Sandbox / Diagnosed by the Audience

This trope is under discussion in the Trope Repair Shop.

This character's behaviour is bizarrely outside the norm — it's way beyond mere ordinary quirkiness. No reasons are given for the strange behaviour. No specific diagnosis is ever mentioned in the story. In fact, any resemblance to any real disorder is likely accidental; the character's symptoms are exactly those symptoms the writer wants them to have. However, perhaps the audience has an idea of what disorder they have, and try their hand at diagnosing them.

A lot of mentally ill people in classical literature, especially from the 19th century and earlier, tend to not be explicitly diagnosed; psychiatry was a very young field back then (and, until a certain point in history, didn't exist at all), and so there was no manual to turn to if you wanted to give your character odd quirks. Even if an author did do the research, psychiatry has changed greatly and rapidly, meaning that their work is very likely to be invalidated by the passing of time anyway. Also, the lack of psychiatric expertise during these periods means that many historical figures might have had undiagnosed conditions (vast Wild Mass Guessing exists about this topic).

That said, No Real Life Examples, Please! We don't want to start any sessions of "armchair diagnosis" for real people, since that kind of speculation about real people inevitably leads to controversy.

Compare The Disease That Shall Not Be Named, Soap Opera Disease, Victorian Novel Disease, and G-Rated Mental Illness. The Mad Hatter, who understands himself to be insane and is largely justified in this, will usually have an ambiguous understanding of his own insanity (as opposed to having some educated self-diagnosis of schizoid personality).

For when a character is explicitly confirmed in story to have a specific disorder, but their portrayal isn't necessarily accurate, please check Hollywood Psych, Hollywood Autism, Hollywood Tourette's, "L" Is for "Dyslexia", Attention Deficit... Ooh, Shiny!, Funny Schizophrenia, and The Schizophrenia Conspiracy. When the creators say whether a character has a disorder or not outside of the work, making it no longer ambiguous in most cases, see Diagnosis of God. When the character's disorder is initially ambiguous but is confirmed later in the work, see Delayed Diagnosis. If the characters don't know what it is but the audience does, it's Disease by Any Other Name.

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Examples:

Anime & Manga (COMPLETE)

• Ah... and Mm... Are All She Says: Some fans have speculated that Toda and Tanaka are both written as autistic, which could explain Tanaka's difficulty connecting to people or showing emotion, and Toda's problems verbalizing. This offers an explanation as to why Tanaka can easily understand Toda when few others can.
• Azumanga Daioh:
  • While much of her characterization is emblematic of the cloudcuckoolander trope, Osaka is commonly headcanoned by fans as autistic as a result of how many traits of hers parallel the condition. Among other things, she displays sensory sensitivities (both seeking out and avoiding various stimuli), repeats phrases she likes, infodumps without regard for appropriateness, has odd but deep interests, and displays an unconventional perception of language (shown by her knack with wordplay and subtleties in Kanji, as well as her occasional struggles with distinguishing similar verbal concepts). She also tends to catastrophize about herself and her peers and approaches basic tasks in out-of-the-box and oftentimes counterintuitive ways.
  • Sakaki is popularly considered autistic by the manga's neurodivergent fanbase. Much of it revolves around her obsessive interest with animals, which can be easily interpreted as a special interest: it forms a large part of her daily life, tends to define her leftfield trains of thought, and ties into her tendency to worldbuild on the spot, whether it be for stuffed animals or real creatures that she encounters. Outside her interest in animals, she displays difficulty with socializing, which her peers initially misconstrue as being aloof and prickly, yet counters this with an unusually strong sense of empathy, even if it's for a cat that actively antagonizes her.
• JoJo's Bizarre Adventure: A popular theory is that Jotaro Kujo is on the autism spectrum due to his poor social skills, especially at the start of the story, as well as his official description pointing out that he acts like The Stoic because he mistakenly assumes everyone else can figure out how he's feeling.
• Keep Your Hands Off Eizouken!:
  • Midori Asakusa is commonly interpreted by fans as autistic and/or having ADHD. She's often characterized as childish, tends to get lost in fantasies, has a strong attachment to certain objects (including a stuffed rabbit that she keeps as a Security Blanket, clutching it when overwhelmed or nervous), hyperfixates on certain topics, and displays such immense difficulty with being around strangers, especially in crowded settings, that she relies on keeping her friends around her at all times when she goes out in public. It helps that author Sumito Owara has stated that he in part based Asakusa on his own experiences with autism and ADHD ^note  In an interview Japanese outlet Livedoor he stated that he has a "developmental disorder" that previously impeded his academic performance growing up, and specified on Twitter that it was a co-occurrence of autism and ADHD .
  • Tsubame Mizusaki shows several characteristics that lead fans to see her as autistic. Much of this comes from her emphasis on repetition, especially in regards to things that catch her interest, her tendency to info-dump when discussing body movements, and her fixation on character animation to the point where she gets distressed when her ability to engage in it is threatened. The fact that she displays a subdued and professional demeanor around fans, but more readily opens up when around people she considers close enough to trust is also noted as paralleling behaviors found in "neurotypical-passing" autistic individuals.
• My Hero Academia: Izuku Midoriya has many behaviors and personality quirks that lead a number of fans to headcanon him as autistic. These include an almost-obsessive focus on a singular interest (superheroes, particularly All Might, in his case) that he has devoted considerable time and energy into over the course of his life (as indicated by his myriad notebooks with detailed information and statistics on heroes), a self-admitted difficulty in understanding humor and social interaction, stimming behaviors (mild exercises, muttering to himself, and rocking in a chair as a child), a natural affinity for patterns (especially noticing them), and hyperempathy.

Comic Books (COMPLETE)

• Though Spider-Man is canonically (as far as anyone can tell), neurotypical, this Thought Slime video makes the case that the secret identity trope, particularly in how it's applied to Spider-Man, is itself an analogy for neurodivergence, and Peter's attempts to hide his inner struggles to appear "normal" can be compared to disorders like ADHD, anxiety, autism, and a number of others.

Films — Animation (COMPLETE)

• Among neurodivergent fans of Lilo & Stitch, Lilo herself is frequently interpreted as being autistic, due to her difficulties with socializing, her niche and unusually strong interests (e.g. Elvis Presley and photographing fat people), and her character arc of seeking acceptance among peers and family members who don't fully understand how she thinks and acts. This interpretation is so popular that Lilo has ended up becoming a makeshift mascot for various "autistic headcanon" blogs.

Films — Live-Action (COMPLETE)

• There have been numerous psychiatrists speculating about Anakin Skywalker and trying to form a diagnosis based on the symptoms he shows in the Star Wars prequels, with the most popular theory being Borderline Personality Disorder. Likewise, in The Force Awakens, his successor and grandson Kylo Ren shows a similar collection of huge mood swings, extreme outbursts of anger, lack of empathy, difficulties with interpersonal relationships, emotional disturbances, and odd obsessions and anxieties. It doesn't help matters that in Star Wars Legends it's shown that being Drunk on the Dark Side has similar effects to hard drugs on brain chemistry.

Live-Action TV (COMPLETE)

• The Big Bang Theory: While Jim Parsons confirmed that he portrayed Sheldon as an autistic character, no conformation exists for his Distaff Counterpart and girlfriend, Amy. Despite this, Amy is often described by audiences as an autistic-coded character, thanks to her carrying over Sheldon's lack of social skills, niche interests, and idiosyncratic lines of thought that allow her to get along with Sheldon to a greater degree than the rest of his peer group. Her social anxiety and its roots in her lifelong inability to "click" with most other people are also noted as resonating strongly with real-world autistic experiences.
• Gordon Brittas of The Brittas Empire acts in a way that has led some of the audience to theorize that he's on the Autism Spectrum, having a severe deficit of social skills, being absolutely confused at the concept of subtext (something which Laura attempts to, but fails to explain to him) let alone sarcasm, and having a very rule-bound and routine-heavy attitude towards his job, to the point that people have been driven insane because he wouldn't accommodate their desired changes. He also has a lack of regard for privacy, at one point spying on his staff without it ever occurring to him that this may not be socially acceptable, and has a tendency to make exaggerated arm gestures and shake his head when he speaks. One of the co-creators (Andrew Norriss) reposted a blog post from a watcher theorizing this on his website, suggesting possible Diagnosis of God, but there is no concrete evidence otherwise and certainly not within the show itself.

• The incarnation of Morse in Endeavour is interpreted by many in the fanbase to be neurodivergent in some capacity, as he displays a propensity to addiction, a history of suicide attempts, depressive moods, savant qualities with regards to literature and opera, and particularly in early seasons a lack of social skills and seemingly unconscious recklessness.

Video Games (COMPLETE)

• Cookie Run: Kingdom: Eclair Cookie's narrow interests, tendency to overshare and infodump, and Innocently Insensitive moments all lead to neurodivergent fans commonly headcanoning him as autistic.
• Deltarune: A sizable chunk of fans headcanon Kris as autistic. This interpretation runs mainly off of a combination of their aloofness and disconnect from their peers as the only human in a town of monsters, which is easy to read as an allegory for being neurodivergent in an otherwise neurotypical social environment, their Heroic Mime status, which resonates well with nonverbal and semi-verbal autistic fans, and their surprisingly in-depth enthusiasm for odd, niche subjects, which parallel autistic special interests.
• Octopath Traveler: A number of fans interpret Olberic, Primrose and Therion as suffering from post-traumatic stress disorder. Olberic and Primrose both have frequent nightmares of Hornburg's ruin and murder of Geoffrey Azelhart, respectively. While Olberic was accepted into Cobbleston and treated kindly by its people, Primrose crossed the Despair Event Horizon and says several times that murdering the three men who murdered her father is her only reason for living, voluntarily subjecting herself to Helgenish's mistreatment for years for the mere chance at revenge. Therion, meanwhile, has several flashbacks of his partnership with Darius, and has severe trust issues after being cruelly betrayed and nearly murdered by him.
• Pico: In fanworks, Pico is often depicted as suffering from PTSD following the events of Pico's School, sometimes extended to include his other troubling childhood misadventures. The only disorder he "canonically" has is schizophrenia, though even that is up in the air due to coming from a long-defunct site and Pico's own status as an Interpretative Character.
• Pokémon:
  • ''Pokémon Ruby and Sapphire: Some fans have theorized that Courtney might be on the autism spectrum, as she is highly intelligent, rarely speaks, and is disinterested in most people and things except for a few special interests.
  • Pokémon Diamond and Pearl: A large portion of the fandom sees Barry as having ADHD, due him being impulsive, easily distracted, incredibly impatient, and hyperactive, among other things.
• Splatoon 3: Many fans have taken Harmony's odd, awkward mannerisms (such as her stilted speech, obliviousness towards her clownfish companion, and her seemingly stimming with an Ultra Hand-like grabber toy) as evidence of some sort of neurodivergence, like autism or ADHD.
• Undertale:
  • A sizable contingency of fans headcanon Papyrus as autistic. Much of this stems from his Socially Awkward Hero status (to the point where he needs a guide book to know how to act during a date), his tendency to interpret insults towards him as compliments or self-insults, his occasional "childish" behaviors, and especially his deep interests in cooking spaghetti and making puzzles, the latter of which defines a good chunk of his life (and consequently is easy to read as a special interest).
  • While it's never openly stated in-game, Sans' laziness and apathy to almost everything around him other than Papyrus led to a huge portion of the game's fanbase interpreting him as chronically depressed. This is especially true when considering his dialogue during the final battles of both the Pacifist and Genocide routes, which characterize him as having given up in life a long time ago. The latter fight in particular resulted in no shortage of fanfics that emphasized the interpretation of him as depressed.
  • There's a popular headcanon of Frisk being selectively mute, due to them staying silent for most of the game and only speaking when they initiate the conversation or are directly asked a question.

Web Animation (COMPLETE)

• Mystery Skulls Animated: Arthur is commonly headcanoned as having depression and PTSD following the cave incident due to his fear of Mystery (who ripped off his arm to save him) and complete neglect of his own wellbeing during his search for Lewis, going days without eating or sleeping at a time according to Losing My Mind.
• Spooky Month:
  • Fans commonly headcanon Skid and Pump as having ADHD and/or autism, from their hyperactive personalities and easily trusting nature even towards Obviously Evil people. Their obsession with Spooky Month, to the point they constantly wear Halloween costumes months away from October, is also easily readable as a special interest.
  • Pump having mild pyromania is very common in fanworks, due to his comment about wanting to burn the Happy Fella "to see it if it screams".
  • Robert is interpreted as neurodivergent, due to him stimming while talking about the Happy Fella in "Unwanted Guest".

Western Animation (COMPLETE)

• SpongeBob SquarePants: All three members of the show's main trio are commonly headcanoned as autistic:
  • The title character SpongeBob is a Manchild who is utterly obsessed with working at the Krusty Krab (one episode has him going crazy when he's forced to take a vacation), and has encyclopedic interests in other niche fields such as jellyfishing and bubble-blowing, and despite having the knowledge necessary to drive, he can't do it because he gets too nervous when he's behind the wheel, a fear that many autistic people can relate to.
  • Patrick shares SpongeBob's youthful personality and interests in jellyfishing and bubble-blowing, in addition to being not too bright with occasional moments of genius and clarity, and a creative spark at times.
  • Squidward expresses a deep interest in fine art, makes particular gestures in particular emotional settings that autistic fans commonly interpret as stims, and personality-wise stands in the opposite extreme from SpongeBob and Patrick's more goofy and jovial demeanor, exemplifying the "professorial" archetype of autism.
• Star vs. the Forces of Evil: Star Butterfly is prone to "stimming" behaviors like bouncing up and down or chewing on her wand, tends to be easily distracted, is frequently Literal-Minded, and has poor social skills (like having No Sense of Personal Space). She gets a bit better on all these points along with Character Development, though the behaviors don't entirely go away. As a result, many fans headcanon her as autistic and/or having ADHD.
• Steven Universe: The Movie:
  • Many fans have speculated that Spinel has Borderline Personality Disorder, with features of all the subtypes: a fear of abandonment that persisted even after her memories were erased, intense anger at those around her, including those who personally did her no wrong, and wildly shifting moods and opinions. Most tellingly is by her own admission at the end of the movie that she has no real idea why she wants to hurt Steven as bad as she does.
  • Many neurodivergent viewers see rejuvenated Amethyst's Baby See, Baby Do moments as being reminiscent of echolalia.

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