Changes in cortical plasticity after mild traumatic brain injury.

Area of Science:

• Neuroscience
• Neurophysiology
• Brain Injury Research

Background:

• Mild traumatic brain injury (TBI) can lead to persistent symptoms, but the underlying neurophysiologic mechanisms remain unclear.
• Objective measures for early brain abnormalities post-mild TBI are lacking, hindering understanding of lasting deficits.

Observation:

• A case study of a concussed individual revealed no abnormalities in MRI, DTI, or neuropsychological evaluations.
• However, neurophysiologic testing showed subclinical abnormalities, including higher intracortical facilitation and altered GABAB-mediated inhibition.

Findings:

• The patient exhibited transient alterations in brain cortical physiology, including abnormal plasticity mechanisms.
• These neurophysiologic changes normalized by 6 weeks post-concussion, despite the absence of anatomical or neuropsychological deficits.

Implications:

• Transcranial magnetic stimulation (TMS) measures may serve as sensitive biomarkers for detecting physiologic brain abnormalities after concussion.
• This highlights the potential of neurophysiologic assessments in identifying early, subclinical changes following mild TBI.