Organização neural do complexo central no cérebro da abelha: um estudo comparativo

Abstract

In the past few decades, the study of visual perception has been one of the research fields with utmost progress in neuroscience, which aroused intriguing questions about visual processing in the brain. With the aim of answering to these questions, a comparative approach involving different visual systems can importantly contribute to discover commonalities and differences in the neural architecture underlying visual processing. In this context, invertebrate models with relatively simple brains and great visual capacities can strongly contribute to reveal visual processing phenomena that can hardly be accessed in vertebrate models. The honeybee Apis mellifera is considered one of the main animal models for studying visual perception due to the remarkable visual processing capacities displayed by its small brain. Although several behavioral studies have revealed the amazing visual capacities of honeybees at the cognitive level, few studies have been performed to explicitly investigate the neural basis of visual processing. Some neurophysiological and neuroanatomical studies described different functional types of isolate neurons throughout peripheral neuropiles of the honeybee visual system, thus allowing a shallow understanding about the primary mechanisms underlying visual processing. Nevertheless, neurobiological studies on higher order visual processing in the bee brain are scarce. The present work is aimed towards the study of the neural architecture involving the central complex (CC) of the honeybee brain, a protocerebral region that is apparently involved in higher order visual processing, such as visual integration, memory and learning. By using different neuroanatomical techniques, we described some important aspects about the neural organization and the connectivity of the CC in honeybees. In addition, a broad literature review was performed in order to gather information about the neural architecture of the CC in other invertebrate models. We found remarkable similarities between the neural organization of the CC observed in bees and other insect models in neuroscience, such as the fruit fly Drosophila melanogaster and the desert locust Schistocerca gregaria. In this comparative study, we discussed the possible functions of the honeybee CC in visual processing.