Your Fingertips Perform Brain-like Calculations

By Carl Engelking | September 8, 2014 2:54 pm

fingertips touch

Your brain has a lot to think about, so if there’s a way to outsource a few mental tasks to save bandwidth, it’s going to do it. Now researchers have discovered another such workaround: the neurons in your fingertips perform some computational tasks independently of the brain.

Researchers from Umeå University in Sweden demonstrated that nerve endings in our fingertips encode information about touch intensity and shape before those signals ever travel to the brain. Their findings challenge the long-held belief that our skin simply signaled that something was touched, and our brains processed all the bits of information about shape. 

Magic Touch

Pressure-sensing nerves in our fingertips come in two different flavors – Meissner corpuscles and Merkel discs. Meissner corpuscles react to light, fast deformations across the skin, and Merkel discs respond to pressure and slower, deeper impressions on the skin. Researchers hypothesized that these two nerve types worked in harmony to not just pass along sensory info but to actually pre-process it before it reaches the brain.

To test their theory, researchers used a rotating drum with raised edges of various shapes to stimulate the fingertips of 44 volunteers. They monitored neural impulses with an electrode, which was inserted into the median nerve. The various edge shapes on the rotating drum caused volunteers’ fingertip neurons to fire in varying levels of intensity and frequency. Essentially, our fingertip neurons, in a similar fashion as brain neurons, created a code that conveyed information about an edge’s shape.

Clever Fingertips

Their findings, published Sunday in the journal Nature Neuroscience, challenge the long-held belief that neurons in our cerebral cortex performed all the calculations to process touch data. Researchers are conducting more experiments to see if the same fingertip neurons can sense an object’s curvature and direction of motion, which are also typically considered a brain-based function.

 

Photo credit: Chokniti Khongchum /Shutterstock 

CATEGORIZED UNDER: Mind & Brain, top posts
ADVERTISEMENT
  • wylekat

    I had a concept like that for robotics- don’t have it all centralized- use processors for various sensors, and have it and the main processor work together.

  • garedawg

    When I was little and asked my mom why the cat’s tail was always swishing about, she told me that it had its own little brain in the tip. I’m not sure if such a thing has ever been discovered, but maybe it will someday.

    • Sky Kerzner

      That’s quite true for octopus arms — each one has essentially a brain indeed at the base. In mammals it’s almost kind of true, since the spine executes brain-like activity to coordinate muscles.

  • Kathy Phipps

    I’ve always suspected this because if you ask me to tell you a password, I can’t tell you without “typing it out on an imaginary keyboard. Or like not being able to name the order of the keys but can type without thinking about where the keys are.

    • bensabio

      Probably most actual behavior (walking, riding a bike, playing the piano, etc., etc.) uses so-called “muscle memory” and not conscious processes for each movement. But the fact that a behavior is coordinated at subconcious level by no means implies that it is not based on integrated brain funcions. Something like the reflex withdrawal of one’s finger from a painful stimulus is known to be governed by a spinal reflex, independent of brain involvement (an obvious adaptive function) but all these other movements (typing, walking, driving, playing the piano, etc.) definitely are brain controlled but happen much too quickly for conscious decision-making for each movement (although one could alter the movements deliberately at any moment!). There’s a lot more going on in the brain than is dreamed of in your philosophy, Horatio.

      • Sky Kerzner

        Although, recent research suggests that the brain’s role in motor coordination is actually a bit abstracted from the actual motion. For example, the primary motor cortex seems to code more for the general direction of movement in space (like moving your arm to the left), while synapses in the body, especially the spine, determine the specific muscle activations required to execute that motion.

        • bensabio

          Thanks for that clarification, Sky. Of course, you are correct about extra-cerebral control of detailed muscle activity, and I should have considered that in my previous post! I wonder if higher-level coordination (e.g, fine finger movements in playing music or writing – or even speaking!) could be somehow imprinted in lower-level (spinal or muscular) pathways? Certainly some of the political speeches this season are executed without recruiting any brain activity whatsoever.

          • Sky Kerzner

            I imagine that they all coordinate to contribute to high-precision movements at various levels. The fingers in particular do have neuron bodies sitting in the brain whose axons control them directly, but certainly computations in tight, extra-cerebral feedback pathways involving sensory nerves and muscles allow for live fine-tuning. Some indirect evidence for this lies in the difficulty that the field of robotics has had in generating responsive fine-tuned actions without sensory neurons — they seem to be a crucial missing piece of robots, and so probably play a crucial role in humans.

            As for the political comment, that seemed extremely tangential and quite a stretch to fit in to the conversation, lol, but I understand the desire to bring it up — we all know its an ugly mess.

          • bensabio

            I can always find a way to fit some humor into a conversation, however tangential or stretched! In this case, couldn’t resist making the comment.

  • bensabio

    This is a most disappointing and uninformative article! Or else the research itself doesn’t deliver on the premise of the article. The only sentence that purports to address the subject is: “Essentially, our fingertip neurons, in a similar fashion as brain
    neurons, created a code that conveyed information about an edge’s shape.” But isn’t that “code…conveyed” to the brain? Presumably, if the research points to some new findings, some kind of integration and resulting behavior results before the impulses ever get to the brain (much as our reflex response to pain, I imagine.). But what is done with that coded information before it gets to the brain, and how does it lead to behavior that is not brain-mediated? Nothing is mentioned about this at all, yet that would be the point of the research (beyond just recording the
    “coded” impulses). I’d really like to know more about this interesting subject!

    • Ismaïl Ajíbølå Abdus-Salam

      You certainly are a neuropharmacologist. I also scanned the page for similar bits of info, but then, I realized this is not a specialist article.

      • bensabio

        I’m certainly not a neuropharmacologist, but just a regular old biologist who knows a little about neuroanatomy and physiology. The article should have followed through on its promise, whether written for specialist or for an intelligent, educated layperson..

    • Darxe

      i believe the article was misgiving too, as i wished for more detailed information as well, however, the article did follow through on the subject it was supposed to. “Your Fingertips Perform Brain-like Calculations” is the title and presumed subject of the article, and while not giving a font of information, it did indeed *cover* this, albeit, not well. the little bit of detail it did give to cover this subject were in the brief moments it talked about the fingertip neurons turning the information into a “code” of course, this code is sent to the brain for further processing, but the initial processing is the “brain like calculations”

  • kmtominey44

    Maybe thats how even dinosauers managed as well as they did.

  • michael scott

    This article sounds very interesting, but I don’t see how neurons in your fingertips can take the place of your brain. Your fingertips don’t think, and cannot interpret things and understand them because they’re not brains. Without the brain, fingertips are useless. No one can interpret the shape or feeling of something they touch without their brain being involved. It’s your brain that thinks, feels, and interprets what you touch with your fingertips, and it’s what controls your bodily functions. Without your brain you can’t make decisions, nor can you interpret things in your environment. Your brain is the headquarters of all your senses. Fingertips don’t have brains in them.

    • bensabio

      Lots of behavior is integrated without brain involvement at all! Most famously, the spinal reflexes (e.g., patellar reflex, withdrawal reflex, etc.) and there are lots of behaviors in the digestive tract that are coordinated locally with no brain involvement. The brain integrates and coordinates a lot of behavior, and of course is the seat of consciousness, but that’s not the whole story of the body’s behavior, not by a long shot!

      • michael scott

        I wrote a
        response to you yesterday, and I don’t see it here. I’m not a science genius,
        but what you’re saying about the brain having no involvement at all makes
        absolutely no sense to me. A body cannot function in any way without the brain,
        unless the body is hooked up to a life support machine, which is the only way a
        body can function without any involvement from the brain. You seem like you’re
        angry at my opinion, since you use an exclamation point at the end of your
        opening and closing sentences. There’s no need for you to get upset because I
        have a different belief and opinion than you do. This isn’t a contest. You and
        I don’t know how many things we believe in right now that we think are right,
        but could find out that we’re wrong about in the future. Whenever GOD reveals to me
        that something I believe is wrong, I correct myself and no longer believe the
        lie and accept the truth. I pray that you are the same way.

        • Darxe

          dude, he did not say that the body can function without a brain, but simply that some bodily functions are automatic actions, or do not involve the brain, as he said, reflex actions do not actually involve the brain at all (or atleast, tactile reflex actions, if you get cut, the neuron fires, reaches the spinal cord, and the spinal cord fires an impulse back telling the body part to move away from the direction of the cut. this all happens before the initial impulse reaches the brain, or while the initial impulse is getting processed.)

          Also, as far as i can tell, the exclamation points are simply a “tell” of excitement, or an eagerness to impart knowledge

          • michael scott

            If you believe that there are automatic functions that don’t involve the brain, that’s you’re right to believe that. I don’t believe that, but I might be wrong. It doesn’t make sense to me that something in one’s body can function without the brain being involved. Whether or not my opinion is absolutely true or not isn’t necessary for my salvation. From what I know so far, (other than a life support machine being involved) I believe that the brain must be involved in any bodily function somehow, some way, in order for that function to be possible. If I ever find out that I’m wrong about this, that’s ok, because discovering the truth about something is always a great experience, even though finding out you’re wrong can sometimes hurt, depending on what you’re wrong about. I’d rather know I was wrong about something so I can correct myself, than to remain wrong and ignorant. I don’t view the exclamation points the way that you do; I didn’t use any exclamation points when expressing the knowledge I had to share in my comments. Even so, you, Ben and I, all had some interesting comments about this subject, regardless of differences of opinion.

  • Phil

    “Meissner corpuscles react to light…”, so does that mean light levels affect how our fingertips process stimuli?

    • Carlos Gomez

      The sentence was “Meissner corpuscles react to light, fast deformations across the skin”. The comma is used to separate two adjectives being used (light, as in not heavy, and fast).

  • nomi

    Transformation from physical to electrical with different intensities and frequencies is a basic function of all sensory organs. It is very evident in eyes and ears. For touch may be we need to look more closely into the touch neurons rather then terming fingers sensors as brain. These different touch sensations get transmitted to brain and its brain who will make sense of what it is that we have touched consulting the memory.

NEW ON DISCOVER
OPEN
CITIZEN SCIENCE
ADVERTISEMENT

D-brief

Briefing you on the must-know news and trending topics in science and technology today.
ADVERTISEMENT

See More

ADVERTISEMENT

Discover's Newsletter

Sign up to get the latest science news delivered weekly right to your inbox!

Collapse bottom bar
+