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Quantifying our sense experience

  1. Aug 30, 2017 #1
    I have been thinking about ways to quantify human sense experience. I know our experience of the world is subjective, though the world around is real and objective. How do we quantify our sense experience in order to measure our own subjectivity?

    I am talking in biological, and neurochemical terms, not merely psychological terms.
  2. jcsd
  3. Aug 30, 2017 #2


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    The human sense experience is an intrinsically psychology thing, if you are really talking about the experience part.

    In general, this can be quantified by psychophysical approaches, which compare controlled sensory inputs to clear sensory experience (as reported by the subjects).
    Clear examples of subjectivity of conscious experience varying between different people are the various forms of color blindness. There are many tests to demonstrate this.

    In some cases, the results of pychophysical experiments have been correlated with physiology of sensory processes. Color perception and blindness is also a good example of this.

    There may be more subtle forms of subjective experience, but they would be more difficult to quantify.
  4. Sep 1, 2017 #3
    I think you answered your own question there...in a sense. Meaning that,

    Let's say we re-write your question using a synonym of quantify, "objectify," making the sentence, " How do we (objectify) our sense experience in order to measure our own subjectivity?

    Well, there's the oxymoron, or contradiction. Trying to objectify subjective experience is like trying to make black out of white. They are two contradictory terms on their face. You can buy into that, or not. But the first approximation is that there is a reason that these two polarized terms exist and, arguably, dominate a lot of the consciousness science debate.

    In short, there's no simple answer to this question.
  5. Sep 1, 2017 #4
    In the case of hearing we might measure the level at which a sound became audible to different test subjects, or the one at which it became painful. We might test the ability of individuals to distinguish the difference between two tones.

    All surfaces are rough at some scale. We could determine the point at which a surface no longer felt smooth to different subjects.

    Similar tests might be developed for all the senses. Only once the basic data had been gathered could we begin to establish patterns, trend and significance.
  6. Sep 1, 2017 #5
    That's basically psychophysical measurement, as BillTre mentioned. There's a measure called the Least Notable Difference (LND) and related measures that can provide some quantitation as to things like the shortest distance between two pinpricks you can detect on different parts of your body. SPOILER--the distance is farther on your upper back than it is on your fingertips. From here, we can actually map this data to receptive-field recordings of functional cortical columns in the somatosensory cortex. So here may some sort of mapping between biological and subjective processes. But LND measure all also used in much more subjective realms such as subjective reports as to how happy, self-confident, or stoned you are. Those are a bit harder to measure, although, the argument could be made that some state of the brain is measureable, not necessarily in the mapping of receptive fields, but in some other manifestation of brain state, that we could similary quantify mental such such as love (emotion) and more not-emotive brain states. Welcome to world of modern philosophy and psychology.
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