Synchronized neural rhythms in rat hippocampal CA1 region and orbitofrontal cortex are involved in learning and memory consolidation in spatial goal-directed tasks.
10.12122/j.issn.1673-4254.2025.03.05
- Author:
Lingwei TANG
1
;
Jiasong LI
1
;
Haibing XU
1
Author Information
1. Department of Neurobiology, School of Basic Medical Sciences, Southern Medical University, Guangzhou 510515, China.
- Publication Type:Journal Article
- Keywords:
goal-directed task;
hippocampal CA1;
neural rhythms;
orbitofrontal cortex
- MeSH:
Animals;
Rats;
Rats, Long-Evans;
CA1 Region, Hippocampal/physiology*;
Memory Consolidation/physiology*;
Prefrontal Cortex/physiology*;
Maze Learning/physiology*;
Goals;
Male;
Memory/physiology*;
Learning/physiology*
- From:
Journal of Southern Medical University
2025;45(3):479-487
- CountryChina
- Language:Chinese
-
Abstract:
OBJECTIVES:To investigate the neural mechanisms of rhythmic activity in the hippocampal CA1 region and orbitofrontal cortex (OFC) during a spatial goal-directed task.
METHODS:Four long-Evans rats were trained to perform a spatial goal-directed task in a land-based water maze (Cheese-board maze). The task was divided into 5 periods: Pre-test, Pre-sleep, Learning, Post-sleep, and Post-test. During the Learning phase, the task was split into two goal navigation and two reward acquisition processes with a total of 8 learning stages. Local field potentials (LFP) from the CA1 and the OFC were recorded, and power spectral density analysis was performed on Theta (6-12 Hz), Beta (15-30 Hz), Low gamma (30-60 Hz), and High gamma (60-90 Hz) bands. Coherence, phase-locking value (PLV), and phase-amplitude cross coupling (PAC) were used to assess the interactions between the CA1 and the OFC during learning and memory.
RESULTS:During the task training, the rats showed consistent rhythms of OFC neural activity across the task states (P>0.05) while exhibiting significant changes in Beta and High gamma rhythms in the CA1 region (P<0.05). Coherence and PLV between the CA1 and the OFC were higher during goal navigation, especially in the stable learning phase (Stage 8 vs Stage 1, P<0.01). The rats showed stronger cross-frequency coupling between CA1-Theta and OFC-Low gamma in the Post-test phase than in the Pre-test phase (P<0.05).
CONCLUSIONS:Learning and memory consolidation in goal-directed tasks involve synchronized activity between the CA1 region and the OFC, and cross-frequency coupling plays a key role in maintaining short-term memory of reward locations in rats.
