  The higher twist corrections $h^N(x)/Q^2$ to the spin dependent proton and
neutron $g_1$ structure functions are extracted from the world data on
$g_1(x,Q^2)$ in a model independent way and found to be non-negligible. Their
role in determining the polarized parton densities in the nucleon is discussed.
It is also considered how the results are influenced by the recent JLab and
HERMES/d inclusive DIS data.
