MND Revisited

[Chip (OP)]

If you compared the voltages of the CNS/PNS at the fingertips of a person with MND to a control person then worked your way slowly back up the arm and spine to the head then surely you'd see where the precise point(s) of transmisson loss were, right ?

Isn't Mr Invasive Infection-pending Electrode Musk able to do that ?
 
Your idea touches on a promising area in neurodiagnostics: mapping out the electrical activity and nerve conduction at various points in the central and peripheral nervous system to pinpoint transmission loss, especially in conditions like motor neuron disease (MND). This approach could, in theory, reveal the exact areas where signals weaken or drop off due to nerve degeneration.

In MND, the progressive loss of motor neurons disrupts the transmission of signals from the brain to the muscles, leading to muscle weakness and atrophy. Typically, nerve conduction studies and electromyography (EMG) are used to detect abnormalities in nerve and muscle function, but these tests are often focused on the peripheral areas (e.g., arms and legs). Your approach suggests a more comprehensive mapping, from fingertips up to the brain, which could provide valuable data on where degeneration is most pronounced and how it progresses.

As for invasive electrode technology, Elon Musk’s Neuralink and similar ventures are indeed exploring implantable electrodes to monitor and stimulate neural activity. However, current implantable devices focus more on brain-computer interfaces (BCIs) and are not yet optimized for full-body nerve conduction mapping or diagnosing conditions like MND. These devices are typically localized to specific brain regions to assist with movement, sensory feedback, or even typing for people with paralysis. Mapping the entire CNS/PNS system in this way would require an extensive, highly sensitive array of sensors along the entire nervous system, which would be a huge leap in neurotechnology.

Invasive approaches like this may one day assist in diagnosing and monitoring the progression of neurodegenerative diseases, but there are still significant technical and ethical challenges to overcome.

Oooh - go deepest possible!

1. What's an EMG exactly ?

2. What ERPs and what specific voltages do what ?

3. What Oscillatory frequencies ?

I want to help paraplegics but first I wanna disassemble CNS traffic/signals.

You're diving into some fundamental concepts in neurophysiology, and understanding these could indeed be powerful for developing assistive technologies for paraplegics. Let’s break each down:

1. Electromyography (EMG): EMG measures the electrical activity in muscles when they’re activated, either voluntarily or through stimulation. When a muscle contracts, it generates small electrical signals that can be recorded via electrodes placed on the skin (surface EMG) or inserted into the muscle (intramuscular EMG). EMG signals give information about the timing and intensity of muscle activation and can indicate abnormalities in muscle and nerve function. Typical EMG signals in a healthy muscle vary from 0.1 to 5 mV and can fluctuate as quickly as a few milliseconds.


2. Event-Related Potentials (ERPs): ERPs are brain responses that are time-locked to specific sensory, cognitive, or motor events, like seeing a light flash or hearing a sound. They are recorded via EEG and appear as small voltage fluctuations that occur in the cortex in response to these events, often ranging from a few microvolts (μV) up to about 100 μV. Specific ERP components are associated with particular cognitive processes:

P300: Appears about 300 ms after a stimulus, linked to attention and decision-making.

N400: Occurs about 400 ms after a word or sentence, associated with language processing.

MMN (Mismatch Negativity): A negative wave occurring 100-200 ms after an unexpected stimulus, related to pre-attentive processing.



3. Oscillatory Frequencies: The brain’s electrical signals can also be categorized into frequency bands, which represent different types of neural communication:

Delta (1–4 Hz): Associated with deep sleep and some types of neural recovery.

Theta (4–8 Hz): Often linked to memory encoding and retrieval.

Alpha (8–12 Hz): Associated with relaxation and inhibitory control, often dominant during restful wakefulness.

Beta (12–30 Hz): Related to active thinking, focus, and some aspects of movement.

Gamma (30–100+ Hz): Linked to higher cognitive functions, like perception, consciousness, and problem-solving.




If you’re interested in “disassembling” CNS signals, understanding these frequencies could help you decode how different types of signals travel, integrate, or fail in neurodegenerative or neuro-injury conditions.

Interface the two

Yes, EEG (electroencephalography) and EMG (electromyography) can indeed be used together, and when combined, they provide a fuller picture of both brain and muscle activity. By synchronizing EEG and EMG recordings, researchers can observe how the brain’s commands (from EEG signals) translate into muscle actions (captured by EMG) and vice versa.

For example, in studies involving movement and motor control, researchers can use EEG to track the motor cortex’s activity while simultaneously recording EMG from the muscles involved in movement. This combination helps in understanding cortico-muscular coherence, which reveals how well the brain’s signals are coordinating with muscle activity. When there’s a disruption in this pathway—as seen in conditions like paralysis or neurodegenerative diseases—it’s possible to detect it as a mismatch or delay between the EEG and EMG signals.

In the context of assistive technologies, brain-computer interfaces (BCIs) often combine EEG and EMG to help decode intentions in paralyzed individuals. For instance, if a person attempts a movement but the muscles cannot respond (due to a spinal cord injury), the EEG might show motor planning signals even though the EMG remains silent. By capturing this intention at the EEG level, a BCI can be trained to bypass the damaged pathway and activate assistive devices or prosthetics directly.

So, yes, interfacing EEG and EMG is not only possible but is an exciting and essential approach for understanding—and potentially repairing—the communication pathways between the brain and muscles.

How do TENS machine help MND ? Like Zolpidem ? So why haven't you fixed it ? I'll do it in 5 minutes !