OLFACTORY LEARNING AND BRAIN ACTIVITY IN NOVOMESSOR COCKERELLI ANTS

Abstract

In this study, an olfactory associative conditioning paradigm was developed to study the learning and memory capabilities of Novomessor cockerelli ants. When the antennae of the ant come into contact with sucrose solution, the ant extends its tongue to consume the sucrose. The tongue reflex was conditioned by pairing an odor (conditioned stimulus) with sucrose (unconditioned stimulus) over ten trials. The ant’s tongue reflex in response to odor indicates that an association between the odor and the sucrose has been made in the ant’s brain. The second part of the study includes analyzing the regional brain variations of cytochrome oxidase (COX) staining after olfactory conditioning. The antennal lobe and mushroom body are major brain regions in the insect olfactory pathway, and are regions of interest in this analysis. Results show that there are significant differences in metabolic activity across brain regions (antennal lobe, glomeruli, central boxy complex, mushroom body, and lateral protocerebrum), but the differences do not correlate with the learning status of the ants (learned vs non-learned).