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Is there a time lag?

  1. Jun 25, 2013 #1
    Is there a time lag between the moment our brain thinks and the moment we actually know we're thinking. To elaborate and make it more clear let me put it like this:
    Whenever we think, we feel like we 'hear' whatever we think, so is there a time lag between the actual moment when our brains thinks about something and the moment we kinda 'hear' it?
    Last edited: Jun 25, 2013
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  3. Jun 25, 2013 #2


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    Sounds like you are referring to reflex action. The brain has a reflexive response to threats, but, this can be conditioned [e.g., military training].
  4. Jun 25, 2013 #3
    Not reflex actions, I am talking about common thinking process, like you're sitting and thinking about anything.
  5. Jun 25, 2013 #4
    Your question is a little vague. If it could be rephrased as: "Is there a time lag between when we first hear something (that is, become aware of a sound) and when we recognize the sound based on our prior experience such as recognizing language or a particular voice?", there is, but it would normally be very short, some fraction of a second most likely. If the sound is unfamiliar it would likely take longer or perhaps not be recognized at all. The time lag would depend on our level of training/familiarity with the sound patterns we are hearing.
    Last edited: Jun 25, 2013
  6. Jun 25, 2013 #5
    This is a very famous issue in cog sci circles. The guy that kicked it off was Benjamin Libet. I refer you about 3 decades of debate in a variety of journals. Your question is actually more interesting than you might think. His idea is, get this, that your brain registers a percept, it takes on the order of a half second for you to become aware of it, but then you retroactively back date the event consciously in order to utilize the information "real time" in your current environmental circumstance. Sounds nuts, I know. But it's not crackpottery, he's the real deal, and commands the debate of the best neuroscientists still.

  7. Jun 25, 2013 #6
    Actually my question is not about sound, please read it again.
  8. Jun 25, 2013 #7
    Oh! So it's a famous issue, I was actually hesitant in asking this question, as I felt that the question will be downplayed immediately.
  9. Jun 25, 2013 #8
    OK. I misunderstood you. What DiracPool is referring to has to do with "volitional" acts and whether we in fact have free will. The idea is that the brain acts on a decision before we realize we made a decision. We apparently think we have made a choice when the brain has already begun implementing that choice. The time lag here involves the realization we have made a "choice". Most neuroscience workers do not believe there is such a thing as free will.
    Last edited: Jun 25, 2013
  10. Jun 29, 2013 #9
    So if I am reading what is posted here I am retroactively backdating the words I see and the comprehension of their meaning to a certain time period so that it only appears to me to be in real time.

    I can believe that when I focus my eyes on a certain word at different places on the screen, and I can "feel" the time lag from the focus to the comprehension of the word or icon, but 500ms for reading.

    So now when I compose a verbose message, I am actually thinking 0.5 ms and typing 0.5ms in the past but I really do feel that I am typing now. Kind of crazy stuff.

    Or for that matter being at bat in a game of baseball and making a decision to swing or not at a pitch. An approximate 90mph pitch will cross the home plate in 0.40 seconds.

    So item #0 on Libet's experiment (repose) is when the pitcher throws.
    To decide to swing at the pitch or not, I have to be consciously aware that the pitcher has thrown the ball, which would be item #1 - the readiness potential - 0.500 seconds before I swing. I note the position of the ball when I decide to swing -item #2 - 200 ms before I swing. I exercise my decision at 0ms - item #3.
    Has the ball already crossed home plate when I swing but I can unconsciously backdate the swing and hit a home run?

    Any experiments on a baseball hitter or other athletes, versus us regular folk on this neuro topic?
  11. Jun 29, 2013 #10


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    You do not have to. In addition, you see the motion of the pitcher in advance.

    There is a similar situation in table tennis. Fast balls can be so quick that you have no way to react with your consciousness - but the reaction happens, and afterwards you notice that you moved your hand.
  12. Jun 29, 2013 #11
    I really haven't been following the debate since the late 90's, but from what I can remember, the antedating is used largely to bring parity between cause and effect in consciousness. The experiments show that you make the decision long before your cortex has a chance to process the data, but when that finally does happen, it back dates the event so that you think that you were making decisions in real time. Again, that's just me backdating what I think I knew of the subject to the 90's :confused:

    For some reason, Susan Pockett has taken up the cause to dissect this issue, and there's a history of the debate in one of the journals I referee for, Consciousness and Cognition. You may find some more updated info there. Although it's interesting, I haven't followed the debate in some time because I got burned out on it. But you can see from the back and forth that it arises a lot of passion in people, probably because it hits at the heart of free will. Check this link:


    He also finally came out with a book called "mind-time" shortly before he passed.

  13. Jun 30, 2013 #12
    OK. Thanks. I believe I now understand what Libet's experiment entails regarding the unconscious / conscious you. Took me a day and a half, just 15 minutes ago, but now I am not so sure it was me, or which parts of me... were debating the issue.

    I often did wonder about how someone, and not just atheletes, such as a musician playing notes, a daty entry girl typing on a keypad, a singer keeping tune within a choir or the instrumental music, can do something very well, and do it so well without thinking about it that it takes on the appearance of being just a natural extension of a persons talents. If an individual ( well basically me a one person experiment ) attempts conscious thoughts about the task in which he/she is involved, it quickly becomes bogged down.
    Very interesting.
  14. Jun 30, 2013 #13
    I can well imagine.

    At first, upon reading the Libet link, the half second 'delay' seemed much too excessive for a functioning human - well how can a person even walk without falling flat face after 2 steps. But it is what it is. A much too interesting a subject of which I know little about.
    So, and thanks for the links, as start on investigation.
  15. Jun 30, 2013 #14
    Ages ago, I saw baseball great Willie Mays check his swing and then hit a home on a single pitch. The pitch was a "change up"; a slow speed pitch when a fast ball is expected. A fast ball may take only about 0.45 sec from the pitcher's hand to the catcher's mitt. The 0.5 sec figure for conscious perception of an action (then reset back) may well be an average for a variable. Superior athletes may have tighter conscious control of their actions although the general principle still applies. Of course Mays's eye-muscle coordination may have also been more refined at the subconscious level even for this extraordinary "double clutch".
    Last edited: Jun 30, 2013
  16. Jun 30, 2013 #15


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    I still don't see why reaction times are so important. Your brain can work within less than .5 seconds (with training), but you will only recognize it as conscious decision after the reaction.
  17. Jun 30, 2013 #16
    Possibly. The decision to check his swing could well have been initiated before awareness, but the decision swing again at the same pitch is not something that is at all common. I'm not sure that the studies cited indicate that all actions are initiated before one is conscious of the decision. I may not act on a conscious decision for seconds, minutes or even hours or days. I knew I was going to file for an extension for filing my income tax a month before I filed for an extension.
    Last edited: Jun 30, 2013
  18. Jun 30, 2013 #17


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    If you decide to do something "at some point in the future", you can be aware of that before that point in the future comes, sure. In general, if you have enough time, .5 seconds are not so interesting.

    I think the interesting thing we can learn from the baseball/table tennis examples:
    You can do decisions that look like conscious decisions, without being aware about that decision before you reacted.
  19. Jun 30, 2013 #18
    Ok, here's the deal. It's coming back to me in bits and pieces. There's a main principle in Libet's model that I forgot about, and that's the principle of the "veto." Libet's model is that essentially all actions are initiated involuntarily (withstanding filing for taxes). These involuntary actions or reactions to the current sensory/environmental circumstance are largely reflexive in nature and are initiated at the level of spinal cord reflexes all the way up to more evolved and learned action pattern sequences in the upper brain stem and limbic system. Action based on this subcortical sensory-motor hierarchy is relatively quick. Processing in the neocortex is much slower, and is also the last region of the forebrain to receive these sensory signals.

    Looking at above, and looking at the experimental data, Libet cam up with the model that essentially all action is initiated involuntarily, and that the role of the cortical or conscious or "volitional" brain was to evaluate that reflexive initiative and either allow it to proceed or to "veto" that action. So, as a rough analogy, the decision to swing at a pitch would reflect the involuntary initiation of an action and the check swing would reflect the cortical evaluation of that initation as a bad decision. The execution of the veto is a top-down "volitional" phenomenon coming strait out of the cortex and influencing the fine coordination of the musculature through the cortico-spinal or pyrimidal motor tract. This would completely bypass the much slower route to muscular control that would have to move through the subcortical motor hierarchy.

    Conversely, if the .5 second readiness potential agreed with the initial reflective action, the cortex would simply allow it to proceed and may, in fact, assist its operation through its top-down volitional control. So, in short, the cortical or volitional apparatus of the neocortex mainly serves as a guide or judge of the subcortical systems reactions to various stimuli. To keep its conscious world in order, however, it backdates that governance to make it seem as if the "self" is doing the initiating much of the time.
  20. Jul 3, 2013 #19


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    I'm not sure about this specific question. But there is definitely a lot of related research into brain activity, and how it relates to what the individual actually perceives is going on. For example:
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