Cortico-hippocampal system dynamics during contextual fear conditioning

• Grant number: 07/08426-6
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)
• Effective date (Start): June 01, 2008
• Effective date (End): February 29, 2012
• Field of knowledge: Biological Sciences - Physiology - Physiology of Organs and Systems
• Principal Investigator: Koichi Sameshima
• Grantee: Ana Carolina Bione Kunicki
• Host Institution: Faculdade de Medicina (FM). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated research grant: 05/56464-9 - Neuroscience Imaging Center at University of São Paulo Medical School, AP.CINAPCE.TEM

Abstract

The theta rhythms are slow-wave activities (4-12 Hz) present during wakefulness and paradoxical sleep. In rodents and humans, theta activity has been related to several cognitive and behavioral functions, including emotion, attention and sensorimotor integrations. During the execution of tasks requiring mnemonic processing, the theta rhythms become prominent. Furthermore, blocking this activity retard acquisition in several learning paradigms. Various cortical and subcortical structures have neurons firing synchronously at the theta range frequency and it might be possible that the cortico-hippocampal system has an important role in the modulation of aversive learning. Thus, the aim of this work is to clarify the electrophysiological and molecular mechanisms that modulate the theta activity between the hippocampus and anterior cingulate cortex during learning. Male Wistar rats will be implanted with microelectrodes built specifically for the record electrophysiological simultaneously from 64 channels distributed in the anterior cingulate cortex and hippocampus during the performance of contextual fear conditioning task. The immunohistochemical analyses of immediate early genes, Arc (Activity-regulated cytoskeletal-associated), c-fos (FBJ osteosarcoma oncogene) and Egr1 (Early growth response), related to learning will identify areas of neuronal activation involved in the learning task in hippocampus and anterior cingulate cortex. By studying multichannel electrophysiological recording we will analyze the dynamics of interaction between these functionally correlated areas through partial directed coherence and phase synchrony methods to reveal information flow dynamics during theta rhythms as well as their functional significance during task learning process. (AU)

Academic Publications

(References retrieved automatically from State of São Paulo Research Institutions)

KUNICKI, Ana Carolina Bione. Cortico-hippocampal system dynamics during contextual fear conditioning. 2012. Doctoral Thesis - Universidade de São Paulo (USP). Faculdade de Medicina (FM/SBD) São Paulo.