Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Medical The 6th Sense

  1. Jan 28, 2007 #1
    We all know we have 5 sense. But I wanna know do we have 6. Besides the 5 known there's another one......balance. The organs in our ears filled with fluid allow us to sense our bodies position with respect to gravity. SI diesn't that count as one of the senses?
  2. jcsd
  3. Jan 28, 2007 #2

    D H

    Staff: Mentor

    Were are taught as children that we have five senses. This is a simplistic view, and is obviously incorrect.

    The vestibular system comprises multiple sensory organs. The semicircular canals that measure rotation operate quite differently than the otoliths that measure acceleration. So is balance one sense or two?

    The thermoceptors that sense temperature operate quite differently from the pressure sensors that we equate with "touch". The ability to sense heat is a sense distinct from the classical five senses.

    The nociceptors (pain receptors) are distinct from the pressure sensors associated with touch as well. The pain receptors detect chemical signatures of damage. Pain appears to be yet another sense.
  4. Jan 28, 2007 #3
    Well touch and feeling can all be seen as one group. Balance and movement would be another.

    WHo says we can't have 6. Pluto isn't a planet nowadays so I can't see why our senses can't be altered.
  5. Jan 28, 2007 #4
    Everyone knows that the sixth sense is the sense of humour :rofl:
  6. Jan 28, 2007 #5
    It doesn't count as one of the five senses because it is purely intrinsic. It tells you about yourself, but nothing about the world around you.

    I think there's a longer list that includes the intrinsic senses, and there are more of them than just balance. At a minimum, there's also the somatic sense of where your limbs are at any given time. I remember that was definitely one of the others. I think there's about three intrinsic senses that are considered distinct from each other.
  7. Jan 28, 2007 #6
    Still balance has to dow ith your body relative to the outside world.
  8. Jan 30, 2007 #7


    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    Sensory perception involved in the vestibular system (required for balance) involves tactile information, both of the fluid moving along the cilia within the inner ear, and of proprioceptors around the body that relay tactile information of the position of your body. Visual information can also be incorporated in order to provide a sense of where your body is positioned in space.

    Balance isn't a sense, it is a body function that requires multiple forms of sensory information to be incorporated and relayed to the motor neurons and then muscles. It makes no more sense (no pun intended) to call balance a sense than to call walking or eating a sense.
  9. Jan 30, 2007 #8
    Well why do we call it your sense of balance? Be it internal it is a sense.
  10. Jan 31, 2007 #9


    User Avatar
    Homework Helper

    Nuklear, that's what a dictionary is for. It's not like Moonbear invented the term.
  11. Jan 31, 2007 #10


    User Avatar
    Homework Helper

    As you can see, 'sense of balance' is meaning #4, whereas balance is not considered to be a sense (meaning #1).
  12. Jan 31, 2007 #11
  13. Jan 31, 2007 #12
    Correct me if I'm wrong about this, but isn't there an unofficial 6th sense dealing with awareness of body parts? Let me explain.

    If we close our eyes, we know exactly where our limbs that are moveable are. However if one experiences sleep paralyises (when you're body is technically asleep however you gain awareness) we cannot physically move our body parts. However in this state of mind, you can believe that you moved however your body is stationary. I have experienced sleep paralysis many times (mostly volunatairly to induce lucid dreams.) It's so weird because you can tell your mind to roll on your side, and it feels like your body has repositioned, however you know for a fact that you are still lying on your back (you can barely see out a crack in your eye.)

    I believe this would also explain the missing limb pheonemena.. where one who is missing a limb strangely enough still feels (or more accurately is aware) his or her limb, or more importantly can feel the "pain" where their limb no longer exists.

    Another example of this would be if you closed your eyes, and touched your nose, ear, nipple, elbow or anything.. There is some extra bodily sense of awareness.
    Last edited: Jan 31, 2007
  14. Feb 1, 2007 #13


    User Avatar
    Gold Member

    Here is the 6th.

    2007 Jan 5;144(1):356-67. Epub 2006 Oct 25. Related Articles, Links
    Evidence of a nonlinear human magnetic sense.

    Carrubba S, Frilot C 2nd, Chesson AL Jr, Marino AA.

    Department of Orthopedic Surgery, Louisiana State University Health Sciences Center, P.O. Box 33932, 1501 Kings Highway, Shreveport, LA 71130-3932, USA.

    Human subjects respond to low-intensity electric and magnetic fields. If the ability to do so were a form of sensory transduction, one would expect that fields could trigger evoked potentials, as do other sensory stimuli. We tested this hypothesis by examining electroencephalograms from 17 subjects for the presence of evoked potentials caused by the onset and by the offset of 2 G, 60 Hz (a field strength comparable to that in the general environment). Both linear (time averaging) and nonlinear (recurrence analysis) methods of data analysis were employed to permit an assessment of the dynamical nature of the stimulus/response relationship. Using the method of recurrence analysis, magnetosensory evoked potentials (MEPs) in the signals from occipital derivations were found in 16 of the subjects (P<0.05 for each subject). The potentials occurred 109-454 ms after stimulus application, depending on the subject, and were triggered by onset of the field, offset of the field, or both. Using the method of time averaging, no MEPs were detected. MEPs in the signals from the central and parietal electrodes were found in most subjects using recurrence analysis, but no MEPs were detected using time averaging. The occurrence of MEPs in response to a weak magnetic field suggested the existence of a human magnetic sense. In distinction to the evoked potentials ordinarily studied, MEPs were nonlinearly related to the stimulus as evidenced by the need to employ a nonlinear method to detect the responses.

    PMID: 17069982 [PubMed - in process]
  15. Feb 3, 2007 #14


    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    Thanks, somasimple! (And welcome back! I haven't seen you in what seems like ages.)

    Nexus, what you are describing is known as proprioception, or the knowledge of where one's limbs are in space without looking at them. This is also related to the same sensory systems as are involved in balance. The "phantom limb" symptoms that amputees experience are due to the cutting of the nerves supplying those limbs. There is redundancy in the interpretation of sensory input, generally to two spinal nerves above and below the one that receives input from a particular motor or sensory nerve, to allow compensation for damage to peripheral nerves without loss of function. When a limb is amputated, this compensation is still present where the spinal nerves and brain "assume" it is just a damaged nerve rather than a missing limb and still perceive a limb that is not present. Actually, the fact that one "perceives" a non-existent limb should indicate it is not an actual sensation, but a compensatory function of the brain.
  16. Feb 7, 2007 #15


    User Avatar
    Gold Member

    Thanks. I have less time because I'm unfortunately very busy with the site.
  17. Feb 7, 2007 #16


    User Avatar
    Gold Member

    It is a real sensation at all, induced by memory and somato sensory cortices.
    Brain maintains and adjusts maps of the whole body. Sometimes, when a limb is missing, brain uses an old "snapshot" of it. It creates of course many problems.

    ps: the explanation you gave about spinal organisation is not really accurate since a nerve has often two or three roots to consider and redundancy doesn't work in case of a limb since you have a blank on several spinal roots. (A limb takes 5/7 spinal roots).

    BTW, the neighboor axons (up and down) are used in the discriminatory sensitive process. They improve the perception.
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?

Similar Discussions: The 6th Sense
  1. Human senses (Replies: 3)

  2. What are senses? (Replies: 16)

  3. Trusting our senses (Replies: 10)