Speech

Speech is the vocalized form of human communication. It is based upon the syntactic combination of items drawn from the lexicon. 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 many thousands of different, and mutually unintelligible, human languages.

Overview

Speech in some cultures has become the basis for written language, often leading to the development of an alphabet. Two of the most fundamental questions about speech are: "what is the nature of the cognitive processes that convert the incoming acoustic signal into a form useful for comprehension?" and "what set of processes and cognitive structures are responsible for the production of speech?"

Speech production

Speech production is a multi-step process by which thoughts are generated into spoken utterances. Production involves the selection of appropriate words and the appropriate form of those words from the lexicon and morphology, and the organization of those words through the syntax. In addition, the phonetics and phonology determine the sounds that are made and the rhythm, stress, and intonation of speech.

Speech perception

Speech perception refers to the processes by which humans can interpret and understand the sounds used in language. The study of speech perception is closely linked to the fields of phonetics and phonology in linguistics and cognitive psychology and perception in psychology. Research in speech perception seeks to understand how human listeners recognize speech sounds and use this information to understand spoken language.

Speech disorders

There are several organic and psychological factors that can affect speech. Among these are:

• Diseases and disorders of the lungs or the vocal cords, including paralysis, respiratory infections, and cancers of the lungs and throat.
• Dysarthria, which is characterized by slow or slurred speech due to weakness or difficulty moving the muscles used for speech production.
• Aphasia, a language disorder that affects a person's ability to communicate.
• Stuttering, a speech disorder characterized by repetition of sounds, syllables, or words; prolongation of sounds; and interruptions in speech.

See also

• Language
• Linguistics
• Phonetics
• Phonology
• Speech-language pathology

Speech

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  Real-time MRI of speaking in English
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  Diagram of places of articulation
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  Diagram of Broca's and Wernicke's areas in the brain