Anomalous signature splitting and signature inversion for the configuration \pi h_{11/2} \otimes \nu i_{13/2} in rotational bands of odd-odd nuclei have been studied using the energy staggering index S(I) as a function of spin I. The unfavored signature index was found lying lower than the favored one. A systematic look at the features of this signature inversion in a series of nine lighter rare earth nuclei in the region around A \sim 160 (Z~=~65-75, N~=~89-101) are presented. The analysis reveals an anomalous signature splitting for this configuration. The magnitude of signature splitting at low spins decreases as the proton number increases. The large signature splitting between the favored and the unfavored bands are observed in ^{156}Tb. The signature inversion point remains fairly constant for nuclei with the same value of N-Z and decreases when N-Z increases.