[[quoteright:350:[[Webcomic/TheOrderOfTheStick http://static.tvtropes.org/pmwiki/pub/images/SoftUnderdevelopedSkull_8349.png]]]]

A explanation for a character's eccentricity, ditziness, lack of intelligence, brashness, etc is for them (or others) to harm his head as a infant or a child. A possible cause of this trope could be that they were accidentally dropped by their AlcoholicParent, who had a little too much to drink. In some cases, they were actually pretty intelligent before the incident happened. One variation of this trope is that the character's mental deficiencies are not from a head injury but by them ingesting something harmful and toxic such as paint chips or [[OneDrinkWillKillTheBaby alcohol]]. Another is that the brain damage was due to the character being deprived of something that's essential or substantial to having a relatively healthy body.

If this trope is PlayedForLaughs, a character may jokingly or cheerily suggest to the others that a daft moment that another character (who usually has no disabilities and is mostly functional otherwise) just had was due to them injuring their head in their childhood. However, if it's PlayedForDrama and the character genuinely had head trauma in the past, it's used as a indication that the character was abused as a child or had a very dysfunctional childhood (they may also have a head deformity because of it).

Related to EasyAmnesia, TapOnTheHead, HardHead, CirclingBirdies.

A classic example of a HilariouslyAbusiveChildhood.

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!!Examples:

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[[folder:Anime and Manga]]
* In ''Anime/DragonBallZ'', it's stated that the reason why Goku doesn't share the violent nature of Saiyans is because he landed on his head while he was a baby. It's also why he's a bit of a simpleton.
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[[folder:Comic Books]]
* A variation of the trope occurs with Martin Soap from ''ComicBook/ThePunisher'': We see the nurse dropping him on his head just after being born, but he doesn't end up with any mental handicap for it (it's just there to show the crap life shoves on him started very early and never let up).
* Cyclops of ''ComicBook/TheX-men'' suffered brain damage when he was a child after being pushed out an airplane with his brother (Havok) with only one parachute. Besides amnesia, the part of his brain that would have regulated his optic blasts was damaged, causing them to be "on" all the time. The blasts are only controlled by his ruby quartz visor and his eyelids.
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[[folder:Fan Fiction]]
* In a number of ''Manga/AxisPowersHetalia'' fanfictions, such as ''FanFic/TheHearthSeries'', it's revealed that Germany can't remember his childhood as the Holy Roman Empire because of injuries. Given that the series has Holy Roman Empire going to ''war'' before his "death", it's not that big of a leap.
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[[folder:Film]]
* In ''Film/TheGoonies'', it's implied that Sloth's deformity was caused by being dropped as a baby. When Ma Fratelli tries to calm him down by singing "Rock-a-bye Baby", Sloth reacts to the line "the baby will fall" as if it has unearthed RepressedMemories, precipitating his HeelFaceTurn.
* ''Film/ShadowOfADoubt'': The film implies that a brain injury suffered when he was hit by a car as a child is what caused Uncle Charlie's "[[SerialKiller problem]]".
* A RunningGag in the ChrisFarley movie ''TommyBoy'' has people ask [[ManChild his character]] if he ate paint chips as a child.
* In ''{{Film/Bio-Dome}}'', there's a scene where one of the dumbasses' mothers is holding the other's head under water to teach them how to hold their breath for long periods of time.
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[[folder:Folklore]]
* A Russian folk parody of an old Soviet song says: "Our youth threw us onto campaigns with sabers, our momma dropped us head-down on ice, and if our momma didn't drop us head-down on ice, no campaign with sabers would be possible". Original Russian: "Нас бросала молодость в сабельный поход, нас роняла мамочка головой об лед, кабы не роняли нас головой об лед, то не состоялся бы сабельный поход".
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[[folder:Literature]]
* In ''Literature/BraveNewWorld'', it's rumoured that Bernard Marx's eccentricities are caused by an excess of alcohol in his blood-surrogate while he was being [[DesignerBabies grown]].
* In ''Literature/OfMiceAndMen'', George tells the ranch owner that Lennie was kicked in the head by a horse as a child to explain why he's mentally slow. Lennie has to ask George about it afterwards as he doesn't know whether it's true or not - George then says it's not true.
* In ''Literature/TheGrapesOfWrath'', Pa Joad blames himself for his son Noah's slowness as he tried to deliver him on his own, and ended up distorting his head.
* PlayedForLaughs at one point in the ''{{Malloreon}}'', when Garion comments that maybe his tendency to charge into dangerous situations without thinking about the danger is because his Aunt Pol dropped him on his head as a baby.
* The Soviet book ''Literature/KingdomOfCrookedMirrors'' briefly features a character who was dropped on his head as a child. Since then, he can only count to three.
* In ''Literature/TheElenium'', the main characters meet a secondary, clearly handicapped character who was hit on the head when young by a cow.
* In ''{{Literature/Horns}}'', [[spoiler:It is heavily implied to be the reason why Lee Tourneau is a remorseless psychopath.]]
* In the ''{{Literature/Emily of New Moon}}'' trilogy, Emily's Cousin Jimmy is "simple," due to her Aunt Elizabeth causing him to fall into the well when they were children.
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[[folder:Live-Action TV]]
* In ''Series/KenanAndKel'', Kenan once implies that Kel's lack of common sense (and otherwise intelligence) was the result of him being dropped on his head as a child.
* ''Series/TheFreshPrinceOfBelAir'' has a slight variation, when Will asks Carlton if he was deprived of oxygen.
* ''Series/MarriedWithChildren'' had a flashback in which Kelly (TheDitz) was shown to be very intelligent as a young girl, until she hit her head during a car ride.
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[[folder:Newspaper Comics]]
* ''ComicStrip/{{Garfield}}'': Jim Davis opens the comic's 20th anniversary book by claiming, "I was born July 28, 1945, in Marion, Indiana, and was promptly dropped on my head - [[SelfDeprecation which explains my lifelong desire to become a cartoonist.]]"
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[[folder:Video Games]]
* PlayedForDrama in ''VideoGame/TheLongestJourney'': April's dad was drunk and dropped her when he held her as a baby for the first time, causing a serious cranial trauma that took several years to heal, during which she couldn't walk or speak. Although she eventually grew up normal (as normal as [[spoiler:a half-dragon Shifter can be]], anyway), her father's repressed guilt over the incident resulted in her very strained relationship with him and eventually led to her running away from home before the start of the game.
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[[folder:Webcomics]]
* ''Webcomic/EightBitTheater'': Black Mage asks [[GeniusDitz Fighter]] whether he was dropped on his head a lot as a child, to which Fighter answers, "Maybe..." This is immediately followed by a flashback to Fighter's childhood, with young Fighter exclaiming how happy he is to have power lines in his back yard and plenty of paint chips to eat.
* A flashback in ''Webcomic/TheOrderOfTheStick'' explains Elan being TheDitz as a result of his brother [[EvilTwin Nale]] continually {{Dope Slap}}ping him when they were babies.
* ''SlightlyDamned'': Buwaro's frequent blows to the head (fail rock catches) might go some way to explain his lack of intelligence, but there are factors, such as damaged to his egg before birth and being left alone for long periods of time.
* In ''Webcomic/BobAndGeorge'', when MegaMan [[spoiler:actually Helmut in disguise]] continues talking about his evil plan even though Roll is [[RightBehindMe right behind him]], she asks if he ate paint chips as a child. He states that it's very possible.
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[[folder:Web Videos]]
* ''TwoBestFriendsPlay:'' In one episode, Matt's being more of a ditz than usual, so Pat asks him whether he [Matt] ate paint as a child. Matt immediately answers, "You mean wall candy?"
* In ''[[WebVideo/DragonballAbridged Dragonball Z Abridged]]'', Goku fell on a rock head-first when he was still a child. And he's noticeably more ditzy and absent-minded than his canonic self.
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[[folder:Western Animation]]
* ''WesternAnimation/AllGrownUp'', the sequel to ''WesternAnimation/{{Rugrats}}'', mentions that Dil is so strange because Phil and Lil dropped him on his head when they were babies.
* On ''WesternAnimation/RegularShow'', Mordecai and Rigby travel back in time and meet young Pops, acting lucid and sane, unlike the CloudCuckooLander he is in the present. Later during a car chase, they hit Pops, who then starts giggling like present-day Pops.
* One episode of ''WesternAnimation/TheSimpsons'' reveals that Homer is an idiot because he stuck a crayon up his nose as a child and got it jammed into his brain.
** In "Itchy and Scratchy: The Movie", he told Bart when he was a kid we wanted a bike but his dad wouldn't let him. So he tries holding his breathe so his dad would give in. But he passed out and had to be rushed to the hospital, where the doctors say he has suffered brain damage.
-->'''Bart:''' Dad, what's the point of this story?\\
'''Homer:''' I like stories.
* On ''WesternAnimation/{{SpongeBob SquarePants}}'', it is often suggested that Patrick's stupidity is the result of frequent head injuries. In "Squidward the Unfriendly Ghost", Patrick mentions that he knows a lot about head injuries, then spaces out mid sentence. In "Big Pink Loser", [=SpongeBob=] tries to discourage Patrick from mimicing him by hitting himself with a hammer, to which Patrick responds, "I've been doing this way before I started copying you."
* In an episode of ''WesternAnimation/TheBeatles'', [[JohnLennon John]] sews the money from last night's concert into [[RingoStarr Ringo]]'s pocket to keep it from getting lost.
--> '''John:''' There! Safe as in a mother's arms.
--> '''Ringo:''' [[TheDitz Me mother dropped me once]].
--> '''John:''' I know. That's why I didn't sew it in your hat.
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