Speech is the vocalized form of human communication. It is based upon the syntactic combination of lexicals and names that are drawn from very large (usually about 10,000 different words) vocabularies. Each spoken word is created out of the phonetic combination of a limited set of vowel and consonant speech sound units. These vocabularies, the syntax which structures them, and their set of speech sound units differ, creating the existence of many thousands of different types of mutually unintelligible human languages. Most human speakers (polyglots) are able to communicate in two or more of them. The vocal abilities that enable humans to produce speech also provide humans with the ability to sing.
A gestural form of human communication exists for the deaf in the form of sign language. Speech in some cultures has become the basis of a written language, often one that differs in its vocabulary, syntax and phonetics from its associated spoken one, a situation called diglossia. Speech in addition to its use in communication, it is suggested by some psychologists such as Vygotsky is internally used by mental processes to enhance and organize cognition in the form of an interior monologue.
Speech is researched in terms of the speech production and speech perception of the sounds used in vocal language. Other research topics concern speech repetition, the ability to map heard spoken words into the vocalizations needed to recreated that plays a key role in the vocabulary expansion in children and speech errors. Several academic disciplines study these including acoustics, psychology, speech pathology, linguistics, cognitive science, communication studies, otolaryngology and computer science. Another area of research is how the human brain in its different areas such as the Broca's area and Wernicke's area underlies speech.
It is controversial how far human speech is unique in that other animals also communicate with vocalizations. While none in the wild have compatibly large vocabularies, research upon the nonverbal abilities of language trained apes such as Washoe and Kanzi raises the possibility that they might have these capabilities. The origins of speech are unknown and subject to much debate and speculation.
Famous quotes containing the word speech:
“He gave man speech, and speech created thought,
Which is the measure of the universe;”
—Percy Bysshe Shelley (17921822)
“A society in which adults are estranged from the world of children, and often from their own childhood, tends to hear childrens speech only as a foreign language, or as a lie.... Children have been treated ... as congenital fibbers, fakers and fantasisers.”
—Beatrix Campbell (b. 1947)
“We hear about constitutional rights, free speech and the free press. Every time I hear those words I say to myself, That man is a Red, that man is a Communist. You never heard a real American talk in that manner.”
—Frank Hague (18761956)