  In this work, we treat $\Lambda_c(2910)^+$ and $\Lambda_c(2940)^+$ as the
conventional $udc$ cores dressed with the $D^*N$ channel. We provide a possible
interpretation to both $\Lambda_c(2910)^+$ and $\Lambda_c(2940)^+$ within the
same framework. In the study, we consider not only the effects between the
conventional triquark core and the $D^*N$ channel but also the $D^*N$-$D^*N$
interactions. The mass of $\Lambda_c$ state with $J^P=1/2^-$ is larger than
that with $J^P=3/2^-$ in this unquenched picture, which is very different from
the prediction of the conventional quenched quark model. Based on the mass
spectrum, the spin-parity of $\Lambda_c(2940)^+$ is more likely to be $1/2^-$
while $\Lambda_c(2910)^+$ prefers $3/2^-$. We look forward to the future
experiments can test our results with more precise experimental data.
