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The frequency of the human body is?

  1. Apr 24, 2008 #1
    I don't want to ask this question in a New Age metaphysical type of way so please don't interpret it as such. What frequency does the human body run at?

    Does this question make sense or is it too broad?

    I will try to fire off a frew seperate examples of what I mean so that the question is more answerable.

    1) Human Brain - neuroscientists find a range of a few Hz to 20 plus Hz. We've all heard the terms Alpha waves, Beta waves, Delta waves and Theta waves to describe the different brain states. What is this measurement of exactly, in a physical sense?

    2) Membrane Potentials - we all know they govern tons of biological transport systems, like the classic ion channels where ions of CL-, Na+, K+ pass through membrane channels that have voltage potentials. Does it make sense to ask what frequency these work at?

    3) Heart Beat - Clearly this can be measured in Hz. If your heart beats 120 bpm, its beating at 2Hz.

    4) Your skin - Human's are constantly radiates thermal radiation off their skin's surface, I'm guessing a frequency of ~1000Hz.

    5) Vision - The human brain processes visual images at ~60Hz in brightly lit conditions.

    So those examples are a few that I could think of off hand. Personally, of the 5 I'd choose Vision as the best fit for an answer when someone asks what frequency the human body runs at. It bothers me that so many unchecked people use 'frequency' to describe mystical things, in a sort of intellectual cop out. Ok, rant over, but seriously is there a better measure of the human body's frequency than vision?
  2. jcsd
  3. Apr 25, 2008 #2


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    This is not far fetched at-all.

    In fact, Helicopter pilots in Vietnam often reported difficulties and had accidents as a certain rotor speed cause vibrations which coincided with the resonant frequency of a part of the human eye.

    The points made in the OP are irrelevant though. The vibrational properties of a system are purely mechanical. The word frequency has multiple usages; frequency of EM waves, frequency of mechanical oscillation, frequency of occurance. You have used all these.

    The question "what frequency does the human body work at?" is ambiguous and basically invalid. In the case of mechanical frequency you could ask what the resonant frequency of a local part of the body is.
    Last edited: Apr 25, 2008
  4. Apr 25, 2008 #3
    Various parts of the body do indeed have sympathetic frequencies (I edited this because resonant is not the correct term). In the late 50s and early 60s, the US Army did research on using this as a tactical weapon - for example inducing diarhrea as a way of quickly demoralizing enemy troops.

    I used to do a classroom demonstration (in more innocent times when you could still do stuff like this) with low frequency sound. I knew, for example, the frequency response of the bladder and could usually send several students scurrying for the loo.
    Last edited: Apr 25, 2008
  5. Apr 25, 2008 #4


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    I think you've answered your own question in the OP. There is no single frequency that the human body functions at, so there is no answer to your question other than, "No."
  6. Jun 8, 2009 #5
    What do you mean by cycles? You can't give such a definitive answer without explaining what you mean by the 70Hz and 72Hz, you must detail what you mean.
  7. Jun 8, 2009 #6


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    I think it runs at many frequencies - otherwise, how would you be able to "catch the beat" of many different types of music? Look up "limit cycle" and "entrainment". Possibly circadian rhythm too.
  8. Jun 9, 2009 #7
    Much too many variables to come up with an "human body frequency", one could come up with some value at a push, but I it would be of exactly no value tbvh, unless you like to delight guests at a dinner party with strange, odd or ultimitely useless facts (I'm not the only one I hope?!) :)
  9. Jun 10, 2009 #8
    Huh what do you mean by catch a beat? Cilia in the inner ear attenuate varying frequencies of sound, generally ranging from 20Hz to 10,000Hz. Are you talking about bobbing your head to the most prominent drum beat?
  10. Jul 15, 2009 #9
    It is true that the heart beats at 1.2 Hz..but the human brain works in a mysterious way you could even say is has more Hz then any part of the human body, but like i said the human brain is a mysterious organ..what I'm trying to say is that the answer you are looking for it cant be answered, until we get to know the human brain a little more.
  11. Aug 14, 2009 #10
    Hey guys--

    I have been asking myself the same question but being a bit more of an experimentalist, I have been measuring my (and my wife's) frequency and voltage with an oscilloscope...I have found that on the human body's skin (from touching the probes to the hands, arms, leg, foot, back) a frequency of about 68Hz and it seem the gentleman referring to 70Hz is backed up by my measurement.

    I though, "that is pretty close to the power lines (60Hz), wonder if there is some sympathetic resonance going on with the human body or something". I've built a lot of circuits and electronics but have never thought about it or applied it in terms of the human body and it has really got me thinking...

    Also, sort of interesting that the waveform is closest looking to a squaretooth wave...I would have thought it would be a sinewave which is much more prevalent in nature. Anyhow, I was searching google to find out more about this oscillation and first found this forum and thought I would add my contribution. I will double check to see if this frequency is all on the positive side or if it actually changes direction (goes negative). I am not near my equipment for a double check now but I think it does reverse direction and I am really perplexed on where in the body this is originating from.

    I would love to learn more if someone can point me in the correct direction.

  12. Aug 21, 2009 #11
    I suspect your oscilloscope is picking up electrical impulses from your beating heart. After all 70Hz is about the resting rate of the heart for adults. Go for a jog or do a few pushups and see if it goes up. If it does, check your pulse to see if it matches.
  13. Aug 21, 2009 #12


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    Heart rate is 60-70 beats per minute, not per second (Hz). More likely he's picking up AC Mains noise.
  14. Aug 21, 2009 #13


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    What really bugs my *** right now is that I have a chart somewhere, released by NASA in the late 60's or early 70's, that shows the sympathetic frequencies of about a dozen different body parts, and I have no clue as to where it is. I haven't seen it in close to 40 years, but I know that I've got the damned thing some place.
  15. Aug 22, 2009 #14


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    The frequency of the human body is 10 Hz.

  16. Nov 3, 2009 #15
    I'll start out by saying that it's late; I have to work in the morning, and It's pretty cool that I found this site.

    Ironically, I've been asking myself this very question for years now, and again tonight. Just tonight! And, I believe this to be one of the most thoughtful answers I’ve ever heard directed toward answering this question in a non mystical pseudo scientific kind of way. Again, it's only getting later, and for now, suffices to say that my first search engine quire landed me here on a site which appears to dedicate its forum to bringing to fruition the answers to this question.
    I would like to share my thoughts on the wealth of answers to this question hopefully within the next few days, and to also thank Chaos' lil bro Order for posting this brain teaser!

    Be well.

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