Figure 4.

Novel object recognition memory index. A significant decline in memory index was observed in the cadmium and combined (nicotine-cadmium) treatment groups (P < 0.05) when compared with the control. Although nicotine treatment recorded no statistically significant decline in memory index, empirical quantification shows a decline in the memory index versus the control. However, comparing the nicotine treated group with the combined treatment group demonstrates the effect of cadmium in facilitating decline in memory function when coadministered with nicotine, similar to what is observed in tobacco smoke (statistical significance: ^* P < 0.05).