Neuronal classes and their specialization in the corticoid complex of a food-storing bird, the Indian House Crow (Corvus splendens)

Neuronal classes and their specialization in the corticoid complex of a food-storing bird (the Indian House Crow, Corvus splendens Vieillot, 1817) have been investigated using Golgi and Cresyl-violet methods. The aim of present study is to observe the neuronal characteristics of corticoid complex of the House Crow (food-storing bird) and to compare them with that of a nonfood-storing bird (the Strawberry Finch, Estrilda amandava = Amandava amandava (L., 1758)). Three main neuronal classes, viz. projection neurons, local circuit neurons, and stellate neurons, have been identified in both intermediate corticoid area (CI) and dorsolateral corticoid area (CDL) based on soma shape, arrangement of dendrites around the soma, and axonal projection. Projection neurons have four neuronal subtypes: multipolar, pyramidal, pyramidal-like, and horizontal cells. It seems that the specialization in pyramidal, local circuit, and pyramidal-like neurons show advantages in the House Crow as a food-storing bird for better memory, cognition, and connectivity in corticoid complex. This is the first study of its kind that provides information regarding neuronal classes within the corticoid complex of a food-storing bird and a comparison between a food-storing bird (House Crow) and the only available study on a nonfood-storing bird (Strawberry Finch).