet et alet al,
2002).