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Gut-Brain Connection Could Lead To a 'New Sense' (newatlas.com)

A new study has revealed a "fast-acting neural circuit allowing gut cells to communicate with the brain in just seconds," reports New Atlas. Diego Bohorquez, senior author of the study, says "these findings are going to be the biological basis of a new sense. One that serves as the entry point for how the brain knows when the stomach is full of food and calories." He says it "brings legitimacy to [the] idea of the 'gut feeling' as a sixth sense." The study has been published in the journal Science. From the report: Remarkable new work from a team of researchers at Duke University has now revealed a previously unknown direct circuit between the gut and the brain that could allow for fast sensory communication that doesn't relay on laborious hormonal signaling. The research began with a big discovery in 2015 revealing that enteroendocrine cells, the cells in our gut thought to be the primary sensory receptor that communicate with the brain, actually contained nerve endings that seemed like they could directly synaptically communicate with vagal neurons and subsequently, the brain.

The new study first revealed that direct, and near instant, communication occurred between the gut and brain. A mouse was administered with a rabies virus that had been engineered with a green fluorescent tag. Tracing the signal of communication as the gut informed the brain of this virus revealed an immediate response in the vagus nerve. In under 100 milliseconds a single signal was seen to travel from the gut to the brainstem. In order to understand this new neural circuit, the team grew enteroendocrine cells in a lab dish alongside vagal nerve neurons. Not only did these two elements rapidly demonstrate communication, but it was discovered that glutamate, a foundational neurotransmitter, modulated the rate of transmission. What this experiment impressively revealed was that enteroendocrine cells don't solely signal to the brain via hormonal triggers, but also can directly communicate via neural synapses.

91 comments

  1. Movie quote by Anonymous Coward · · Score: 1, Funny

    Well my gut has shit for brains.

    1. Re:Movie quote by michelcolman · · Score: 1

      You've got to love the PR spin they put on this.

      The gut communicates with the brain, boring... wait, what if we tie it to the totally unrelated "gut feeling"? Yeah, good idea, that will get us the headlines. O, and mention a sixth sense! Great, that's a front page right there!

      While all they really discovered, is that our gut has the capacity to send a message to the brain when some kind of trouble happens inside the gut. They certainly did not discover any capacity of a police detective's gut to determine who killed a murder victim.

    2. Re: Movie quote by Anonymous Coward · · Score: 0

      Also, the retarded summary refers to a "circuit." This is retarded drivel. Since we are talking SENSES and not anything like MOTOR CONTROL, the retard got it wrong. Slashdot sucks.

    3. Re:Movie quote by mspohr · · Score: 1

      When I have to shit, my gut has no problem communicating with my brain. Who are these geniuses?

      --
      I don't read your sig. Why are you reading mine?
  2. The brain manipulates the body by davide+marney · · Score: 2

    "Scientists talk about appetite in terms of minutes to hours. Here we are talking about seconds," says Diego Bohórquez, senior author of the study. "That has profound implications for our understanding of appetite. Many of the appetite suppressants that have been developed target slow-acting hormones, not fast-acting synapses. And that's probably why most of them have failed."

    It also has profound implications regarding the manipulation of appetite by the brain.

    --
    "We receive as friendly that which agrees with, we resist with dislike that which opposes us" - Faraday
    1. Re:The brain manipulates the body by chthon · · Score: 1

      Or the manipulation of appetite by the gut?

    2. Re:The brain manipulates the body by Anonymous Coward · · Score: 0

      Would have thought something like this was already known? How on earth do kids pass science today with no basic understanding of human biology. Next thing you know there will be a "study" on how the gut can be influenced externally. It's one weird association people can have with others including animals... A mother can feel but no understand why a child has a sore stomach.

    3. Re:The brain manipulates the body by sheramil · · Score: 1

      Or the manipulation of appetite by bacteria living in the gut?

      Not you, Helicobacter Pylori. Nobody likes you.

    4. Re:The brain manipulates the body by Anonymous Coward · · Score: 0

      gut instinct?

      ~ ZsaZsaEuroglam

    5. Re:The brain manipulates the body by dfghjk · · Score: 1

      Only if you believe that appetite is something manipulatable by the brain. We know it doesn't work that way and, furthermore, what's being talked about is how things work, not discovering new things we didn't know we could do.

      We know that we can't simply manipulate hunger by thinking but, rather, it's the other way around, that hunger manipulates our thinking. This information doesn't have "profound implications" on what we already know doesn't happen, it suggests how something we know happens works.

    6. Re: The brain manipulates the body by Vintermann · · Score: 1

      Will people line up for a biohack that makes you seriously nauseous if you eat too much?

      Never mind that it's probably what this sensory pathway is for in the first place.

      --
      xkcd is not in the sudoers file. This incident will be reported.
    7. Re:The brain manipulates the body by nospam007 · · Score: 1

      "Or the manipulation of appetite by the gut?"

      Not only that. If you shit your pants, this 'circuit' immediately tells your brain.

    8. Re: The brain manipulates the body by Anonymous Coward · · Score: 0

      That's obviously false. Anyone who has ever engages in an all day game session has probably gone ten hours without even thinking of food, only to recognize they are "starving" once the game is over.

      Fat people tend not to be happy not have active hobbies. People often overeat out of boredom, which is a symptom of unhappiness, which is itself a symptom of not being fulfilled in life in one aspect or another. Sort of like posting on Slashdot.

  3. Gutman by Daralantan · · Score: 1

    My gut sense is tingling!

    1. Re:Gutman by Opportunist · · Score: 1

      Oh yes please, an overweight superhero is pretty much all that's missing from the fold.

      --
      We used to have a Bill of Rights. Now, with the rights gone, all we have left is the bill.
    2. Re:Gutman by Anonymous Coward · · Score: 0

      No. Wait. It was just that egg salad sandwich from the vending machine.

    3. Re:Gutman by Daralantan · · Score: 1

      This does remind me of some video game communities being really mad that there weren't more fat action hero characters.

    4. Re:Gutman by Opportunist · · Score: 1

      I have no idea why I have to think of the Simpsons episode where Homer gets stuck with his lower half in the tank full of radioactive fumes and Bart says "For once, Homer's fat ass has prevented the release of toxic gas".

      --
      We used to have a Bill of Rights. Now, with the rights gone, all we have left is the bill.
  4. Has the study been replicated? by philipkd · · Score: 4, Insightful

    I want to propagate a meme whereby any time a "new study" is cited, we ask reflexively, "has it been replicated?" Doing so seems to be the only way out of the replication crisis. We, as consumers of pop science, need to demand it.

    1. Re:Has the study been replicated? by Anonymous Coward · · Score: 1

      What about this new study that found there is no need for replication?

    2. Re:Has the study been replicated? by philipkd · · Score: 1

      We need to replicate the idea that we have a new sense, as opposed to a fast-acting hormonal response. One replication of this study could bring more clarity to the subject. Otherwise, in three years, it may fail replication but the gut-brain connection idea could have already gone viral by then, appearing in dumb TED talks, and spawning all sorts of pop psychobabble books.

    3. Re:Has the study been replicated? by sjbe · · Score: 1

      What about this new study that found there is no need for replication?

      Has it been replicated?

    4. Re:Has the study been replicated? by Anonymous Coward · · Score: 0

      Headline should read:

      Gut-Brain Connection Could Lead To a Nuisance

    5. Re:Has the study been replicated? by Anonymous Coward · · Score: 0

      Then surely we should also equally reject all past studies that have not been replicated as well?

    6. Re: Has the study been replicated? by Anonymous Coward · · Score: 0

      There is no crisis. We, as consumers, just need to accept the fact that "new" research is like, 50/50

    7. Re: Has the study been replicated? by Anonymous Coward · · Score: 0

      You can say that again!!

    8. Re: Has the study been replicated? by bobmagicii · · Score: 1

      "in just seconds" bitch please thats slower than my first dialup internet i was playing quake in a mere 400ms.

  5. not surprising by sad_ · · Score: 2, Interesting

    the gut being one of the greatest entry points into the body, it should have a fast connection to the brain in case something is not right that a conter-reaction is issues right away.

    --
    On a long enough timeline, the survival rate for everyone drops to zero.
    1. Re:not surprising by Anonymous Coward · · Score: 0

      Not surprising at all since the stomach can react poorly to SSRIs since it has nerve cells.

  6. seeing j public being hoodwinked bushwhacked.. by Anonymous Coward · · Score: 0

    makes me feel like puking.. cease fire stand down.. there are moms & babys in every town.. conspire to occupy the truth.. thanks..

  7. glutamate, a foundational neurotransmitter by Anonymous Coward · · Score: 0

    it was discovered that glutamate, a foundational neurotransmitter, modulated the rate of transmission.

    Well, that explains why you're hungry again 1/2 an hour after eating Chinese food.

    All that monosodium glutamate messes your sixth "hunger sense" up.

    1. Re:glutamate, a foundational neurotransmitter by Anonymous Coward · · Score: 5, Interesting

      This has been settled science for years. That glutamate affects the sensory response of the stomach to the introduction of food is not new.

      High levels of glutamate in your food will make you feel full faster, causing you to eat less. You're hungry again 1/2 hour later because glutamate dissipates from the body quickly taking the sense of satiety with it.

      This is why almost all chinese restaurants are buffet format. Patrons eat less because of all of the MSG.

    2. Re:glutamate, a foundational neurotransmitter by Anonymous Coward · · Score: 0

      This has been settled science for years. That glutamate affects the sensory response of the stomach to the introduction of food is not new.

      High levels of glutamate in your food will make you feel full faster, causing you to eat less. You're hungry again 1/2 hour later because glutamate dissipates from the body quickly taking the sense of satiety with it.

      This is why almost all chinese restaurants are buffet format. Patrons eat less because of all of the MSG.

      Well, damn.

      I tried to crack a joke and stumbled on the truth.

    3. Re: glutamate, a foundational neurotransmitter by Anonymous Coward · · Score: 0

      no, you cracked a joke and ran into pseudoscientific wittering tinged with yellow peril racial conspiracy hysteria

    4. Re:glutamate, a foundational neurotransmitter by Anonymous Coward · · Score: 0

      You need to eat in a better class of Chinese restaurant. One that doesn't cater to Westerners.

    5. Re:glutamate, a foundational neurotransmitter by Anonymous Coward · · Score: 0

      This is why almost all chinese restaurants are buffet format. Patrons eat less because of all of the MSG.

      No, it's because it's much cheaper to cook a massive vat of a dish and then leave it on a table festering for 10 hours than to cook individual portions. Better (but pricier) restaurants don't do buffet.

    6. Re:glutamate, a foundational neurotransmitter by schweini · · Score: 1

      This might be interesting, because, IIRC, Glutamate correlates to the Umami flavour, which is supposed to be savoury-meaty, which in turn would imply probable presence of Proteins, which in turn take longer to digest. So it would make sense that Glutamate sends a signal to the brain saying that the contents might not feel like much, but are good enough to stop eating?

  8. Taco Bell run time measured by Anonymous Coward · · Score: 0

    "The new study first revealed that direct, and near instant, communication occurred between the gut and brain. ...
    In under 100 milliseconds a single signal was seen to travel from the gut to the brainstem."

    Duh. A new study, really?

    I think we've all experienced the "instant" less than 100ms speed at which a Taco Bell value meal will make you run for the bathroom, assuming you can even make it.

  9. Well... by jawtheshark · · Score: 1

    I think my gut is full of shit....

    --
    Ahhh...the great dumpster continuum. Many a free computer will be found there. -- sowth (748135)
  10. Re:In support of mods in comments by Anonymous Coward · · Score: 0

    fuck off ivan

  11. i may have a little pee on my brain.. by Anonymous Coward · · Score: 0

    but my gut tells me there's better days ahead after the spiritual bankruptcy proceedings proceed..

  12. Gut Feeling by Anonymous Coward · · Score: 0

    Something 'bout the way you taste makes me want to clear my throat

  13. 6th by markdavis · · Score: 4, Insightful

    >"He says it "brings legitimacy to [the] idea of the 'gut feeling' as a sixth sense."

    More like the 12th or 16th "sense". I wish the whole "5 senses" thing from thousands of years ago would die already. I mean, anyone who doesn't immediately recognize a sense of balance or temperature or body position (or many others) as a "sense" doesn't understand the concept of sensing the world around them.

    https://en.wikipedia.org/wiki/...

    1. Re:6th by Anonymous Coward · · Score: 0

      I'd also like to know how it possibly lends any legitimacy to a "gut feeling" being an actual sense. Nobody uses the term "gut feeling" to refer to them sensing they are full/hungry/nauseated or anything like that, but for things their gut couldn't possibly sense.

    2. Re:6th by Anonymous Coward · · Score: 0

      Addendum:

      This is because a unit is an entirely abstract concept when applied to reality on the "meta" scale we humans observe on a regular basis.

      It is important to remember that and that it is not possible to mix concrete discrete assertions with such an abstraction.

      So the objection to "five senses" is nothing more than an objection to the fact the line between these distinct domains has been crossed.

      There certainly are "five senses" as a subset of any number of senses. An individual "sense" unit may be composed of an arbitrary number of sub-units.

      This is abstraction.

    3. Re:6th by skids · · Score: 2

      I wish the whole "5 senses" thing from thousands of years ago would die already.

      Yeah how many 6th senses does that make now?

      Were I a film school student, I'd make a short featuring of a civilization of people dragging themselves around using walkers and clinging to handrails, with a "superhero" that had a 6th sense... he calls it "balance"... which allows him to do superhuman feats like walking.

      Make it funny enough and maybe it would kill the 6th sense meme.

    4. Re:6th by Anonymous Coward · · Score: 0

      You are exactly right. The summary is stupid, written by and for uneducated people.

    5. Re:6th by reboot246 · · Score: 1

      Yeah, not to mention those of us who have synesthesia!

      Look that one up if you have to.

  14. Spider man by Oswald+McWeany · · Score: 1

    So is the true source of Spiderman's spidey-sense the huntsman spider he stuck up his butt?

    --
    "That's the way to do it" - Punch
  15. i have a gut feeling... by Anonymous Coward · · Score: 0

    ..that this is not true... oh wait!

  16. The brain doesn't need to manipulate appetite by Viol8 · · Score: 2

    It generates it in the first place and in theory could modify it anyway it sees fit. The digestive system doesn't understand appetite - it just understands full, processing, empty and poison. Anything more than that is qualia generated by the brain.

    1. Re:The brain doesn't need to manipulate appetite by dfghjk · · Score: 1

      Correct, although appetite is a primitive function in the brain, so it's misleading to suggest the brain can "modify it anyway it sees fit" and we know it can't since we'd have far fewer overweight people. Appetite is a function of the brain itself, the brain doesn't need to manipulate the gut in order to influence it.

    2. Re:The brain doesn't need to manipulate appetite by dj245 · · Score: 1

      It generates it in the first place and in theory could modify it anyway it sees fit. The digestive system doesn't understand appetite - it just understands full, processing, empty and poison. Anything more than that is qualia generated by the brain.

      The vagus nerve is a huge and largely unexplored area of study. We now understand the digestive system to be much more complex and important than simply a system which turns starches, proteins, and sugars into usable matter for the rest of the body. The headline is stupid but there is a lot of new research that vagus nerve communication is 2-way, and fiddling with it can modify the behavior of the brain.

      --
      Even those who arrange and design shrubberies are under considerable economic stress at this period in history.
    3. Re:The brain doesn't need to manipulate appetite by Viol8 · · Score: 1

      Fiddling with the optic nerve would modify the behaviour of the brain. That doesn't mean what we describe as vision is done in the eye.

  17. No, it does not. by QuietLagoon · · Score: 1

    He says it "brings legitimacy to [the] idea of the 'gut feeling' as a sixth sense."

    "Gut feeling" and "sixth sense" have nothing to do with physical feelings within the gut. They are more of an intuition type of thing regarding the environment outside the body, not in the abdomen. Geesh.

  18. %d by Anonymous Coward · · Score: 0

    %d

  19. I don't overeat... by Anonymous Coward · · Score: 0

    ...I'm just laggy

  20. 6th Sense by billybob2001 · · Score: 3, Funny

    He says it "brings legitimacy to [the] idea of the 'gut feeling' as a sixth sense."

    Gut 6th sense? I see bread, people.

    1. Re:6th Sense by SCVonSteroids · · Score: 1

      Plot twist:

      YOU are actually a loaf!

      --
      I tend to rant.
    2. Re:6th Sense by billybob2001 · · Score: 1

      Plot twist:
      YOU are actually a loaf!

      *SPOILER*
      I thought I was aloaf, but it turns out I was brown bread all along.

  21. Glutamate again by Anonymous Coward · · Score: 0

    >...it was discovered that glutamate, a foundational neurotransmitter, modulated the rate of transmission.

    Possible tie in with MSG headaches? (Wikipedia says double-blind experiments have failed to find a link between MSG and headache's, but I experience the headaches when not expecting them, only to later determine that something I ate a few hours before did in fact contain MSG.)

    1. Re:Glutamate again by Oswald+McWeany · · Score: 1

      >...it was discovered that glutamate, a foundational neurotransmitter, modulated the rate of transmission.

      Possible tie in with MSG headaches? (Wikipedia says double-blind experiments have failed to find a link between MSG and headache's, but I experience the headaches when not expecting them, only to later determine that something I ate a few hours before did in fact contain MSG.)

      I think the problems saying MSG aren't linked to headaches is that- quite likely MSG by itself is not responsible for headaches. MSG combined with lots of salt and oil (as is common in Americanised versions of Asian foods) causes headaches. The combination of those three ingredients in high doses is what causes the problem. Way too many people have "Chinese food" reactions for it to be all in the head. I know I always feel crappy after eating Ameicanized Chinese food but I think it's more a combination of things, salt- fat AND MSG. Salt and fat are combined in lots of food- and MSG is added to other foods without causing problems. I think when you OD on all three- that's when you get the "MSG Reaction".

      --
      "That's the way to do it" - Punch
    2. Re:Glutamate again by Anonymous Coward · · Score: 0

      How's your blood pressure? I found out mine was very high having experienced a lot of headaches in recent years, and the doc put me on a low-sodium diet. Results include far fewer headaches.

      And of course, the "S" in "MSG" stands for "sodium."

    3. Re:Glutamate again by Anonymous Coward · · Score: 0

      This sounds more like symptoms of high blood glucose.

      American "Chinese" food contains significant amounts of sugars and carbohydrates which are digested very quickly and in such quantities as you may observe in plum sauce for example could easily produce a heightened blood glucose capable of producing such symptoms.

      The association with MSG is an example of "correlation does not imply causation" and simple confirmation bias.

  22. TL;DR: by NicknameUnavailable · · Score: 1

    People who rely on their "gut feeling" can't distinguish between skipping lunch and a legitimate reason to feel uncomfortable with a situation.

  23. That's great and all, but ... by drew_kime · · Score: 1

    One that serves as the entry point for how the brain knows when the stomach is full of food and calories.

    Your stomach can't be full of calories. That's like saying it's full of ounces, or full of liters. It's a unit of measure.

    Excuse me while I go yell at clouds.

    --
    Nope, no sig
  24. We are the computer by dr.Flake · · Score: 1

    It all becomes clear now.
    And Douglas Adams was so close.
    But it's not the mice controlling our lives, it's the microbes!!

    Tilting outcomes in petridishes all over the world, steering our emotions and hunger.

    We are being scrutinised i'm telling you, like someone with a microscope studies creatures that swarm and multiply in a drop of water. Oh the irony!

    Our gut has a mind immeasurably superior to ours and regard this earth with envious eyes and they slowly and surely are drawing their plans against us!

    cue music......

    --
    Why are other peoples sig's always more witty ???
  25. Bulveristic category drift by epine · · Score: 1

    The method of Bulverism is to "assume that your opponent is wrong, and explain his error."

    This is easily accomplished by misconstruing the original frame. Unless you have an intellectual conscience.

    The original five senses were all exo-perceptual.

      This was back when no other category had been explicated in specific terms (the ancient Greeks were no dummies and surely suspected interior sensation).

    Wikipedia doesn't add a "(film)" clause to movie titles, unless the title already has an established meaning (such as the book upon which the movie was based). But then more pages are added, and sometimes that old film without "(film)" has "(film)" added in retrospect (or eventually "(1998 film)" added in retrospect).

    Note that "sixth sense" in its early meanings was usually exo-perceptive: eerie emanations of metaphysical misalignment in the world around you.

    Humans don't seem to have magnetic perception. The melanopsin sensors in the retina can't be classified as "vision". However, "sight" is almost viable, so I'm not quick to add this as an entirely separate item.

    So what other exo-perceptions might we now add to the archaic list? We've already got the skin, eyes, ears, mouth, and nose on the list. That's the majority of the human periphery. The anus can discriminate gas, liquid, solid. But it's hardly exo unless you're badly prolapsed (I mean your anus, not your argument).

    Within its pre-existing category, I really don't think the original five was totally off base.

    1. Re:Bulveristic category drift by epine · · Score: 1

      PS: I guess I would have to accept visceral reference-frame cottonmouth (the roller-coaster stomach-in-mouth thing) as a unique exo-perceptive sense outside the original five.

      But only since Einstein.

    2. Re:Bulveristic category drift by markdavis · · Score: 1

      >"So what other exo-perceptions might we now add to the archaic list? We've already got the skin, eyes, ears, mouth, and nose on the list. That's the majority of the human periphery. Within its pre-existing category, I really don't think the original five was totally off base."

      That depends on your meaning of "exo-perceptions". If you just mean sensing things outside of the body (things that other people can also sense that you sense), the colloquial "5 senses" is still very wrong. Temperature is external to the body, that is sensed almost immediately (skin is not the sense, the sense is classically "touch" and "touch" describes pressure on the skin, not temperature). Balance is external to the body (it is gravity and acceleration), both are sensed... and by a unique, separate organ (the vestibular system). So there are at least 7 "exo" senses (if you include taste- something that isn't quite "exo" :) ).

  26. Biggest ever, believe me by Tablizer · · Score: 1

    I have an Einsteinien gut.

  27. Brave folks by The+Snazster · · Score: 1

    Doing this research must have required a lot of intestinal fortitude.

  28. Re:In support of mods in comments by Anonymous Coward · · Score: 0

    Shut up n1gger.

  29. I knew it! by Anonymous Coward · · Score: 0

    I had a feeling about this.

  30. What a missed comedic opportunity.... by chaboud · · Score: 1

    This would have played so well into "The Colbert Report" for coverage, it's sad to not have the chance.

  31. Huh? by SCVonSteroids · · Score: 2

    A new study has revealed a "fast-acting neural circuit allowing gut cells to communicate with the brain in just seconds,"

    That's.... not very fast.

    --
    I tend to rant.
  32. ignore your gut reactions by Anonymous Coward · · Score: 0

    and you will live to regret it. I have examples of this throughout my life, from the time I was a small child. When people say they have a 'gut feeling', they know they are receiving a warning from senses that we all have but are taught to dismiss, ignore and override.

  33. Non ethical by Anonymous Coward · · Score: 0

    How can you give a mouse rabies and doom it? Your science isnâ(TM)t more important than another life. Disgusting

  34. There is some preprocessing by lamer01 · · Score: 1

    that takes place before the signals reach the brain so yeah.

    1. Re:There is some preprocessing by Viol8 · · Score: 1

      Preprocessing is not the same as recognition.

  35. Sadly, replication does not matter... by Anonymous Coward · · Score: 0

    Because unless YOU PERSONALLY have replicated it, the ones replicating it do not have any more credibility than the ones doing it the first time.
    (Hint: Argument from popularity is a [very popular] logical fallacy.)

    It's the same problem as "Who watches the watchmen?". And the answer is also the same: In the end, it is always you, who's the only one, who can finally judge it for yourself. Everything else by definition requires blind trust in somebody else.

    And in any case, if you only read a study, even one with loads of peer review, then all YOU have of it, is anecdotal evidence. (Just like you only have anecdotal evidence of the existence of this comment... or most of the things in your daily life.)
    I'm not saying that that is such a bad thing. I mean you don't jump off a high-rise to check if one dies from it. You haven't even seen anyone do it. So you do not even have anecdotal evidence. Yet you trust it to be true. ... That is OK.

    I guess I just want to say that this rabbit hole goes soo much deeper than the the point you made. Please think this through to the end, and let's not waste time on silly pseudo-educated popular science/philosophy discussions that have been answered millennia ago.

    1. Re: Sadly, replication does not matter... by Anonymous Coward · · Score: 0

      No, u

  36. Signal for the brain by philmarcracken · · Score: 1

    >One that serves as the entry point for how the brain knows when the stomach is full of food and calories. I already have an organ I use to determine how many calories I need, my brain. The people too lazy to look up their TDEE and count are either perfectly happy being under/overweight or are delusional about food energy and thermodynamics.

  37. Gut Feeling by Anonymous Coward · · Score: 0

    I'll just leave this here...

    Gut Feeling

    I am your DJ.