Organisation neuronaler Netzwerke zur Raumorientierung im Gehirn der Madeiraschabe Rhyparobia maderae und der indischen Riesengottesanbeterin Hierodula membranacea

Insects possess relatively simple nervous systems, which, despite their small size enable them to exhibit impressive navigational behaviors. These facts make them attractive subjects for research to explore and understand neural networks. Their brain consists of fused ganglia and is further divisible into the proto-, deuto-, and tritocerebrum. These components vary in their degree of fusion and prominence across different species and are further subdivided into neuropils. Neuropils are distinct areas where neurons form synapses, and so characterized by a high concentration of synapsin. Synapsins constitute a conserved group of proteins expressed in the brain. They are predominantly found at presynaptic sites, and are involved in the release of neurotransmitters. A particularly prominent and evolutionarily conserved neuropil group is the central complex. It is located centrally in the brain, and controls the spatial orientation of the animals based on multiple sensory inputs. The architecture of this neuropil group, consisting of the central body, protocerebral bridge, and noduli, is highly conserved among insects. It varies in the deeper structure and form of individual neuropils across different species, created by complex systems of central complex neurons: columnar, tangential, and pontine neurons. Understanding the morphology and expression of these structures is essential for comprehending neural networks and their functions. This doctoral thesis focuses on the neuroanatomy of two dictypteran insects, the Madeira cockroach Rhyparobia maderae and the giant Asian mantis Hierodula membranacea with detailed examination of central complex of the cockroach at the neural level.