Increased functional connectivity within memory networks following memory rehabilitation in multiple sclerosis

Area of Science:

• Neuroscience
• Cognitive Rehabilitation
• Neuroimaging

Background:

• Memory deficits are a primary cognitive symptom in multiple sclerosis (MS), significantly impacting patients' personal and professional lives.
• Effective behavioral treatments are crucial for neurorehabilitation in individuals with learning and memory impairments.
• The modified Story Memory Technique (mSMT) is a 10-session behavioral intervention designed to improve memory function.

Purpose of the Study:

• To investigate the impact of the mSMT on resting-state functional connectivity (RSFC) within key memory networks in individuals with MS.
• To examine changes in the integrity of the hippocampal memory network and the default network (DN) following mSMT.
• To provide evidence for the efficacy of behavioral interventions in modulating neural network function related to memory in MS.

Main Methods:

• A randomized, placebo-controlled clinical trial was conducted involving participants with MS.
• Resting-state functional connectivity (RSFC) analysis was performed on a subset of participants before and after the mSMT intervention.
• Seed regions were placed in the left and right hippocampus and the posterior cingulate cortex to assess network connectivity.

Main Results:

• The mSMT intervention led to increased connectivity between the left hippocampus and cortical regions associated with visual imagery memory.
• Significant increases in connectivity were observed among critical hubs of the default network (DN) after mSMT.
• These findings demonstrate that mSMT positively impacts the neural networks underlying memory function in individuals with MS.

Conclusions:

• The modified Story Memory Technique (mSMT) is an effective behavioral intervention for improving memory in persons with multiple sclerosis (MS).
• mSMT enhances the integrity of neural networks crucial for memory function, including the hippocampal memory network and the default network.
• This study provides the first evidence that a behavioral intervention can positively alter neural network connectivity related to memory in individuals with MS, supporting its use in neurorehabilitation.