History Main / CentipedesDilemma

* In one ''ComicBook/ArchieComics'' story, Jughead beats Reggie at bowling by tricking him into actually focusing on the mechanics of play (e.g. how many steps he takes during windup, the ergonomics of the bowling ball) instead of just playing.
* In ''ComicBook/CerebusTheAardvark'', the title aardvark tries to win a ball game using this trope, asking if he breathes in or out when tossing the ball. Cut to panel of his panicked partner contemplating it. Cut to panel showing said partner [[SubvertedTrope having won]] and saying, "I breathe out!"
* In an ''ComicBook/TheInferiorFive'' comic that parodied the ''Franchise/XMen'', the equivalent of [[WingedHumanoid Archangel]] is shown wearing a sweater. Naturally, one of the Five asks him how he puts on a sweater over his wings. The poor mutant loses it because, now that he's thought about it, he'll never be able to do it again.
* In one ''Franchise/{{Tintin}}'' story, ''[[Recap/TintinTheRedSeaSharks The Red Sea Sharks]]'', Captain Haddock is unable to sleep after Allan mockingly asks him if he sleeps with his beard under or above the covers. This ends up saving his life and those of [[NiceJobFixingItVillain everyone on the ship.]] (Captain Haddock is shown to sleep on his stomach in ''Tintin and the Picaros''.)
* ''Franchise/WonderWoman'':

Compare with AchievementsInIgnorance; ActingUnnatural, DamnYouMuscleMemory, DontThinkFeel, MagnumOpusDissonance, ParalysisByAnalysis, PerformanceAnxiety, PuffOfLogic, YouWereTryingTooHard, ThoughtAversionFailure, ReminderOfImpossibility, and ThereIsNoTry. DontLookDown can result in this, if the person was doing fine beforehand and being told not to look down causes them to look.

Compare with AchievementsInIgnorance; ActingUnnatural; DamnYouMuscleMemory; DontThinkFeel; MagnumOpusDissonance; ParalysisByAnalysis; PerformanceAnxiety; PuffOfLogic; YouWereTryingTooHard; ThoughtAversionFailure; ReminderOfImpossibility; and ThereIsNoTry. Contrast AutopilotArtistry.

** In ''All-Stars 3'', Kennedy Davenport had previously made a name for herself in Season 7 as the best dancer in the cast. Come ''All-Stars 3'', the queens had to imitate various pop divas for a challenge and Kennedy is assigned Music/JanetJackson for seemingly-obvious reasons. However, Kennedy struggles with the challenge and admits that she's more used to dancing off-the-cuff rather than following a choreographed routine.

** Season 5 contestant Alyssa Edwards became a fan-favorite due to her campy, LargeHam personality making her a FountainOfMemes. But whenever she's ''told'' to be funny for a comedy challenge, she gets stuck in her head, which ultimately leads to her elimination.
** In ''All-Stars 3'', Kennedy Davenport had previously made a name for herself in Season 7 as the best dancer in the cast. Come ''All-Stars 3'', the queens had to imitate various pop divas for a challenge and Kennedy is assigned Music/JanetJackson for seemingly-obvious reasons. However, Kennedy struggles with the challenge because she's more used to dancing off-the-cuff rather than following a choreographed routine.

** Season 5 contestant Alyssa Edwards became a fan-favorite due to her campy, LargeHam personality making her a FountainOfMemes. But that was just her being herself; whenever she's ''told'' to be funny for a comedy challenge, she would get stuck in her head, which ultimately leads to her elimination.
** In ''All-Stars 3'', Kennedy Davenport had previously made a name for herself in Season 7 as the best dancer in the cast. Come ''All-Stars 3'', the queens had to imitate various pop divas for a challenge and Kennedy is assigned Music/JanetJackson for seemingly-obvious reasons. However, Kennedy struggles with the challenge because most of her dancing is off-the-cuff, rather than following a choreographed routine.

* ''Series/RuPaulsDragRace:
** Season 5 contestant Alyssa Edwards became a fan-favorite due to her campy, LargeHam personality making her a FountainOfMemes. But whenever she's ''told'' to be funny for a comedy challenge, she gets stuck in her head and flounders, which ultimately leads to her elimination.
** In ''All-Stars 3'', Kennedy Davenport had previously made a name for herself in Season 7 as the best dancer in the cast. Come ''All-Stars 3'', the queens had to imitate various pop divas for a challenge and Kennedy is assigned Music/JanetJackson for seemingly-obvious reasons. However, Kennedy struggles with the challenge because most of her dancing is off-the-cuff rather than following a choreographed routine.

** In ''All-Stars 3'', Kennedy Davenport had previously made a name for herself in Season 7 as the best dancer in the cast. Come ''All-Stars 3'', the queens had to imitate various pop divas for a challenge and Kennedy was assigned Music/JanetJackson for seemingly-obvious reasons. However, Kennedy admitted that most of her dancing is off-the-cuff, and following a choreographed routine is not her strong suit.

* ''WesternAnimation/BobsBurgers'': In "The Fresh Princ-ipal", Teddy begins asking Bob how he is able to flip burgers so well, causing Bob to immediately screw up once he starts thinking about it.

If this is attempted on a group of people simultaneously, it may lead into someone biting into the AppleOfDiscord.

* ''Wiki/SCPFoundation'': SCP #1475 is a person who created and took a drug that allows him to use [[NinetyPercentOfYourBrain 100% of his brain]], giving him complete control over his body to the point where he made his brain rewire itself to [[TheSleepless remove the need for sleep]]. The downside? Everything his body ''used'' to do automatically, he now has to do manually, such has pumping blood through his veins or digesting food. [[BlessedWithSuck This takes so much of his concentration that he's left bedridden and unable to move]].

** BulletHell shooters and [[TheTetrisEffect timed puzzle games]] can be the same way.

Compare with AchievementsInIgnorance; ActingUnnatural; DamnYouMuscleMemory; DontThinkFeel; MagnumOpusDissonance; ParalysisByAnalysis; PerformanceAnxiety; PuffOfLogic; YouWereTryingTooHard; ThoughtAversionFailure; ReminderOfImpossibility; and ThereIsNoTry.

* ''Manga/DetectiveConan'':

* In ''[[Fanfic/{{Eleutherophobia}} Lost World]]'', Tom narrates that he hates thinking about doing basic things such as talking and reading because he usually loses his ability to do them in the process, now that he has control of his body again.

* ''Literature/{{Deverry}}: Cullyn, acknowledged as the best swordsman in Deverry, is training Rhodry how to better his swordmanship, by going through the motions very, very slowly. Rhodry reflects on how hard it is to manage the sword properly when you have to think about each movement, rather than doing it instinctively -but he's also far more aware of how each step fits into the whole of using a sword.[[note]]Cullyn's daughter is able to beat men several years her senior in combat.[[/note]]

The trope is sufficiently well-known that sometimes the writer will just have someone comment, "Oh, he's got Centipede's Dilemma," or the like, rather than actually explaining what the problem is when Mr. Awesome starts messing up.

[[folder:Real Life]]
* In military, the Close Order Drill, "square bashing", originates in overcoming this issue. Making the movements automatic and instinct in the muscle memory creates the basis of action on battlefield.
** Learning "Drill and Ceremony" (D&C) in the military is an example. Teaching a soldier how to march makes them consciously think about how their arms and legs move during what is, essentially, "precision walking". Many recruits, when first instructed to swing the opposite arm forward with each step, overthink it so much that they will initially swing the arm of the ''same'' side with each step, resulting in a frankly hilarious and incredibly unnatural looking stride. It literally takes ''weeks'' to learn how to march to the proper cadence. Not to mention a multitude of other skills in the military, such as firing a weapon, or [[GunStripping disassembling and reassembling]] equipment for maintenance and/or repair. Particularly important if you need to fire, disassemble, and reassemble your weapon in the midst of combat (such as when needing to clear a misfire from your weapon). Also note that you may need to do this, and any other important tasks, while also dealing with the mother of all fight-or-flight-induced adrenaline surges.
** In the Finnish Army, the conscripts are taught first to disassemble and reassemble the service weapon normally, then behind one's back but eyes open, then blindfolded, and finally behind one's back and blindfolded (blindfolding one's eyes does affect muscle coordination and balance). The nimblest can perform it under 30 seconds with the RK 62 assault rifle.
* "Many things -- such as loving, going to sleep, or [[ActingUnnatural behaving unaffectedly]] -- are done worst when we try hardest to do them." -- Creator/CSLewis.
* As a general rule, any situation where a person's pulse needs to be taken is also a situation where breathing rate needs to be taken. Since breathing rate is under direct conscious control, the proper procedure is to count breaths and take the pulse simultaneously, and ''never'' mention breathing to avoid this trope. And now you know. Hey, [[TVTropesWillRuinYourLife we warned you.]] Somewhat related is [[http://en.wikipedia.org/wiki/White_coat_hypertension white coat hypertension,]] wherein some people's blood pressures elevate reflexively when intimidated by the idea of medical examinations.
* Riding a bike is probably the most famous example: practically everyone learns to ride a bicycle by having their instructor secretly let go of the handlebars so they'll continue riding along without thinking about it. If you try to worry about how the bike's staying upright, you're bound to lose your balance. Likewise, steering a two-wheeled vehicle requires briefly counter-steering (turning away from the intended direction) to get the bike to track into the turn. This is done automatically by new riders, but when trying to master leaning they often skip this step, keeping the bike from turning much no matter how much they lean.
** A phenomenal demonstration of this is the [[https://www.youtube.com/watch?v=MFzDaBzBlL0 'backwards bicycle']], originally created as a bit of a joke, which includes a gear between the fork and the handlebars that reverses the steering direction. I.e., turn the bars right to steer left and vice versa. It took a skilled bike rider ''months'' of daily practice to retrain his brain to operate it. Even better, this done, he then found himself unable to ride a normal bike. Though that came back after only a few minutes. Presumably if he kept switching back and forth he'd be fluently 'bilingual' with both bikes, able to ride either at will. Note that his young son, who was far less experienced at bike riding, picked it up much faster.
** Just try riding a tricycle after always having ridden a bicycle. You'd think if anything was going to overturn, it'd be the two-wheeler, not the inherently stable three-wheeler. Nope. You have to consciously turn the handlebar (and moderate your speed). Now imagine consciously turning a bike handlebar when riding. Some makers are starting to offer trikes that lean into bends to make the experience closer to that of a bike.
* Just about any time you realize you're performing a complex series of actions (e.g. a sequence of keystrokes) over and over again, you're likely to start thinking about how you're managing to do it so fast -- and immediately screw it up or have to slow down. Some people have reported typing quickly when they felt they were typing slowly, and upon realizing that they typed quickly, they either couldn't type quickly anymore or couldn't type both quickly and ''precisely'' anymore.
* Related to [[http://en.wikipedia.org/wiki/Unusual_software_bug#Schr.C3.B6dinbug schrödinbugs]]: a computer bug that seems to disappear or change when observed.
* Typing in general is like this. Anyone who can touch-type, or at least find their way around the keyboard with a decent degree of proficiency and speed, will 'know' how to find any given letter with their fingertips without looking at it or consciously even trying to locate it. ''Ask'' them where, say, the K key is, and they may well find it a whole heap harder.
* Anyone who's learned to [[DrivingStick drive stick shift]] after ''first'' learning to drive on an automatic knows this trope intimately. All the complicated motions and checking of gauges and looking around that have become instinct fall apart with the addition of just one more thing to do. Nothing you internalized involved moving your left foot or paying attention to the [=RPMs=], and that's enough. And people who drive stick and shift to automatics have to remember that they don't have to use their left foot. Also, the reason drivers from Britain to America, and similarly flipped countries, have trouble has less to do with switching sides and more relearning driving. Roundabouts for instance, making turns, even something like checking mirrors for traffic. Try parallel parking with a different side, or not punching a hole in the driver's door when you try to shift gear.
** It also works in reverse, when you start thinking about what to do with your (now unused) left foot, although it's more a case of DamnYouMuscleMemory.
* Pianist Glenn Gould said this about his piano playing.
* A mild version can be experienced by saying, reading, or thinking about a particular word too much (try all the uses of the word "pink" on the PinkProductPloy page for a good example). After a certain number of repetitions the word itself will lose all meaning to you. Your brain still consciously knows it's a symbol for something, and know what that something is, but it feels like you're no longer using a word, but rather a really weird symbol that means the same thing. It is called [[http://en.wikipedia.org/wiki/Semantic_satiation semantic satiation]].
* There is a ploy in American football called "freezing the kicker" or "icing the kicker" which relies on this trope. When one team is lining up to kick a field goal, normally accomplished within a set period of time while a play-clock is ticking down, the opposing coach calls a meaningless time-out ''just'' before the play is about to start, to stop the clock and give the placekicker a minute or two to overthink his kick. In some studies this has been [[http://en.wikipedia.org/wiki/Icing_the_kicker statistically shown to work]] on certain attempts, as kickers have a slightly lower success rate after being "frozen".
* [[http://www.sciencedaily.com/releases/2010/09/100925120110.htm This is a major factor]] in professional athletes "choking" generally, and in fact can cause them to do so ''more'' often than amateurs.
** On that note, Shaquille O'Neal's infamously poor free throw shooting. Throughout his career, Shaq was a decent-to-good free throw shooter ''in practice''; in a game situation, with nothing going on around him and everybody in the stadium looking right at him, however, he couldn't deliver.
** Also in basketball, the origin of the phrase "he was too open" when a player receives the ball with so much time to shoot before the defender arrives that he overthinks the shot and misses it.
** This is also why, in Major League Baseball, if the pitcher is throwing a no-hitter, it is considered ''EXTREMELY'' dickish to point it out to him in the middle of the game. Now he's going to be thinking about it, and will probably choke.
*** Though trying not to make the pitcher aware of the continuing no-hitter usually entails the pitcher's teammates avoiding him like the plague while in the dugout after the fifth inning or so. One has to imagine that sitting on the bench when not pitching, only to notice that everyone else is huddled at the other end of the dugout, would alert pitchers who weren't already aware than they had a no-no going. So in deliberately trying not to bring up the situation to the pitcher, [[MortonsFork his teammates probably made the pitcher very aware of the situation]].
** [[http://espn.go.com/golf/story/_/id/8865487/tiger-woods-reinvents-golf-swing-third-time-career-espn-magazine This]] ESPN the Magazine article discusses this in analyzing pro golfers who sought to improve their game by changing their swing. In almost every instance, a promising, skilled golfer lost every bit of promise and skill the second he took a look at his swing.
** An actual [[http://www.mayoclinic.org/diseases-conditions/yips/basics/definition/con-20031359 acknowledged medical condition known as "Yips"]], involuntary wrist spasms, is thought by some to be a form of this trope, and golfers are quite familiar with it since it tends to strike when they're trying to line up a putt. However, [[http://www.newyorker.com/magazine/2014/05/26/the-yips researchers suggest]] that it may be a neurological condition exacerbated by the performance anxiety common in sports.
** A technique in platform and springboard diving known as "Dumb Diving," wherein the diver clears their mind the moment before starting their dive, rather than focusing on each individual move in the dive.
* Sometimes people have this dilemma with sleeping. It happens when you're lying in bed, tired, but then you start thinking about sleep. Thus you become too conscious to relax. It'll happen sometimes when you need to be up earlier than usual the next day and try to force yourself into sleep. If you're told that you don't actually need to sleep, often you then fall asleep easily, as the stress and therefore the need to focus on the process is resolved.
** A similar issue arises for those who are sleepy at work. It's all too easy to fall asleep on the job after trying to fight it, risking a literal rude awakening by a supervisor at best and causing a major workplace accident at worst. But trying to take a deliberate nap during an hour-long lunch break precisely so that the former scenario doesn't happen? It's easier to climb Mt. Everest.
** Perhaps this is part of the criticism of sleep-tracking apps, devices, handwritten logs, and the like: they make you consciously think about the fact that you're going to sleep at a particular time and all the phases of them, resulting in a [[SelfInflictedHell self-inflicted]] form of the [[https://en.wikipedia.org/wiki/Hawthorne_effect Hawthorne effect]].
** This is one of the most difficult aspects of adapting to polyphasic sleeping, as the need to successfully fall asleep during extremely small windows of time knowing that you have to be up and moving again in 20 minutes is an easy thing to spend 20 minutes thinking about... but as soon as you're up and the pressure's off, the tiredness hits you. Luckily, after keeping this up for a couple weeks the process of napping at certain times becomes second nature and the pressure eases.
* In German primary schools, the kids sometimes have to take grammar tests that involve conjugating verbs in their own language. Usually, they're able to get the verb forms right in their sleep, but when they're explicitly asked to compose, let's say, the second-person singular form after being taught how it's assembled from a verb stem and a suffix, some suddenly get it wrong even though it's their own mother tongue. Might occur in other languages as well.
** For the same reason, foreign language classes now teach much less grammar than they used to -- knowing the grammar too well often left people stuck and unable to speak.
* The concept of "immersion" in fiction. Writers of [[{{Escapism}} escapist stories]] try their hardest not to draw their readers' attention to the fact they are reading a book, watching a movie, or playing a video game. Once viewers remember that they're watching fiction (usually due to bad writing like {{Said Bookism}}s, or [[FridgeLogic something not making sense]]) their ability to escape into the story drops drastically. Some [[{{Postmodern}} postmodernist]] writers and directors, like Creator/BertoltBrecht and Creator/HideoKojima, deliberately invoke this trope to point out the downsides of escapism, by deliberately making the audience aware of the unconscious processes involved.
* Try and do something simple like putting on a coat or tying your shoelaces ''while explaining every step carefully'' to an onlooker. Suddenly getting dressed has never been harder.
* This is common for anyone with a prosthetic leg. They have to relearn how to walk and balance themselves as their body is used to doing it one way, and they are trying to mentally go through the steps. One of the most common ways to get around it was to literally distract the patient in his therapy after they had proven able to do all the motions required so that they ''stop'' thinking about it. It still usually takes a few weeks.
** They also have to deal with the severely reduced tactile feedback from the skin and muscles that used to be there. You don't consciously notice, but your brain receives and processes literally thousands of sensations every second. When a person loses a significant part of their body, like a leg as stated above, those thousands of messages are basically replaced with "FILE NOT FOUND", so the brain has to create workarounds.
* A variation on the above can happen after a trip to the dentist. You mostly can’t talk straight because you’re concentrating so much on deliberately moving the tongue and lips you can’t feel, but if you don’t think about it too hard, they’ll still generally do what they’re supposed to do and you’ll be surprisingly comprehensible.
* [[DoorDumb Does this door open inwards or outwards?]]
* A condition called [[http://en.wikipedia.org/wiki/Spasmodic_dysphonia spasmodic dysphonia]] causes the sufferer to be unable to speak in spontaneous conversation, though they can often still speak in routine ways such as singing, rhyme, recalled speech, or vocal reading; acts which circumvent the process of coming up with words.
* Take up any martial art or combat sport and after becoming just a bit more skilled than a beginner, think about that perfect spinning backfist, left hook, or lunge. You are quite likely to fail the execution.
* People rarely get scared of the dark until they realize they are in the dark. For example, if you wake up in the middle of the night to urinate, then remember that you're afraid of the dark, you'll run straight back to your room.
* Something similar can happen to actors on stage. After so much rehearsing, your movements, facial expressions, gestures, and the lines you're speaking turn into muscle memory. The times you forget a line or an entrance are usually when you're thinking too much about what comes next.
** Related to this, some autistic people may rehearse movements, facial expressions, dialogues, and gestures until they're pretty much automatic in order to come across as more "neurotypical"[[note]]Neurotypical people don't have any mental illnesses or developmental disorders - what current society considers "normal". Neurodiverse people mimicking neurotypical behaviors and social norms in order to "fit" into society is called "masking". Non-autistic people are referred to as "allistic".[[/note]]. The final results of this effort may vary, but even if the "act" is unconvincing it can still always get worse if attention is brought to the flaws in the performance, as this makes them consciously aware of their behavior. Their attempts to avoid the flaws in their performance may lead to their act deteriorating (out of anxiety and overwhelm) until their movements are more akin to those of [[UncannyValley possessed marionettes.]]
** Actors and public speakers have gone their entire lives not thinking for a second about what to do with their hands when they're talking and looking perfectly natural. Get them up on stage and they're suddenly struck by the compulsion to hide their hands in their pockets, and when told they can't do that (because it looks awkward) they spend the entire time thinking about their hands and not knowing what to do with them, generally coming up with a really strange posture that looks like they were frozen halfway through a "put up your dukes" manuver. In one of the ''ComicStrip/{{Dilbert}}'' books, Scott Adams drew characters in a similarly unnatural posture and commented in the margins "People really do hold their arms like this when they're being mentored."
* Marching band is the same way. Memorizing the 8 minute marching routine which varies step size and direction all the time and 8 minutes worth of music quickly becomes muscle memory and you don't have to think about what you're doing. But fall down, miss a step, or a note and suddenly you don't know what to do until you get out of your own way.
* Next time you sign something, think about how you actually do your signature...
* When running down stairs, do not suddenly think "Which foot goes next?" You will trip. And likely die.
* The sworn mortal enemy of sufferers of obsessive thoughts (PTSD, OCD, etc) is indeed not the obsessions, but the brain that is obsessing in the first place. It's called "ironic processing", and what happens is the victim tries to not think about the obsession. So their brain reminds them not to think about it... by thinking about it. The more they try not to think about it, the more they end up thinking about it by their brain reminding them not to think about it. This trope is why the best thing for obsessive-thought-sufferers to do is distract themselves with something else entirely.
* Even though humans don't have nearly as many legs as centipedes, we can suffer from the same problem. Next time you walk, try to think about how you walk, and especially how you ''look like'' when you walk. You will still be able to walk, but you'll likely do it more clumsily and awkwardly than before. It is a problem that many people have tried, especially when they were around someone of the opposite sex; they walk perfectly normally, but due to nervousness they think they look stupid, and the result is that they really end up walking in a stupid way.
* In Australia, both English and American spelling is acceptable. Most people can just type without thinking, but if you think about it too hard, you forget how to spell words like colour (color? colour? COLOR?) entirely. It's worse if you try to think about how you spelt it in the past.
* An alarming number of perfectly common-or-garden words, if you stop and actually think about them properly, can suddenly look really peculiar -- to the extent that you might doubt your lifetime's acquired knowledge. That the English language, for one, is full of spelling and pronunciation quirks (even aside from the variations between different Anglophone countries) can make a word like 'mortgage' or 'choir' abruptly seem so odd it becomes impossible to believe your own ability to spell it. Or you may find there's certain words you're able to ''write'' perfectly fine, but nevertheless stumble over where to place the letters when you have to consciously ''type'' them in the correct order.
** Proper nouns -- personal names in particular -- can suddenly look pretty ''weird'', because they may derive from a variety of ancient linguistic roots and don't necessarily have anything else especially analogous to them in modern everyday language. Think for a minute about what exactly that 'h' is doing in the middle of the name John, for instance, and all of a sudden one of the most common and normal forenames in the English-speaking world becomes a minefield. (Perhaps unsurprising, in this context, is the number of times you can find non-native speakers on e.g. [=YouTube=] misspelling it 'Jhon'.)
* A common issue with teaching anything physical, from sports to dance to martial arts. A student will often ask the teacher something they do not consciously think about ("Do you position your foot this way or that way?"); if the teacher is lucky, they can just run through the routine of whatever they're doing and let muscle memory answer. If they're unlucky, the fact that they're thinking about it will bias their actions and leave them unsure about which way is actually correct. Prudent students soon learn to simply ask the teacher to demonstrate whatever part of the routine they're having trouble with and watch for the answer, rather than directly asking about it.
* This comes up whenever there are multiple ways to do the same task, like driving automatic or manual, mouse-clicking versus keybinding in [=MMOs=], etc. Proponents of both will claim whichever they learned first is superior because that's how they learned. They will also claim the other way is more awkward because they fall into this trope trying to do things differently from the way they are used to and don't want to give it the week or so of practice necessary to gain proficiency.
* 5-time ''Series/{{Jeopardy}}'' winner Jerome Vered recounted how during his first game, he struggled to ring-in early on until realizing he was too worried about ringing-in. Once he stopped worrying and focused more on answering the questions, he began dominating the game.
* Similar to the aforementioned golf tricks, fast pace card games such as Speed can involve psychological tactics to trip up other players. For example, questioning the legality of a play can cause the opponent to hesitate, wondering if they had played their cards in the right order and giving yourself an opportunity to respond.
* In general, the harder one may think about a particular problem the less likely they are to think of the solution. After a while, simply when taking a nap or even a bathroom break, the solution will come to one's mind subconsciously.
* Mistyped the PIN to your phone or bank account? Don't think about how two more incidents will lock you out permanently. Or where you probably mistyped. Or what your PIN even is. 4399 or 4398?
** Even worse in some countries like Germany where you can't appoint your own bank PIN: locking yourself out of your bank account is fine - if you remember your PIN later or have it written down somewhere. If you don't, then the bank will take your card, destroy it and send you a new one with a new PIN which can take almost a week (since they send them separately). Worse, if your muscle memory returns and you suddenly remember your old PIN, but not the NEW one (and you're fucked, if your new one is very close to your old one, making mistyping a guarantee). There had been people that made it into boulevard magazines who were stuck in this dilemma until they cheated by having a fake phone number with the PIN in their contacts or similar.
* Multiplication for young children. They usually at first only recite the tables before knowing them. So want to make them trip up and forget everything? Just mess with orders: 2x1? 2x2? 2x3? ''5x6?''
* Modern fighter aircraft have ''intentional instability'', which makes them respond faster to control inputs, thus becoming more maneuverable (there are other benefits as well). This means that they need to have a "smart", i.e. computer-assisted, control system that helps the pilot by translating his/her stick movements into the necessary control surface actuations. This works well as long as the pilot is able to remain relaxed about the aircraft not ''exactly'' responding to his/her input. If the pilot tries to force a maneuver against the control system's efforts it can break down very quickly and hard.
* Making out or sexual intercourse can turn into an absolute minefield if one or both partners start overthinking what they're doing. There's a reason the most common advice one can receive when it comes to lovemaking is "just go with it" or some variation thereof; performance anxiety, societal pressure to be a good lover, and your partner's preferences all come roiling together into a horrendous hormonal bomb that you then have to try and defuse.
* Ask an avid reader to read a kid's book out loud, and they're likely start sounding like they're incapable of reading. Experienced readers learn short cuts when reading to themselves, like skipping over words when they think they know what they will be or not bothering to figure out how to pronounce a complicated name, which work quite well reading alone, but which can't be done when reading out-loud. Of course once one notices that these methods don't work it's easy to get stuck thinking about what your're reading so much that you become even more prone to stumbling on words and generally sounding like you're still a beginning reader.
* [[ThoughtAversionFailure If you tell someone to forget about something, or to not think about it, the exact opposite will happen.]]
[[/folder]]

* In ''Film/TheKingsSpeech'', Lionel Logue points out that this is Bertie's problem (though it's a significant problem and not easily surmounted) by having him recorded reading ''Theatre/{{Hamlet}}'' while listening to music that make it impossible for him to hear himself. It's not until much later, after getting drunk and dismissing Logue as a crackpot, that Bertie listens to the recording... and hears himself speaking without a stutter for the first time in his life.
* Referenced in ''Film/TheLastSamurai''. Nathan Algren's fights training fights always end quickly (and with him sporting a fresh bruise), until Nobutada explains that Algren has "too many mind -- mind the sword, mind the people watching, mind your enemy. Too many mind. No mind." Notable in that this is legitimate advice and something many martial arts schools teach. It does, indeed, work like a charm, but you're far more likely to hit your sparring partner harder than you should.

* ''Webcomic/AGirlAndHerFed'': Psychic healer Smithback tried to pass his knowledge to Hope (The Girl). But Hope's traditional medical training interfered with her understanding of Smithback's techniques, to the point where they stopped the healing lessons.