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Updated: May 12, 2026
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Real-Time Fluorescent Measurement of Synaptic Functions in Models of Amyotrophic Lateral Sclerosis
Published on: July 16, 2021
Altered cortical communication in amyotrophic lateral sclerosis
Stefanie Blain-Moraes1, George A Mashour, Heonsoo Lee
1Department of Anesthesiology, University of Michigan Medical School, 7433 Med Sci I, 1150 West Medical Center Drive, Ann Arbor, MI 48105, USA.
Neuroscience Letters
|April 10, 2013
Summary
Amyotrophic lateral sclerosis (ALS) shows altered brain communication. Individuals with ALS exhibit increased feedforward connectivity, potentially compensating for motor neuron loss and aiding conscious processing.
Area of Science:
- Neuroscience
- Neurology
Background:
- Amyotrophic lateral sclerosis (ALS) primarily affects the motor system.
- Functional connectivity studies suggest adaptive brain changes in ALS.
- Disease-related alterations in cortical communication in ALS remain unclear.
Purpose of the Study:
- To investigate directed functional connectivity changes in the brains of individuals with ALS.
- To compare feedforward and feedback connectivity between ALS patients and controls.
Main Methods:
- Recruited individuals with ALS and age-matched controls.
- Recorded electroencephalography (EEG) during brain-computer interface operation over three sessions.
- Measured directed functional connectivity using normalized symbolic transfer entropy.
Main Results:
- Feedback connectivity did not differ significantly between ALS patients and controls.
- Feedforward connectivity was significantly higher in individuals with ALS compared to controls.
- This finding was consistent across a broad EEG spectrum (4-35 Hz) and specific frequency bands (theta, alpha, beta).
Conclusions:
- Increased feedforward connectivity may represent a compensatory mechanism in ALS.
- This compensatory response could help maintain conscious processing despite motor neuron degeneration.
- Feedback connectivity, linked to conscious state, was independent of ALS symptom severity, with implications for assessing consciousness in advanced ALS.
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