Low-frequency connectivity is associated with mild traumatic brain injury

Area of Science:

• Neuroscience
• Brain Imaging
• Cognitive Science

Background:

• Mild traumatic brain injury (mTBI), commonly known as concussion, can lead to persistent psychological issues, including attention and memory deficits.
• These post-concussive symptoms (PCS) significantly impair a patient's quality of life.
• While local spectral power changes are known in mTBI, large-scale functional brain network connectivity alterations remain under-explored.

Purpose of the Study:

• To investigate large-scale functional brain network connectivity in individuals with mTBI using magnetoencephalography (MEG).
• To explore the association between altered brain connectivity patterns and secondary psychological sequelae in mTBI.
• To determine if specific network and frequency alterations contribute to cognitive and behavioral deficits post-mTBI.

Main Methods:

• Utilized non-invasive magnetoencephalography (MEG) to assess resting-state functional connectivity in mTBI patients (n=20) and healthy controls (n=21).
• Analyzed local spectral power and large-scale connectivity metrics, focusing on inter-regional amplitude correlations across different frequency bands (delta, theta, alpha).
• Conducted exploratory analysis to correlate connectivity patterns with mTBI symptoms such as inattention, anxiety, and depression.

Main Results:

• Observed a trend for atypical slow-wave power in subcortical, temporal, and parietal regions in the mTBI group.
• Found significant long-range increases in amplitude envelope correlations in delta, theta, and alpha bands among deep-source, temporal, and frontal regions in mTBI patients.
• Identified differential patterns of altered resting-state neurophysiological network connectivity across frequency bands, associated with secondary symptoms.

Conclusions:

• Local spectral power and amplitude correlation measures can define atypical brain networks in mTBI.
• Altered large-scale brain connectivity, varying by network and frequency, likely contributes to overlapping cognitive and behavioral sequelae in mTBI.
• Cognitive difficulties post-mTBI may be mediated by disturbances in network interactions differentially expressed across neurophysiological frequency ranges.