Age-related changes in cortical depth and neuronal cell packing density in cerebral cortex of goat

The present study was conducted to study age-related changes in the left temporal cortex of cerebrum related to cortical depth and neuron cell packing density. Twenty goats were equally grouped in two groups as Gr-I (9–12 monthsold) and Gr-II (>15 years of age). The neuronal count was based on a computer assisted manual method involving cell differentiation in Nissl-stained sections under the microscope. It was found that the cortical depth differed for total cortex among the groups. The neuronal cell packing density (Nv) was greater in Gr-II than Gr-I for the total cortex depth (P<0.05). On the contrary the cell packing density for layer II and IV was greater in Gr-I than Gr-II (P<0.05). This suggested that the temporal lobe as a functional unit has a different ratio of cell packing density at young and old age, which could have implications for the age-wise differences in recognition and behavior. It was concluded that at old age, there was reduction in cortical depth with an increase in neuronal cell packing density.