We determine chiral loop corrections to the B meson decay amplitudes to
positive and negative parity charmed mesons within a framework which combines
heavy quark and chiral symmetries. Then we investigate the impact of the
lowest-lying positive parity heavy mesons on the determination of the
Isgur-Wise functions. The corrections due to these states are competitive with
the contributions arising from K and eta meson loops. Since lattice studies
rely on the chiral behavior of the amplitudes we discuss the chiral limit of
our results. We find that the determination of the slope at zero recoil of the
Isgur-Wise function xi for the B transition to negative parity charm mesons is
moderately affected by the inclusion of new states, while the slope of
tau_{1/2} is affected significantly more.Comment: 10 pages, 4 figure