Costello syndrome (CS) is due to a gain of function mutation in HRAS that is involved in LTP-like phenomena.

PAS and iTBS induce a similar enhancement in brain excitability in healthy subjects.

PAS leads to a pronounced increase in motor cortex excitability in CS, but no data about the effects of iTBS are available.

Unlike healthy subjects, PAS and iTBS induced differential effects on motor cortex excitability in CS.

HRAS differentially influences iTBS- and PAS-induced plasticity in humans.