A word salad is a "confused or unintelligible mixture of seemingly random words and phrases",[1] most often used to describe a symptom of a neurological or mental disorder. The name schizophasia is used in particular to describe the confused language that may be evident in schizophrenia.[2] The words may or may not be grammatically correct, but they are semantically confused to the point that the listener cannot extract any meaning from them. The term is often used in psychiatry as well as in theoretical linguistics to describe a type of grammatical acceptability judgement by native speakers, and in computer programming to describe textual randomization.
Word salad may describe a symptom of neurological or psychiatric conditions in which a person attempts to communicate an idea, but words and phrases that may appear to be random and unrelated come out in an incoherent sequence instead. Often, the person is unaware that they did not make sense. It appears in people with dementia and schizophrenia,[3] as well as after anoxic brain injury. In schizophrenia, it is called schizophasia. Clang associations are especially characteristic of mania, as seen in bipolar disorder, as a somewhat more severe variation of flight of ideas. In extreme mania, the patient's speech may become incoherent, with associations markedly loosened, thus presenting as a veritable word salad.
It may be present as:
Word salad can be generated by a computer program for entertainment purposes by inserting randomly chosen words of the same type (nouns, adjectives, etc.) into template sentences with missing words, a game similar to Mad Libs. The video game company Maxis, in their seminal SimCity 2000, used this technique to create an in-game "newspaper" for entertainment; the columns were composed by taking a vague story-structure, and using randomization, inserted various nouns, adjectives, and verbs to generate seemingly unique stories.
Another way of generating meaningless text is mojibake, also called ("letter salad") in German, in which an assortment of seemingly random text is generated through character encoding incompatibility in which characters in one set are replaced by those of another. The effect is more effective in languages where each character represents a word, such as Chinese.
More serious attempts to automatically produce nonsense stem from Claude Shannon's seminal paper A Mathematical Theory of Communication from 1948[6] in which progressively more convincing nonsense is generated first by choosing letters and spaces randomly, then according to the frequency with which each character appears in some sample of text, then respecting the likelihood that the chosen letter appears after the preceding one or two in the sample text, and then applying similar techniques to whole words. Its most convincing nonsense is generated by second-order word approximation, in which words are chosen by a random function weighted to the likelihood that each word follows the preceding one in normal text:
Markov chains can be used to generate random but somewhat human-looking sentences. This is used in some chat-bots, especially on IRC networks.
Nonsensical phrasing can also be generated for more malicious reasons, such as the Bayesian poisoning used to counter Bayesian spam filters by using a string of words which have a high probability of being collocated in English, but with no concern for whether the sentence makes sense grammatically or logically.