Optical imaging of different activation patterns in the lateral protocerebrum of the crab Chasmagnathus granulata during the construction of memories that can or not be expressed in long term

MAZA FRANCISCO; LOCATELLI FERNANDO; DELORENZI ALEJANDRO

Huerta Grande, Cordoba

Congreso; XXVI Congreso Anual Sociedad Argentina de Neurociencias; 2011

Sociedad Argentina de Neurociencias

Memory is a sequence of processes that include making an internal representation, storing and retrieving of information. Within Chasmagnathus´s Context Signal Memory (CSM) paradigm, an iterative Visual Danger Stimulus (VDS) induces a change in behaviour, from escape to freeze. We focus on Weak (WTP) and Strong Training Protocols (STP). Long term memory (LTM) expression is disclosed after STP but not after WTP. Initially designed to induce STM, WTP leads also to a latent LTM potentially reactivated and expressed after improving reconsolidation. Crab´s lateral protocerebrum, formed by the medulla terminalis and hemiellipsoid bodies neuropils, is proposed as higher-order integration center involved in sensory processing and memory storage. Using Calcium imaging we are evaluating whether, the amnesic effect of several drugs described to interfere with LTM, are due to interference on memory storage or to modulation of memory expression. Our preliminary results showed that specific changes in activity induced by training and short-term tests (30´) were abolished by an NMDA-receptor antagonist. This project´s goal is to show that LTM expression is a distinct attribute of LTM storage.