  We study the nature of the hidden charm pentaquarks, i.e. the $P_c(4312)$,
$P_c(4440)$ and $P_c(4457)$, with a neural network approach in pionless
effective field theory. In this framework, the normal $\chi^2$ fitting approach
cannot distinguish the quantum numbers of the $P_c(4440)$ and $P_c(4457)$. In
contrast to that, the neural network-based approach can discriminate them. In
addition, we also illustrate the role of each experimental data bin of the
invariant $J/\psi p$ mass distribution on the underlying physics in both neural
network and fitting methods. Their similarities and differences demonstrate
that neural network methods can use data information more effectively and
directly. This study provides more insights about how the neural network-based
approach predicts the nature of exotic states from the mass spectrum.
