Neuronal plasticity in the Lateral Protocerebrum of Neohelice reflects long-term memory persistence independently of its expression

MAZA, FRANCISCO JAVIER; LOCATELLI, FERNANDO; DELORENZI, ALEJANDRO

Huerta Grande, Córdoba

Congreso; XXVIII CONGRESO ANUAL DE LA SOCIEDAD ARGENTINA DE INVESTIGACION EN NEUROCIENCIAS; 2013

SOCIEDAD ARGENTINA DE INVESTIGACION EN NEUROCIENCIAS

Results from our group have shown that behavioral expression is not necessary for memory reactivation and labilization. In this view, memory persistence (evaluated by the capacity of memory to be reactivated and become labile) should be considered a memory attribute independent of memory expression. Here, we use in vivo imaging to analyze neural activity in the Lateral Protocerebrum (LP) of the crab Neohelice granulata during and after two different trainings that induce: a) long-term memory that is behavioral expressed, or b) long-term memory that is not expressed but evident because it is reactivatable. In addition, we evaluate the effects of amnesic agents that interfere with memory persistence or with memory expression. The results show that, after training, there is a reduction in the neuronal activity in the LP specifically elicited by the training stimulus. This reduction was observed after training protocols that induce memory persistence independently of its long-term expression. Treatments proposed to interfere with memory persistence (NMDA receptor antagonist MK801 1ug/g and muscarinic cholinergic antagonist Scopolamine 5ug/g) block the changes induced by training. These findings add system level support to the hypothesis that expression and persistence are different memory attributes, showing that neuronal plasticity in the LP induced by trainings reflects long-term memory persistence but not its behavioral expression. 222