Morphology and function of the hemiellipsoid bodies of the crab Neohelice granulata; their role as high-order memory centers

FRANCISCO MAZA; JULIETA SZTARKER; FERNANDO LOCATELLI; ALEJANDRO DELORENZI

Brisbane

Conferencia; ICN 2018; 2018

ISN

Despite unique adaptations that animals have in accordance to their lifestyle and the conditions of theenvironment in which they live, many of the basic mechanisms that allow them to learn and store acquiredinformation to modify their behavior are conserved across evolution. In this regard, the molecular machineryinvolved in neural plasticity and the dynamics of the memory processes are common throughout vertebrate andinvertebrate species. Theoretically, this occurs because the circuitry and brain organization of the ancestralbilateral animal has already provided an effective solution that allows the acquisition of different kinds ofinformation and the organization of memories as internal representations. One of the iconic neural structures thatbear this role in vertebrates is the hippocampus, also referred to as archicortex since it is phylogeneticallyconsidered to be the oldest brain region. In invertebrates, the corpora pedunculata or mushroom bodies aresupposed to play a similar role as the archicortex of vertebrates. Here, we present functional, neuroanatomicaland immunohistochemical data of the hemiellipsoid bodies of the crab Neohelice granulata. This structure hasbeen historically proposed to have a similar function to that of the mushroom bodies of insect. N. granulata showshemiellipsoid bodies that are similar to those described in other true crabs, and its structure resembles that ofcalyx-less corpora pedunculata that are observed in several insect species.