.
\citep{He2022} tested the contribution of brain γ-aminobutyric acid (GABA) and glutamate levels of the right primary sensorimotor cortex (SM1), supplementary motor area (SMA), and insular cortex (insula) to tic and urge severity in children with GTS. As a result, they have demonstrated involvement of GABAergic neurotransmission within the SMA in the experience of PU in children with GTS.