Kelso: Yes! I WAS! And up until now, everyone had the good grace not to mention it!
A explanation for a character's eccentricity, ditziness, lack of intelligence, brashness or the like is for them (or others) to harm their head as a infant or a child. A possible cause of this trope could be that they were accidentally dropped by their Alcoholic Parent, 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 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 Played for Laughs, 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 Played for Drama and the character genuinely had head trauma in the past, it's used as an 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 Easy Amnesia, Tap on the Head, Hard Head, Circling Birdies. Contrast Early Personality Signs, which are hints of someone's future personality but unlike Childhood Brain Damage, it's implied that it's natural and not the result of an injury.
A classic example of a Hilariously Abusive Childhood.
- No-Rin: In the English dub of episode 8, Yoshida angrily asks Kousaku if he was dropped on his head when he calls Kei (whom Yoshida has a crush on) to come.
- Dragon Ball Z:
- When Goku was a baby he was just as violent as all Saiyans are, until he accidentally hit his head and became the kind-hearted Idiot Hero everyone knows and loves. It's even lampshaded by his evil older brother Raditz, who point-blank asks Goku if he did hit himself in the head as a child and Goku not only confirms it, but even adds "I still have the scars, you know."
- The Big Bad of Dragon Ball Z: The Tree of Might, Turles, represents what Goku would have been like without his childhood brain injury. The result is an Identical Stranger who has Goku's love of food and fighting but none of his empathy.
- Asterix: Obelix got his Super-Strength from falling in a cauldron of magic potion when he was small. Although it gives him a useful power, it's played as this trope, and there's several implications that it permanently altered his personality into the sweet, childlike attitude we see — for instance, when reverted to childhood by magic, he loses his power and becomes serious, deep-thinking and quite grumpy.
- Batman: The villain Black Mask was dropped on his head by his parents while being born. This was just the first incident in a long line of abuse and neglect his parents inflicted on him. It's implied that the incident may have been a contributing factor in Black Mask's unstable mental state and extreme mood swings.
- The Grim Adventures of Billy & Mandy: "Better Luck Next Time" has Billy and Mandy sent through time after getting sucked into Grim's Cosmic Cuckoo Clock. They land in the bedroom of Billy when he was an infant. He was apparently quiet, studious and intelligent back then, but when present-day Billy goes into his stupidity dance, baby Billy is suddenly corrupted and becomes stupid as well.
- Marvel Universe:
- The Punisher: A variation of the trope occurs with Martin Soap. 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 that the crap life shoves on him started very early and never let up.
- X-Men: Cyclops 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.
- Jim Davis opens the comic's 20th anniversary book by claiming that "I was born July 28, 1945, in Marion, Indiana, and was promptly dropped on my head — which explains my lifelong desire to become a cartoonist."
- In the strip itself, Jon's often-eccentric behavior has been implied on a few occasions (such as this one) to be an effect of several head injuries he suffered growing up on a farm.
- Asylum (Daemon of Decay): Rainbow Dash had an accident as a foal that left her disabled. She can fly but even with physical therapy she isn't on par with most other pegasi. She received head trauma that left her with a Speech Impediment, and which might be part of the reason for her temper.
- Fairly English Story: Minato suffered from brain damage in the car accident which killed his parents. However, this didn't harm his intellect or emotional maturity. Rather, it leaves him unable to naturally convey emotions without intentionally trying.
- Farce of the Three Kingdoms: Liu Shan is implied to have brain damage from being flung on the ground as a baby. He's actually quite Genre Savvy, but extremely passive.
- Gensokyo 20XX: Played with with Reimu and Chen. In Reimu's case, this is a variant and a subversion in that, aside from being age-regressed, she technically isn't a child but this trope comes into play when she eats rat poison in 20XXV, the effect of which leaves her near-blind and a heavy sleeper, though her intelligence remains intact, then again, in 20XXII, she was injected with sedatives every few hours for screaming, so that may have also had an effect on her that either faded with time or wasn't so apparent until now. In Chen's case, she was brain damaged as a result of her suicide attempt by drowning during the events of 20XXIV, which left her unable to talk. This explains her speech impediments that we see during 20XXV.
- The Hearth Series: 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.
- Kill la Kill AU: Nui fell on her head when she was a year old and, apparently, Satsuki chocks the fact that she doesn't take messages too well because of that.
- Team 8: Kurenai wonders if Gai had been dropped several times on his head as an infant. She concludes more realistically that the stronger a jonin is, the more wackier they behave (and fears that she will become eccentric as well).
- This Bites!: According to Ace, Luffy didn't get enough oxygen as a child, and chewed on the bars of his crib, which had lead paint. Also, Garp apparently believes that concussions don't have any side effects, and passed this belief on to Luffy. Cross comments that that explains so much.
- Witching Hour: According to village rumor, Nick is always happy because he was once kicked in the head by a mule when he was younger.
- Happy Feet: The fact that the penguin Mumble's egg was dropped by his father is the main reason he can't sing, and the film does everything it can to compare it to this trope without actually saying it.
- Pokémon: The First Movie: This is possibly the reason Mewtwo goes insane. As a child, he was not allowed to come to terms with fellow clone Ambertwo's passing away naturally. The scientists gave him a heavy tranquilizing serum to put him back to sleep until he developed into an adult. He wakes up confused, bitter and angry with little to no memory of why.
- Yogi the Easter Bear: Paulie at one point asks his stupid henchman Ernest if his mother dropped him when he was a child.
- Alice Through the Looking Glass reveals that the Queen Of Hearts used to be normal until she fell and hit her head as a child, which caused it to swell to the size that it is.
- Bad Santa: In the first movie, Willie asks "the Kid" if he's intellectually slow due to the fact that he was dropped on his head as an infant.
Willie: What is it with you? Somebody drop you on your fucking head?
The Kid: On my head?
Willie: Are they gonna drop you on somebody else's head?
The Kid: How can they drop me onto my own head?
Willie: No, not onto your— would... God damn it! Are you fucking with me?
- Bio-Dome: In a flashback, Doyle's mom is seen holding his friend Bud underwater in an attempt to teach him to hold his breath. It's implied that she did the same thing to Doyle too, which may explain why they act so immature as adults.
- A Child Is Waiting is set at an institution for mentally disabled children. It's explained that one of the most common causes of their disabilities is being deprived of oxygen during birth.
- Nicky from Dominick and Eugene "fell down" and hit his head when he was a kid, resulting in a learning disability and total amnesia of everything that happened before the accident. Later he learns it was actually caused by his father violently beating him.
- The Goonies: 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 Repressed Memories, precipitating his Heel–Face Turn.
- Harriet: Played for Drama with brutal historical accuracy. Harriet Tubman really did have her skull fractured in childhood, when an angry overseer threw a two-pound lead weight at another slave and she accidentally got in the way. She survived, but suffered from fainting spells for the rest of her life.
- Joker (2019): After reading his adoptive mother's records from Arkham Asylum, Arthur discovers that he has suffered brain damage in his childhood due to the abuse he received from her and her boyfriend, which can serve as a possible explanation for his mental issues.
- Like Normal People: Virginia was removed from the womb with forceps, leaving her with a dent in her skull and a limp in addition to her intellectual disability.
- Shadow of a Doubt: The film implies that a brain injury suffered when he was hit by a car as a child is what caused Uncle Charlie's "problem".
- Tommy Boy: A Running Gag has people ask his character if he ate paint chips (or lived near powerlines) as a child.
- 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."
- Implied in the following Last-Minute Baby Naming joke:
Lily walks up to her father one day and hops in his lap. "Daddy," she asks, "why am I named Lily?" "Well," he says, "because when you were born, the petal of a lily flower floated through the window and landed on your head." She smiles and hops away.
Later that day, Mary walks up to her father and jumps on his back. "Daddy, why am I named Mary?" He smiles. "Because when you were born, the petal of a marigold was caught by the breeze and landed on your head." She laughs and skips away.
That afternoon, Cindy walks up to her father and sits on his feet. "GAHHNURGH! HHUADANNGUNGDGFURRRG? HRUGUN HURGN DURRRGH?" Her dad sighs. "I love you too, Cinderblock."
- Angela's Ashes: Angela's brother and Frank's uncle Pat is slow-minded and is said to have been dropped on the head as a baby.
- Battle Royale: Kazuo Kiriyama is emotionless due to brain damage he sustained at a very young age. In the manga, being shot in the head restores his ability to feel right before he dies.
- Brave New World:
- It's rumoured that Bernard Marx's eccentricities are caused by an excess of alcohol in his blood-surrogate while he was being grown.
- Excess alcohol in a fetus's blood-surrogate is deliberately done to those destined to be in the Delta or Epsilon classes, so that they're the right amount of intelligence needed for their designated task and no more. Notably, Huxley wrote about this before Fetal Alcohol Syndrome was recognized and named.
- Boots from Cemetery Bird was shoved down a staircase by his father when he was six. His heart stopped for five minutes, during which he had a Near-Death Experience in which Jesus and the angels brought him back to life. Ever since then he's suffered from severe seizures, for which he is heavily medicated.
- Chocoholic Mysteries:
- In Frog Frame-Up, Patsy Waterloo states that her brother Hershel Perkins (who's widely regarded as the town crank, has gone missing and is soon to become the book's murder victim) was officially diagnosed with "minimal brain damage caused by a birth injury".
- In Castle Clue, Kathy Street is noted as having had some kind of brain damage at birth; her older twin sister Margo has been taking care of her for most of her life.
- Dragonriders of Pern: Played for drama. The mentally-disabled servant Camo, a secondary character in the Harper Hall trilogy, is eventually revealed to have suffered severe oxygen deprivation during his birth.
- The Elenium: The main characters meet a secondary, clearly handicapped character who was hit on the head when young by a cow.
- Emily of New Moon: Emily's Cousin Jimmy is "simple," due to her Aunt Elizabeth causing him to fall into the well when they were children.
- Hurog: Subverted. Ward pretends that a violent beating by his father caused brain damage to make his father believe he's a harmless idiot. (His father introduced the tradition of Klingon Promotion and fears that Ward might want to continue it.)
- John Steinbeck:
- The Grapes of Wrath: 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.
- Of Mice and Men: 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.
- Kingdom Of Crooked Mirrors briefly features a character who was dropped on his head as a child. Since then, he can only count to three.
- The Malloreon: Played for Laughs 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.
- In Mr. Revere and I, Sherry's original owner, Sir Cedric, has a stutter because he fell from the nurse's arms when he was two.
- My Next Life as a Villainess: All Routes Lead to Doom!: The story starts with Catarina getting a massive blow to the head at age eight and getting Past-Life Memories in the process. By fifteen, she has developed an impulsive and spacey personality that leads several characters to wonder in-universe if she's suffered some brain damage from the blow to her head. Out-of-universe, it's implied but never stated that the "Monkey Girl" persona from her previous life has completely overwritten whatever personality and reasoning Catarina had previously.
- Otto of the Silver Hand: Brother John fell from his nurse's arms when he was a small child. His parents didn't know what to do with a mentally disabled son, so they sent him to live at the monastery.
- Romance of the Three Kingdoms: Liu Shan is renowned as an inadequate successor to Liu Bei, with his childhood nickname "Adou" becoming a Chinese byword for someone utterly useless. This is probably because his father had dashed his infant son to the ground in anger that his general Zhao Yun had risked his life to rescue the kid, saying, "[b]rothers are as hands and feet; wives and children are as clothing. You may mend your torn dress, but who can reattach a lost limb?". Worth noting that this is basically a liberty taken by the author; in the actual history that the novel was based on, Liu Bei didn't throw the infant Liu Shan on the ground and inflicting him with the trope, his inadequacy came rather naturally.
- Jonas Morrison from Saving Max has brain damage from a childhood seizure caused by his mother's medical abuse. The result is that he's The Unintelligible and severely intellectually disabled.
- The Amanda Show: In one segment, Debbie is asked if she was dropped on her head as a child. Her answer is "Sure, lots of times!"
- In Bunk'd, it is revealed that the reason Finn acts so strangely is when he was a baby, Lou accidentally bumped his head against the refrigerator door. This resulted in her being afraid of babies, or rather, hurting one by accident.
- The unsub in the Criminal Minds episode "Proof" didn't get enough oxygen while he was in the womb, which lead to him being developmentally disabled. This isn't given as an explanation for his killing spree (one of the only times a mental disorder isn't brought up as a cause), just to provide context for his ruse: he appears harmless and confused, which prompts women to get into a vulnerable position while trying to help him.
- A victim of the week on CSI: NY had this after trying to fly from a window as a little kid. He lived in a home and got killed trying to stop a orderly from selling medicine. He still liked being a superhero and was found dead in his costume after trying to stop a sale on the street.
- Frasier: Niles tells Frasier than one of Daphne's brothers, who mostly speaks in incomprehensible mumbling, was dropped as a child. Worse yet, he was actually dropped on another brother.
- The Fresh Prince of Bel-Air has a slight variation, when Will asks Carlton if he was deprived of oxygen.
- Friends: When Ross and Monica are reminiscing about some of the ways they fought as kids, Ross mentions he once stuck a broom handle into the spokes of Monica's bike, causing her to flip over and hit her head on the curb. Monica doesn't remember that happening, but she does remember people telling her it happened.
- Game of Thrones: Tyrion Lannister recalls the story of his cousin Orson, who was dropped on his head by a wet nurse when he was a baby. Every day he would sit in the gardens, smashing beetles with a rock, and Tyrion could never figure out why he was doing it. He did it for the rest of his life until he died from being kicked in the chest by a mule.
- Kenan & Kel: Kenan explains in a minor Running Gag that Kel's lack of common sense (and otherwise intelligence) was the result of him being dropped on his head as a child. Kel invariably agrees: "Yes - Many times!" This is usually in situations where he needs to excuse Kel's odd behaviour, so it may or may not be true.
- The Good Doctor: Melendez's little sister was brain-damaged by a tree-climbing accident as a child. The family became very poor because of her medical bills, and she now lives in a group home.
- Law & Order: Special Victims Unit: "Lead" has a murder suspect who licked lead-based paint off his toy cars as a child; the seizure and the ensuing brain damage caused him to grow into a Psychopathic Man Child with a Hair-Trigger Temper. The toy company was sued and forced to pay his medical bills.
- Malcolm in the Middle: Dewey's odd behavior is apparently the result of Lois standing in front of a microwave oven while she was pregnant with him.
- Married... with Children had a flashback in which Kelly (The Ditz) was shown to be very intelligent as a young girl, until she hit her head during a car ride.
- That '70s Show, Kitty asks Kelso (aka The Ditz) if he was dropped on his head, as seen in the above quote.
- It's Always Sunny in Philadelphia: In "The Gang Buys a Roller Rink", it is revealed that Dee Reynolds used to be a cheerful, kind, and ambitious young woman before she received a traumatic brain injury when she lost control at a roller rink and hit her head on the floor (due to Charlie tampering with her skates), giving her the rude, aggressive, impulsive, and selfish personality she is famous for.
- Stranger Things: Steve Harrington apparently learned how to crawl backwards as a baby, eventually sending himself tumbling down a staircase and hitting his head. Nancy, upon hearing this story, notes that it explains a lot about his current persona.
- The Thundermans: Billy is easily the dumbest member of the family. It's because Barb apparently gave birth to him in mid-air (Hank was frantically flying her to a superhero hospital), an experience she doesn't want to repeat with any other kid.
- Noël Coward: "I wonder what happened to him?" mentions a man whose dim-wittedness is attributed to having been dropped on his head when he was two years old.
You remember Monroe from the P.A.V.O.?
He was tall-ish and mentally dim.
All that talk of heredity can't be quite true,
He was dropped on his head by his ayah at two.
I'm certain by now he'll have reached G.H.Q.
I'm sure that's what happened to him!
- Bill Cosby has a Running Gag in his concert film Bill Cosby: Himself about children who do something their parents won't allow, get caught in the act, and then respond to the parent's inquiries on why they did it with "I don't know". Each time this scenario comes up, he refers to it as "brain damage".
- Warhammer: When the ogre warlord Ghark Ironskin was still a whelp, his father grew annoyed at how slowly he ate and hit him over the head with his iron-banded war club. One of the nails remained lodged in Ghark's cranium, where it remains and rusts to this day, and is rumored to be the origin of his obsession with iron.
- The Light in the Piazza: Margaret reveals that the reason for her daughter Clara's childlike behavior is that she was kicked in the head by a pony, causing her to fall and hit her head. This left her essentially stuck mentally at the age of 12, even though she's now 26. This is why Margaret and her husband oppose her marrying Fabrizio though Margaret comes around at the end of the show without telling Roy.
- Animal Crossing: Cranky villagers will state that Pascal was hit by a soccer ball in the head when he was a child, and after that he began spouting unusual philosophy. It's unknown if that's true or just the animals being rude.
- Baldur's Gate II: Should a male player character make the mistake of saying that he "doesn't rightly know" where to go next with Jaheira during a very bad time for her, she will accuse him of sounding like he'd been dropped or kicked on his head as a child.
- Ducktales: The remake has Scrooge ask Launchpad if he suffered head trauma when he was younger in the Amazon level.
Scrooge: Launchpad, were you dropped on your head much as a child?
Launchpad: All the time! Why?
- Fallout: Max Stone, one of the character presets, was dropped on his head by the labor bot in his backstory.
- Fire Emblem: The Binding Blade: The poison that a teenaged King Zephiel was tricked into taking as a young man is repeatedly stated to have been the catalyst that left him not quite the same. A number of similar poisons in the real world (such as mercury) can and do result in personality-warping brain damage, including paranoia, increased aggression, and decreased impulse control... just like it happened to him.
- Heart De Roomate: Marumu's emotionless Cloud Cuckoo Lander tendencies are revealed to be the result of a fall off of a small cliff some years before. This is not quite Played for Drama, since this is revealed by her brother, who explains that she's been in therapy in the meantime and thanks Yusuke for helping her along (since their relationship escalated, she's been showing more signs of improvement).
- The Longest Journey: Played for Drama. 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 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.
- The Urinal Game gives the player the opportunity to try to share urinals. If you do it with the large, muscular guy, you get the message "How many times were you dropped as a child?".
- 8-Bit Theater: Black Mage asks 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.
- Bob and George: When Mega Man actually Helmut in disguise continues talking about his evil plan even though Roll is right behind him, she asks if he ate paint chips as a child. He states that it's very possible.
- Darwin Carmichael Is Going to Hell: (Mostly) Played for Drama. Due to Darwin's negligence as a baby sitter, the future Dalai Lama falls out of his high chair as a baby. Consequently he has the mental capacity of only a child as an adult.
- The Order of the Stick:
- A flashback explains Elan being The Ditz as a result of his brother Nale continually Dope Slapping him when they were babies, as seen in the page picture.
- Later on, when Durkon's mother Sigdi asks to hold an infant, Durkon's son, her grandchild, Hilgya briefly questions whether it's safe to do so with one arm. Sigdi points out she raised Durkon with one arm, and Hilgya relents, with the caveat that nothing in her interactions with Durkon suggests he wasn't dropped on his head as a child.
- Slightly Damned: 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 damage to his egg before birth and being left alone for long periods of time.
- Looming Gaia: Itchy got brain damage as a toddler from his mother attempting to drown him, resulting in developemental issues as a child and irrational behavior as an adult.
- Madgie, what did you do?: This is why Doki has cerebral palsy. When she and Toki were born, she was deprived of oxygen at birth, being born second and at a later time than the latter. The same would apply Vielle, as she also cerebral palsy and her debut story doesn't say how long her mother was in labor.
- Dragon Ball Abridged: Much like his canon counterpart, Goku fell on a rock head-first when he was still a child. And he's noticeably more ditzy and absent-minded than his canonical self. The accidental dosage of bleach while at the hospital after defeating Vegeta likely didn't help matters.
- Empires SMP Season 1: Jokes have been made at Jimmy Solidarity's behest when it's revealed that he was born from a small, damaged egg in contrast to his sister Lizzie's large, undamaged egg.
Lizzie: You're telling me that the secret to our identity has been sitting in one of your chests this whole time?
Jimmy: Maybe. Maybe so, yes, probably.
Lizzie: You definitely came from the small damaged egg.
Jimmy: I'm... I am the small damaged egg, yes.
- Sam & Mickey:
- This is implied with Barbie, as, in response to her being yelled at for throwing Krissy, Margaret replies "What?! I used to throw you all the time and you turned out fine — in second thought, you're right."
- A throwaway line claims Chelsea is this due to Barbie throwing her around when she was a baby.
- Barbie retorts to Stacie exclaiming that "It's not [Yasmin]'s vault you're an idiot!" by confessing that it's her fault that she's an idiot, since Barbie took a lot of drugs while pregnant with her.
- Two Best Friends Play: 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?"
- Ultra Fast Pony: Rainbow Dash is aggressively stupid. "Pinkie's Day In" implies this to be due to her foster parents throwing her around when she was a child.
Mrs. Cake: You're not supposed to throw babies.
Rainbow Dash: Seriously? My second foster parents used to throw me all the time!
Mrs. Cake: That explains so much that I didn't care about.
- All Grown Up! mentions that Dil is so strange because Phil and Lil dropped him on his head when they were babies. Dil's mother Didi doesn't quite buy that, though, and thinks it's genetic from his father's side of the family, which isn't that farfetched a theory.
- The Amazing World of Gumball:
- In "The Origins", as an infant, Sussie can speak and dreams of being a lawyer. Then she's dropped on her head and starts speaking in the same gibberish she spouts as a junior high student.
- In "The Vase", the Watterson kids attempt to break the titular vase by giving it to Richard, whose hands are covered in butter, while telling him not to drop it. He doesn't, causing Gumball to angrily ask his father "Why couldn't you have managed that when I was a baby?" It's not exactly clear if he's being serious or accurate.
- The Beatles: In one episode, John sews the money from last night's concert into Ringo pocket to keep it from getting lost. When he comments that it's "safe as in a mother's arms", Ringo replies that his mother dropped him once. John says he knows — that's why he didn't sew it in his hat.
- Big Hero 6: The Series: Season 1's primary antagonist, Obake, had contracted a brain tumor from an experiment gone horribly wrong, and lost the ability to tell right from wrong. Not that he minds.
- The Critic: Jay Sherman's father admitted in a video will that he dropped Jay on his head when he was a baby, all day long.
- DuckTales (2017): After the family meets Donald's fellow Caballeros, José lets it slip that when Huey, Dewey and Louie were still eggs, Donald bet he could juggle them and ended up dropping one. Hearing this, Huey and Louie look at Dewey, who is not paying attention and blinks his eyes out of sync. Huey and Louie nod in silent agreement that the egg was probably his.
- Family Guy:
- A Cutaway Gag showed that Stewie used to be a hyperactive kid with a normal-shaped head, until he hit his head on the ceiling while jumping on the bed, squashing his skull into its current football shape and altering his personality.
- In "Peter's Daughter," Meg believes she's pregnant and is planning to marry the baby's father. Since Meg is against getting an abortion, Lois implies she could simply "Drink and smoke a lot." And then immediately adds if Meg's gonna go with that option she shouldn't stop halfway because otherwise she'll "Be stuck with Chris," implying this is the reason Chris is such an idiot.
- According to a couple of episodes, Peter is an example. After getting pregnant by Mickey McFinnigan, Thelma went to Mexico for an abortion, which was really getting beat like a pinata until Peter came out, while another suggests that he's the way he is because he got sick as a kid (he's shown unable to kick a soccer ball).
- F is for Family:
- Kevin is noted to have been drowning at the bottom of a motel pool for two minutes as a child.
- Implied with Phillip's younger brother Anthony, who barely speaks in full sentences, after Phillip played with Anthony's soft spot.
- Regular Show: Mordecai and Rigby travel back in time and meet young Pops, acting lucid and sane, unlike the Cloud Cuckoo Lander he is in the present. Later during a car chase, they hit Pops, who then starts giggling like present-day Pops.
- The Simpsons:
- "HOMЯ" reveals that Homer is an idiot because he stuck a crayon up his nose as a child and got it jammed into his brain. When it's removed, his intelligence actually becomes above average. That doesn't last, of course.
- In "Itchy and Scratchy: The Movie", Homer tells Bart when he was a kid, he wanted a bike, but his dad wouldn't let him, so he tried holding his breath so his dad would give in. He passed out and had to be rushed to the hospital, where the doctors said he suffered brain damage.
Bart: Dad, what's the point of this story?
Homer: I like stories.
- A flashback in "Moms I'd Like to Forget" shows Ralph Wiggum, a notoriously oddball character known for saying strange things, being held by his father as a baby drinking from a bottle when his father accidentally drops him. Afterwards, Ralph is no longer able to find the bottle with his mouth.
- In "My Octopus and a Teacher", Homer says that as a kid, he had a crush on his school nurse, and would repeatedly hurt himself to get to visit her. The fact that he lists the same method twice implies that he now has memory issues.
- SpongeBob SquarePants:
- It's 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 mimicking him by hitting himself with a hammer, to which Patrick responds, "I've been doing this way before I started copying you."
- In "Cephalopod Lodge", Squidward asks SpongeBob if he was dropped on his head as a baby. SpongeBob confirms it and is amazed at how Squidward found out ("Psychic powers").
- Brain damage in childhood (generally caused by traumatic brain injury or stroke) can have widely varying effects. Children are significantly more able to recover from brain damage and return to a close-to-normal level of ability than adults are since their brains are more "plastic", developing alternate pathways and repurposing other areas of the brain much more easily to fix the damaged capacity. However, since a child's brain is under heavy development, brain damage during this period can disrupt their development and result in serious developmental problems for the child. Brain damage is no laughing matter in any case (even when it Paints Smilies On Your Soul). Since the prefrontal cortex is so critical to our higher, medium, and even basic level mental processes, damage to the prefrontal cortex causes dysfunction in social, emotional, and decision-making behavior. In children, the mental repercussion can be a lot more severe, and a condition known as "acquired anti-social personality disorder" can arise from it, with the hallmarks of callousness, impulsivity, and extreme self-centered behaviour found in ASPD. The severity of this condition increases in children who get brain damage at a younger age.
- Moe Howard was dropped on his head as a toddler by his big brother Samuel, a.k.a. Shemp. (Way to go, knucklehead.) He landed on his face, damaging the nerves in his nose and eyes, and as a result, Moe was blind for almost a year.
- This trope can occur emotionally and psychologically as well as physically. The first few years of a child's life are crucial to brain development (80% of it occurs in the first five years), and if severe abuse and/or neglect occurs during this period, the child may have extreme difficulty understanding how to interact normally with others or form healthy relationships.
- A child who is severely neglected or abused during the first few years of their life is at risk for reactive attachment disorder, the symptoms of which are: 1) trying very hard to get affection from any available adult, 2) not wanting affection from anyone, and/or 3) Troubling Unchildlike Behavior such as hurting animals, violence towards other children, self-harm, etc.
- Severe, sustained neglect can permanently rob a child of their ability to speak or learn language. Danielle Crockett, discovered and rescued in July 2005, was a girl kept in a dark, filthy room by her mother for the first 7 years of her life. Although she was adopted by a loving foster family and made notable progress, she was never able to learn to speak or even communicate in any meaningful way. Another case was that of Genie, a girl whose father believed she was mentally retarded and kept her strapped to a child's toilet until she was 13. He gave her as little attention as possible, and did not talk to her or let anyone else do so, which prevented her from being able to learn any kind of language. After being rescued, she was able to learn some words and communicate non-verbally, but like Danielle she never learned to fully speak.
- 1970s punk rock groupie Nancy Spungen, girlfriend of Sid Vicious, led a short and extremely troubled life fraught with mental illness and was diagnosed with schizophrenia at 15. She screamed all the time as a baby, threw tantrums over everything as a toddler, became suicidal at 11, regularly screamed insults at and attacked her parents and siblings, tried to kill a babysitter with scissors, and got into heroin and meth as an adult. While never conclusively proven, her mother Deborah believed that Nancy’s behavior originated from her traumatic birth, when she came out severely cyanotic and nearly died of oxygen deprivation from her umbilical cord being wrapped around her neck.