Functional connectivity pattern during rest within the episodic memory network in association with episodic memory...

Area of Science:

• Neuroscience
• Psychiatry
• Cognitive Science

Background:

• Episodic memory deficits are common in bipolar disorder (BD).
• Altered intrinsic functional connectivity is a potential mechanism underlying these memory impairments.
• Previous research suggests disrupted neural networks in BD.

Purpose of the Study:

• To investigate the intrinsic functional organization of the episodic memory network at rest in individuals with BD.
• To test the hypothesis that aberrant functional connectivity in episodic memory regions is present in BD patients.
• To explore the relationship between functional connectivity and episodic memory performance in BD.

Main Methods:

• Functional magnetic resonance imaging (fMRI) was used to assess brain activity in 21 BD patients and 21 healthy controls during a resting state.
• Seed-based analysis (SBA) was employed, utilizing regions of the episodic memory network as seeds.
• Functional connectivity (FC) scores were correlated with episodic memory task performance.

Main Results:

• BD patients exhibited decreased functional connectivity (FC) within frontal regions and between frontal and temporal/hippocampal/limbic areas compared to controls.
• Increased FC between frontal and limbic regions was observed in BD patients.
• A significant positive association was found between reduced fronto-frontal FC and episodic memory performance in BD.

Conclusions:

• Task-independent functional connectivity alterations in the episodic memory network are evident in bipolar disorder.
• Dysfunctional fronto-frontal and fronto-limbic connectivity at rest may contribute to memory impairments in BD.
• These findings provide valuable insights for understanding the neurobiological underpinnings of BD and its impact on memory.