The role of the anterior insular cortex in the remote contextual fear memory retrieval

• Grant number: 24/20111-6
• Support Opportunities: Scholarships in Brazil - Master
• Start date: May 01, 2025
• End date: August 31, 2026
• Field of knowledge: Humanities - Psychology - Physiological Psychology
• Principal Investigator: Raquel Vecchio Fornari
• Grantee: Lorena Vido Lopes
• Host Institution: Centro de Matemática, Computação e Cognição (CMCC). Universidade Federal do ABC (UFABC). Ministério da Educação (Brasil). Santo André , SP, Brazil

Abstract

Episodic or contextual memories are long-term explicit memories that contain specific information about the space and time (context) of the event that generated their acquisition, with the characteristic of losing specificity as they mature. Changes occurring in the neural circuits involved in the encoding, storage, and retrieval of memories are called systemic memory consolidation. Brain areas associated with these different stages of memory may show changes in co-activation over time, organizing into neurocognitive networks such as the Salience Network (SN) and the Default Mode Network (DMN). A specific cortical region, called the anterior insular cortex (aIC), classically involved in the detection of relevant information and the expression of fear and anxiety, is associated with the SN and has controversial functional roles in various stages of memory. In contextual fear conditioning (CFC), aIC activity during memory retrieval seems to be associated with training intensity and retrieval time, with greater activation observed after strong training and only in remote time points. This suggests an important role of the aIC in the maintenance and retrieval of strong and generalized contextual fear memory. In this project, we aim to verify whether the aIC is necessary for the retrieval of remote contextual fear memory, after strong training, as well as to evaluate its interactions with other brain areas during long-term memory retrieval. For this, we will use Wistar rats that will undergo the CFC task training (3-foot shocks, 1 mA, 1s) and will be tested 28 days later. The animals will undergo surgery to implant of guide cannulas in the anterior insula for temporary pharmacological inactivation before the test. At the end of the behavioral task, the animals will undergo a perfusion process for brain collection. The brain tissue will be prepared for immunohistochemistry assay, to investigate how the inactivation of the aIC alters the dynamics of SN and DMN engagement during memory retrieval.