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Is reflex considered a function of autonomic nervous system?

  1. Jul 22, 2016 #1
    I was wondering if reflex is exclusively under the umbrella of the autonomic nervous system, or are there some reflexes that for some reason or definition, that would be associated with another nervous system?

    I did find in some articles that somatic nervous system also has its own types of reflexes.

    And an extra extension to this question, would it be safe to say that every neural activity in the brain is in some direct or indirect way, associated with the autonomic nervous system (and also the somatic)? Basically can autonomic and somatic nervous systems ever "take a break"?

    I guess this can also fall into the category of it depending on what neurotransmitter is being activated?

    Hope that makes sense.
    Last edited: Jul 22, 2016
  2. jcsd
  3. Jul 25, 2016 #2

    Fervent Freyja

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    No, it doesn't exclusively occur through the autonomic nervous system. Both somatic and autonomous reflexes operate through different branches of the peripheral nervous system. Not all neural activity in the brain has to be associated with both at the same time, and sometimes the work is shared and a signal is initially split and sent through both systems for the a quicker reflex action. Sending signals through the spinal cord and back into the muscles gives us the shortest reaction time through it being a shorter pathway, causing the reflex. If you anticipate being given a knee jerk test at the doctors office, then you can try to control the somatic reflex more easily (try this, it's possible).

    Yes, I do think that both take thousands of small breaks periodically throughout the day, and only a few seconds and less is really needed for that. We do have to have time for chemical transport and signalling to maintain all involuntary/voluntary function, that process isn't always so perfect- the heart doesn't beat at the exact same rate throughout the day.Think about how difficult it is to stay still, there are different muscles that have to 'take turns' to keep the body in that position, muscles cannot maintain the same position smoothly, the load must be released and seconds later, picked back up again. But, the signal pathways must have enough time to be cleared, and new chemicals must arrive so that the signal can be re-sent. We can stand on one leg for long periods by alternating between muscles, and involuntary responses in that position can still be countered by voluntary signaling other muscles to help maintain the one-leg stance.

    Yes, neurotransmitters are involved in the process. Some drugs can alter these responses. Especially drugs that lower respiratory function, like muscle relaxers. Alcohol, legal and illegal drugs all compromise the normal process using neurotransmitters, which makes the reflexes more slow and unreliable. People can have all the willpower they wish for when having to walk a straight line for a police officer, but neurotransmitters must have appropriate levels for the action to take place.
  4. Jul 25, 2016 #3
    Great! Thank you @Fervent Freyja
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