A new higher order Schrödinger equation characterized by a position-dependent mass is introduced based on long-range spatial kernel effects and von Roos arguments. The extended Schrödinger equation depends on the sign of the moments
M
k
,
k
=
0
,
1
,
2
,
…
and a stabilized quantum dynamic is realized for
M
2
>
0
and
M
4
>
0
. We have discussed its implications in several quantum mechanical systems where more than a few were raised, mainly the emergence of the quantum Pais-Uhlenbeck and the relativistic quantum harmonic oscillators besides the complex periodic potential characterized by a
PT
symmetry.