Speech repetition
Encyclopedia
Speech repetition is the saying
by one individual of the spoken vocalizations
made by another individual. This requires the ability in the person making the copy to map the sensory input they hear
from the other person's vocal pronunciation
into a similar motor output with their own vocal tract
.
Such speech input output imitation often occurs independently of speech comprehension such as in speech shadowing
when a person automatically says words heard in earphones, and the pathological condition of echolalia
in which people reflex
ively repeat overheard words. This links to speech repetition of words being separate in the brain
to speech perception
. Speech repetition occurs in the dorsal speech processing stream while speech perception occurs in the ventral speech processing stream. Repetitions are often incorporated unawares by this route into spontaneous novel sentences immediately or after delay following storage in phonological memory.
In humans, the ability to map heard input vocalizations into motor output is highly developed due to this copying ability playing a critical role in a child's rapid expansion of their spoken vocabulary. In older children and adults it still remains important as it enables the continued learning of novel words and names and additional languages
. Such repetition is also necessary for the propagation of language from generation to generation. It has also been suggested that the phonetic units out of which speech is made have been selected upon by the process of vocabulary expansion and vocabulary transmissions due to children preferentially copying words in terms of more easily imitated elementary units.
s both in normals (during speech shadowing
and during echolalia
by retarded individual
s. The imitation of speech syllables possibly happens even quicker: people begin imitating the second phone in the syllable [ao] earlier than they can identify it (out of the set [ao], [aæ] and [ai]. Indeed, "...simply executing a shift to [o] upon detection of a second vowel in [ao] takes very little longer than does interpreting and executing it as a shadowed response". Neurobiologically this suggests "...that the early phases of speech analysis yield information which is directly convertible to information required for speech production". Vocal repetition can be done immediately as in speech shadowing and echolalia. It can also be done after the pattern of pronunciation is stored in short-term memory
or long-term memory
. It automatically uses both auditory and where available visual information about how a word is produced.
The automatic nature of speech repetition was noted by Carl Wernicke, the late nineteenth century neurologist
, who observed that “The primary speech movements, enacted before the development of consciousness, are reflexive and mimicking in nature..”.
before speech comprehension and also babbling
: 18 week-old infants spontaneously copy vocal expressions provided the accompanying voice matches. Imitation of vowels has been found as young as 12 weeks. It is independent of native language, language skills, word comprehension and a speaker's intelligence
. Many autistic
and some mentally retarded
people engage in the echolalia of overheard words (often their only vocal interaction with others) without understanding what they echo. Reflex uncontrolled echoing of others words and sentences occurs in roughly half of those with Gilles de la Tourette syndrome. The ability to repeat words and nonwords without comprehension also occurs in mixed transcortical aphasia
where it links to the sparing of the short-term phonological store.
The ability to repeat and imitate speech sounds occurs separately to that of normal speech. Speech shadowing provides evidence of a 'privileged' input/output speech loop that is distinct to the other components of the speech system. Neurocognitive
research likewise finds evidence of a direct (nonlexical) link between phonological analysis input and motor programming output.
, age
and individual anatomical variability. Such variability is extensive making input output mapping of speech more complex than a simple mapping of vocal track movements. The shape of the mouth varies widely: dentist
s recognize three basic shapes of palate
: trapezoid, ovoid, and triagonal; six types of malocclusion
between the two jaw
s; nine ways teeth relate to the dental arch and a wide range of maxilla
ry and mandible deformities. Vocal sound can also vary due to dental injury and dental caries
. Other factors that do not impede the sensory motor mapping needed for vocal imitation are gross oral deformations such as hair-lips, cleft palates or amputations of the tongue tip, pipe smoking, pencil biting and teeth clinching (such as in ventriloquism
). Paranasal sinuses vary between individuals 20-fold in volume, and differ in the presence and the degree of their asymmetry.
s that differ in thirteen imitable vocal tract place of articulation
s (from the lip
s to the glottis
). These phones can potentially be pronounced with eleven types of imitable manner of articulation
s (nasal
s to lateral clicks). Speech can be copied in regard to its social accent, intonation
, pitch
and individuality (as with entertainment impersonator
s). Speech can be articulated in ways which diverge considerably in speed, timbre
, pitch, loudness
and emotion
. Speech further exists in different forms such as song
, verse
, scream and whisper
. Intelligible speech can be produced with pragmatic intonation and in regional dialects and foreign accent
s. These aspects are readily copied: people asked to repeat speech-like words imitate not only phones but also accurately other pronunciation aspects such as fundamental frequency
, schwa
-syllable expression, voice spectra
and lip kinematics, voice onset time
s, and regional accent.
. A study of 17,000 one and two word utterances made by six children between 18 months to 25 months found that, depending upon the particular infant
, between 5% and 45% of their words might be mimicked. These figures are minima since they concern only immediately heard words. Many words that may seem spontaneous are in fact delayed imitations heard days or weeks previously. At 13 months children who imitate new words (but not ones they already know) show a greater increase in noun
vocabulary at four months and non noun vocabulary at eight months. A major predictor of vocabulary increase in both 20 months, 24 months, and older children between 4 and 8 years is their skill in repeating nonword phone sequences (a measure of mimicry and storage). This is also the case with children with Downs syndrome . The effect is larger than even age: in a study of 222 two year old children that had spoken vocabularies ranging between 3–601 words the ability to repeat nonwords accounted for 24% of the variance
compared to 15% for age and 6% for gender
(girls better than boys).
, pronunciation patterns
, and conversational pragmatics
of speech by making monologue
s (often in crib talk
) in which they repeat and manipulate in word play
phrases and sentences previously overheard. Many proto-conversations involve children (and parents) repeating what each other has said in order to sustain social and linguistic interaction. It has been suggested that the conversion of speech sound into motor responses helps aid the vocal “alignment of interactions” by “coordinating the rhythm and melody of their speech”. Repetition enables immigrant monolingual children to learn a second language by allowing them to take part in 'conversations'. Imitation related processes aids the storage of overheard words by putting them into speech based short- and long-term memory.
performed better in short-term memory tasks such as repeating nonword vocalizations compared to nonpolyglots though both are otherwise similar in general intelligence, visuo-spatial short-term memory and paired-associate learning ability. Language delay
in contrast links to impairments in vocal imitation.
research upon the human brain finds that 81% of areas that show disruption of phone identification are also those in which the imitating of oral movements is disrupted and vice versa; Brain injuries
in the speech areas show a 0.9 correlation between those causing impairments to the copying of oral movements and those impairing phone production and perception.
, onto frontal motor areas, and is not normally involved in speech perception.
Carl Wernicke identified a pathway between the left posterior superior temporal sulcus
(a cerebral cortex region sometimes called the Wernicke's area
) as a centre of the sound “images” of speech and its syllables that connected through the arcuate fasciculus
with part of the inferior frontal gyrus
(sometimes called the Broca's area
) responsible for their articulation. This pathway is now broadly identified as the dorsal speech pathway, one of the two pathways (together with the ventral pathway) that process speech. The posterior superior temporal gyrus
is specialized for the transient representation of the phonetic sequences used for vocal repetition. Part of the auditory cortex also can represent aspects of speech such as its consonantal features.
s have been identified that both process the perception and production of motor movements. This is done not in terms of their exact motor performance but an inference of the intended motor goals with which it is organized. Mirror neurons that both perceive and produce the motor movements of speech have been identified. According to the motor theory of speech imitation such speech mirror neurons in infants have selected for motor goals with vocal track gestures that are easy to imitate and this has shaped the nature of the phonetic units out of which spoken words are constructed. Speech is mirrored constantly into its articulations since speakers cannot know in advance that a word is unfamiliar and in need of repetition—which is only learnt after the opportunity to map it into articulations has gone. Thus, speakers if they are to incorporate unfamiliar words into their spoken vocabulary
must by default map all spoken input. The motor theory of speech imitation unlike that of motor theory of speech perception
does not link mirror neurons with speech perception
.
moreover underlies the evolved nature of the vowel
and consonant units of phonetics.
s learn their songs from those made by other birds. In several examples, birds show highly developed repetition abilities: the Sri Lankan greater Greater Racket-tailed Drongo
(Dicrurus paradiseus) copies the calls of predators and the alarm signals of other birds Albert's Lyrebird
(Menura alberti) can accurately imitate the Satin Bowerbird
(Ptilonorhynchus violaceus),
Research upon avian vocal motor neurons finds that they perceive their song as a series of articulatory gestures as in humans. Birds that can imitate humans, such as the Indian Hill myna
(Gracula religiosa), imitate human speech by mimicking the various speech formants, created by changing the shape of the human vocal tract, with different vibration frequencies of its internal tympaniform membrane
. Indian hill mynahs also imitate such phonetic characteristics as voicing
, fundamental frequencies
, formant transition
s, nasalization
, and timing, through their vocal movements are made in a different way from those of the human vocal apparatus.
show an ability to imitate language signs with chimpanzee
s such as Washoe
who was able to learn with his arms a vocabularly of 250 American Sign Language
gestures. However, such human trained apes show no ability to imitate human speech vocalizations.
Speech
Speech is the human faculty of speaking.It may also refer to:* Public speaking, the process of speaking to a group of people* Manner of articulation, how the body parts involved in making speech are manipulated...
by one individual of the spoken vocalizations
Speech production
Speech production is the process by which spoken words are selected to be produced, have their phonetics formulated and then finally are articulated by the motor system in the vocal apparatus...
made by another individual. This requires the ability in the person making the copy to map the sensory input they hear
Hearing (sense)
Hearing is the ability to perceive sound by detecting vibrations through an organ such as the ear. It is one of the traditional five senses...
from the other person's vocal pronunciation
Pronunciation
Pronunciation refers to the way a word or a language is spoken, or the manner in which someone utters a word. If one is said to have "correct pronunciation", then it refers to both within a particular dialect....
into a similar motor output with their own vocal tract
Vocal tract
The vocal tract is the cavity in human beings and in animals where sound that is produced at the sound source is filtered....
.
Such speech input output imitation often occurs independently of speech comprehension such as in speech shadowing
Speech shadowing
Speech shadowing is an experimental technique in which subjects repeat speech immediately after hearing it . The reaction time between hearing a word and pronouncing it can be as short as 254 ms or even 150 ms. This is only the delay duration of a speech syllable...
when a person automatically says words heard in earphones, and the pathological condition of echolalia
Echolalia
Echolalia is the automatic repetition of vocalizations made by another person. It is closely related to echopraxia, the automatic repetition of movements made by another person....
in which people reflex
Reflex
A reflex action, also known as a reflex, is an involuntary and nearly instantaneous movement in response to a stimulus. A true reflex is a behavior which is mediated via the reflex arc; this does not apply to casual uses of the term 'reflex'.-See also:...
ively repeat overheard words. This links to speech repetition of words being separate in the brain
Human brain
The human brain has the same general structure as the brains of other mammals, but is over three times larger than the brain of a typical mammal with an equivalent body size. Estimates for the number of neurons in the human brain range from 80 to 120 billion...
to speech perception
Speech perception
Speech perception is the process by which the sounds of language are heard, interpreted and understood. The study of speech perception is closely linked to the fields of phonetics and phonology in linguistics and cognitive psychology and perception in psychology...
. Speech repetition occurs in the dorsal speech processing stream while speech perception occurs in the ventral speech processing stream. Repetitions are often incorporated unawares by this route into spontaneous novel sentences immediately or after delay following storage in phonological memory.
In humans, the ability to map heard input vocalizations into motor output is highly developed due to this copying ability playing a critical role in a child's rapid expansion of their spoken vocabulary. In older children and adults it still remains important as it enables the continued learning of novel words and names and additional languages
Second language acquisition
Second-language acquisition or second-language learning is the process by which people learn a second language. Second-language acquisition is also the name of the scientific discipline devoted to studying that process...
. Such repetition is also necessary for the propagation of language from generation to generation. It has also been suggested that the phonetic units out of which speech is made have been selected upon by the process of vocabulary expansion and vocabulary transmissions due to children preferentially copying words in terms of more easily imitated elementary units.
Automatic
Vocal imitation happens quickly: words can be repeated within 250-300 millisecondMillisecond
A millisecond is a thousandth of a second.10 milliseconds are called a centisecond....
s both in normals (during speech shadowing
Speech shadowing
Speech shadowing is an experimental technique in which subjects repeat speech immediately after hearing it . The reaction time between hearing a word and pronouncing it can be as short as 254 ms or even 150 ms. This is only the delay duration of a speech syllable...
and during echolalia
Echolalia
Echolalia is the automatic repetition of vocalizations made by another person. It is closely related to echopraxia, the automatic repetition of movements made by another person....
by retarded individual
Mental retardation
Mental retardation is a generalized disorder appearing before adulthood, characterized by significantly impaired cognitive functioning and deficits in two or more adaptive behaviors...
s. The imitation of speech syllables possibly happens even quicker: people begin imitating the second phone in the syllable [ao] earlier than they can identify it (out of the set [ao], [aæ] and [ai]. Indeed, "...simply executing a shift to [o] upon detection of a second vowel in [ao] takes very little longer than does interpreting and executing it as a shadowed response". Neurobiologically this suggests "...that the early phases of speech analysis yield information which is directly convertible to information required for speech production". Vocal repetition can be done immediately as in speech shadowing and echolalia. It can also be done after the pattern of pronunciation is stored in short-term memory
Short-term memory
Short-term memory is the capacity for holding a small amount of information in mind in an active, readily available state for a short period of time. The duration of short-term memory is believed to be in the order of seconds. A commonly cited capacity is 7 ± 2 elements...
or long-term memory
Long-term memory
Long-term memory is memory in which associations among items are stored, as part of the theory of a dual-store memory model. According to the theory, long term memory differs structurally and functionally from working memory or short-term memory, which ostensibly stores items for only around 20–30...
. It automatically uses both auditory and where available visual information about how a word is produced.
The automatic nature of speech repetition was noted by Carl Wernicke, the late nineteenth century neurologist
Neurologist
A neurologist is a physician who specializes in neurology, and is trained to investigate, or diagnose and treat neurological disorders.Neurology is the medical specialty related to the human nervous system. The nervous system encompasses the brain, spinal cord, and peripheral nerves. A specialist...
, who observed that “The primary speech movements, enacted before the development of consciousness, are reflexive and mimicking in nature..”.
Independent of speech
Vocal imitiation arises in developmentChild development
Child development stages describe theoretical milestones of child development. Many stage models of development have been proposed, used as working concepts and in some cases asserted as nativist theories....
before speech comprehension and also babbling
Babbling
Babbling is a stage in child development and a state in language acquisition, during which an infant appears to be experimenting with uttering sounds of language, but not yet producing any recognizable words...
: 18 week-old infants spontaneously copy vocal expressions provided the accompanying voice matches. Imitation of vowels has been found as young as 12 weeks. It is independent of native language, language skills, word comprehension and a speaker's intelligence
Intelligence
Intelligence has been defined in different ways, including the abilities for abstract thought, understanding, communication, reasoning, learning, planning, emotional intelligence and problem solving....
. Many autistic
Autism
Autism is a disorder of neural development characterized by impaired social interaction and communication, and by restricted and repetitive behavior. These signs all begin before a child is three years old. Autism affects information processing in the brain by altering how nerve cells and their...
and some mentally retarded
Mental retardation
Mental retardation is a generalized disorder appearing before adulthood, characterized by significantly impaired cognitive functioning and deficits in two or more adaptive behaviors...
people engage in the echolalia of overheard words (often their only vocal interaction with others) without understanding what they echo. Reflex uncontrolled echoing of others words and sentences occurs in roughly half of those with Gilles de la Tourette syndrome. The ability to repeat words and nonwords without comprehension also occurs in mixed transcortical aphasia
Mixed transcortical aphasia
Mixed transcortical aphasia is the least common of the three transcortical aphasias . Mixed transcortical aphasia is characterized by severe speaking and comprehension impairment, but with preserved repetition...
where it links to the sparing of the short-term phonological store.
The ability to repeat and imitate speech sounds occurs separately to that of normal speech. Speech shadowing provides evidence of a 'privileged' input/output speech loop that is distinct to the other components of the speech system. Neurocognitive
Neurocognitive
Neurocognitive is a term used to describe cognitive functions closely linked to the function of particular areas, neural pathways, or cortical networks in the brain substrate layers of neurological matrix at the cellular molecular level...
research likewise finds evidence of a direct (nonlexical) link between phonological analysis input and motor programming output.
Effector independent
Speech sounds can be imitatively mapped into vocal articulations in spite of vocal tract anatomy differences in size and shape due to genderGender
Gender is a range of characteristics used to distinguish between males and females, particularly in the cases of men and women and the masculine and feminine attributes assigned to them. Depending on the context, the discriminating characteristics vary from sex to social role to gender identity...
, age
Human development (biology)
Human development is the process of growing to maturity. In biological terms, this entails growth from a one-celled zygote to an adult human being.- Biological development:...
and individual anatomical variability. Such variability is extensive making input output mapping of speech more complex than a simple mapping of vocal track movements. The shape of the mouth varies widely: dentist
Dentist
A dentist, also known as a 'dental surgeon', is a doctor that specializes in the diagnosis, prevention, and treatment of diseases and conditions of the oral cavity. The dentist's supporting team aides in providing oral health services...
s recognize three basic shapes of palate
Palate
The palate is the roof of the mouth in humans and other mammals. It separates the oral cavity from the nasal cavity. A similar structure is found in crocodilians, but, in most other tetrapods, the oral and nasal cavities are not truly separate. The palate is divided into two parts, the anterior...
: trapezoid, ovoid, and triagonal; six types of malocclusion
Malocclusion
A malocclusion is a misalignment of teeth or incorrect relation between the teeth of the two dental arches. The term was coined by Edward Angle, the "father of modern orthodontics", as a derivative of occlusion, which refers to the manner in which opposing teeth meet.-Presentation:Most people have...
between the two jaw
Jaw
The jaw is any opposable articulated structure at the entrance of the mouth, typically used for grasping and manipulating food. The term jaws is also broadly applied to the whole of the structures constituting the vault of the mouth and serving to open and close it and is part of the body plan of...
s; nine ways teeth relate to the dental arch and a wide range of maxilla
Maxilla
The maxilla is a fusion of two bones along the palatal fissure that form the upper jaw. This is similar to the mandible , which is also a fusion of two halves at the mental symphysis. Sometimes The maxilla (plural: maxillae) is a fusion of two bones along the palatal fissure that form the upper...
ry and mandible deformities. Vocal sound can also vary due to dental injury and dental caries
Dental caries
Dental caries, also known as tooth decay or a cavity, is an irreversible infection usually bacterial in origin that causes demineralization of the hard tissues and destruction of the organic matter of the tooth, usually by production of acid by hydrolysis of the food debris accumulated on the...
. Other factors that do not impede the sensory motor mapping needed for vocal imitation are gross oral deformations such as hair-lips, cleft palates or amputations of the tongue tip, pipe smoking, pencil biting and teeth clinching (such as in ventriloquism
Ventriloquism
Ventriloquism, or ventriloquy, is an act of stagecraft in which a person manipulates his or her voice so that it appears that the voice is coming from elsewhere, usually a puppeteered "dummy"...
). Paranasal sinuses vary between individuals 20-fold in volume, and differ in the presence and the degree of their asymmetry.
Diverse linguistic vocalizations
Vocal imitation occurs potentially in regard to a diverse range of phonetic units and types of vocalization. The world's languages use consonantal phoneConsonant
In articulatory phonetics, a consonant is a speech sound that is articulated with complete or partial closure of the vocal tract. Examples are , pronounced with the lips; , pronounced with the front of the tongue; , pronounced with the back of the tongue; , pronounced in the throat; and ,...
s that differ in thirteen imitable vocal tract place of articulation
Place of articulation
In articulatory phonetics, the place of articulation of a consonant is the point of contact where an obstruction occurs in the vocal tract between an articulatory gesture, an active articulator , and a passive location...
s (from the lip
Lip
Lips are a visible body part at the mouth of humans and many animals. Lips are soft, movable, and serve as the opening for food intake and in the articulation of sound and speech...
s to the glottis
Glottis
The glottis is defined as the combination of the vocal folds and the space in between the folds .-Function:...
). These phones can potentially be pronounced with eleven types of imitable manner of articulation
Manner of articulation
In linguistics, manner of articulation describes how the tongue, lips, jaw, and other speech organs are involved in making a sound. Often the concept is only used for the production of consonants, even though the movement of the articulars will also greatly alter the resonant properties of the...
s (nasal
Nasal consonant
A nasal consonant is a type of consonant produced with a lowered velum in the mouth, allowing air to escape freely through the nose. Examples of nasal consonants in English are and , in words such as nose and mouth.- Definition :...
s to lateral clicks). Speech can be copied in regard to its social accent, intonation
Intonation
Intonation may refer to:*Intonation , the variation of tone used when speaking*Intonation , a musician's realization of pitch accuracy, or the pitch accuracy of a musical instrument*Intonation Music Festival, held in Chicago...
, pitch
Pitch accent
Pitch accent is a linguistic term of convenience for a variety of restricted tone systems that use variations in pitch to give prominence to a syllable or mora within a word. The placement of this tone or the way it is realized can give different meanings to otherwise similar words...
and individuality (as with entertainment impersonator
Impersonator
An impersonator is someone who imitates or copies the behavior or actions of another. There are many reasons for someone to be an impersonator, some common ones being as follows:...
s). Speech can be articulated in ways which diverge considerably in speed, timbre
Timbre
In music, timbre is the quality of a musical note or sound or tone that distinguishes different types of sound production, such as voices and musical instruments, such as string instruments, wind instruments, and percussion instruments. The physical characteristics of sound that determine the...
, pitch, loudness
Loudness
Loudness is the quality of a sound that is primarily a psychological correlate of physical strength . More formally, it is defined as "that attribute of auditory sensation in terms of which sounds can be ordered on a scale extending from quiet to loud."Loudness, a subjective measure, is often...
and emotion
Emotion
Emotion is a complex psychophysiological experience of an individual's state of mind as interacting with biochemical and environmental influences. In humans, emotion fundamentally involves "physiological arousal, expressive behaviors, and conscious experience." Emotion is associated with mood,...
. Speech further exists in different forms such as song
Song
In music, a song is a composition for voice or voices, performed by singing.A song may be accompanied by musical instruments, or it may be unaccompanied, as in the case of a cappella songs...
, verse
Poetry
Poetry is a form of literary art in which language is used for its aesthetic and evocative qualities in addition to, or in lieu of, its apparent meaning...
, scream and whisper
Whispering
Whispering is an unvoiced mode of phonation in which the vocal cords do not vibrate normally but are instead adducted sufficiently to create audible turbulence as the speaker exhales during speech. This is a somewhat greater adduction than that found in breathy voice...
. Intelligible speech can be produced with pragmatic intonation and in regional dialects and foreign accent
Foreign accent
Foreign accent may refer to:*accent *diacritic, an accent mark in writing*non-native pronunciations of English*Anglophone pronunciation of foreign languages...
s. These aspects are readily copied: people asked to repeat speech-like words imitate not only phones but also accurately other pronunciation aspects such as fundamental frequency
Fundamental frequency
The fundamental frequency, often referred to simply as the fundamental and abbreviated f0, is defined as the lowest frequency of a periodic waveform. In terms of a superposition of sinusoids The fundamental frequency, often referred to simply as the fundamental and abbreviated f0, is defined as the...
, schwa
Schwa
In linguistics, specifically phonetics and phonology, schwa can mean the following:*An unstressed and toneless neutral vowel sound in some languages, often but not necessarily a mid-central vowel...
-syllable expression, voice spectra
Spectra
Spectra are conditions or values that vary over a continuum.Spectra may also refer to:* Kia Spectra, a car developed by Kia Motors from 2000-present* Optare Spectra, a bus body built by Optare...
and lip kinematics, voice onset time
Voice onset time
In phonetics, voice onset time, commonly abbreviated VOT, is a feature of the production of stop consonants. It is defined as the length of time that passes between when a stop consonant is released and when voicing, the vibration of the vocal folds, or, according to the authors, periodicity begins...
s, and regional accent.
Vocabulary expansion
In 1874 Carl Wernicke proposed that the ability to imitate speech plays a key role in language acquisition. This is now a widely researched issue in child developmentChild development
Child development stages describe theoretical milestones of child development. Many stage models of development have been proposed, used as working concepts and in some cases asserted as nativist theories....
. A study of 17,000 one and two word utterances made by six children between 18 months to 25 months found that, depending upon the particular infant
Infant
A newborn or baby is the very young offspring of a human or other mammal. A newborn is an infant who is within hours, days, or up to a few weeks from birth. In medical contexts, newborn or neonate refers to an infant in the first 28 days after birth...
, between 5% and 45% of their words might be mimicked. These figures are minima since they concern only immediately heard words. Many words that may seem spontaneous are in fact delayed imitations heard days or weeks previously. At 13 months children who imitate new words (but not ones they already know) show a greater increase in noun
Noun
In linguistics, a noun is a member of a large, open lexical category whose members can occur as the main word in the subject of a clause, the object of a verb, or the object of a preposition .Lexical categories are defined in terms of how their members combine with other kinds of...
vocabulary at four months and non noun vocabulary at eight months. A major predictor of vocabulary increase in both 20 months, 24 months, and older children between 4 and 8 years is their skill in repeating nonword phone sequences (a measure of mimicry and storage). This is also the case with children with Downs syndrome . The effect is larger than even age: in a study of 222 two year old children that had spoken vocabularies ranging between 3–601 words the ability to repeat nonwords accounted for 24% of the variance
Variance
In probability theory and statistics, the variance is a measure of how far a set of numbers is spread out. It is one of several descriptors of a probability distribution, describing how far the numbers lie from the mean . In particular, the variance is one of the moments of a distribution...
compared to 15% for age and 6% for gender
Gender
Gender is a range of characteristics used to distinguish between males and females, particularly in the cases of men and women and the masculine and feminine attributes assigned to them. Depending on the context, the discriminating characteristics vary from sex to social role to gender identity...
(girls better than boys).
Nonvocabularly expansion uses of imitation
Imitation provides the basis for making longer sentences than children could otherwise spontaneously make on their own. Children analyze the linguistic rulesSyntax
In linguistics, syntax is the study of the principles and rules for constructing phrases and sentences in natural languages....
, pronunciation patterns
Phonetics
Phonetics is a branch of linguistics that comprises the study of the sounds of human speech, or—in the case of sign languages—the equivalent aspects of sign. It is concerned with the physical properties of speech sounds or signs : their physiological production, acoustic properties, auditory...
, and conversational pragmatics
Pragmatics
Pragmatics is a subfield of linguistics which studies the ways in which context contributes to meaning. Pragmatics encompasses speech act theory, conversational implicature, talk in interaction and other approaches to language behavior in philosophy, sociology, and linguistics. It studies how the...
of speech by making monologue
Monologue
In theatre, a monologue is a speech presented by a single character, most often to express their thoughts aloud, though sometimes also to directly address another character or the audience. Monologues are common across the range of dramatic media...
s (often in crib talk
Crib talk
Crib talk or crib speech is pre-sleep monologue made by young children while in bed. This starts somewhere around one-and-a-half years and usually ends by about two-and-a-half years of age, though children can continue longer. It consists of conversational discourse with turn-taking often...
) in which they repeat and manipulate in word play
Word play
Word play or wordplay is a literary technique in which the words that are used become the main subject of the work, primarily for the purpose of intended effect or amusement...
phrases and sentences previously overheard. Many proto-conversations involve children (and parents) repeating what each other has said in order to sustain social and linguistic interaction. It has been suggested that the conversion of speech sound into motor responses helps aid the vocal “alignment of interactions” by “coordinating the rhythm and melody of their speech”. Repetition enables immigrant monolingual children to learn a second language by allowing them to take part in 'conversations'. Imitation related processes aids the storage of overheard words by putting them into speech based short- and long-term memory.
Language learning
The ability to repeat nonwords predicts the ability to learn second-language vocabulary. A study found that adult polyglotsMultilingualism
Multilingualism is the act of using, or promoting the use of, multiple languages, either by an individual speaker or by a community of speakers. Multilingual speakers outnumber monolingual speakers in the world's population. Multilingualism is becoming a social phenomenon governed by the needs of...
performed better in short-term memory tasks such as repeating nonword vocalizations compared to nonpolyglots though both are otherwise similar in general intelligence, visuo-spatial short-term memory and paired-associate learning ability. Language delay
Language delay
Language delay is a failure to develop language abilities on the usual developmental timetable. Language delay is distinct from speech delay, in which the speech mechanism itself is the focus of delay...
in contrast links to impairments in vocal imitation.
Speech repetition and phones
Electrical brain stimulationElectrical brain stimulation
Electrical brain stimulation , also referred to as focal brain stimulation , is a form of electrotherapy and technique used in research and clinical neurobiology to stimulate a neuron or neural network in the brain through the direct or indirect excitation of its cell membrane by using an electric...
research upon the human brain finds that 81% of areas that show disruption of phone identification are also those in which the imitating of oral movements is disrupted and vice versa; Brain injuries
Brain damage
"Brain damage" or "brain injury" is the destruction or degeneration of brain cells. Brain injuries occur due to a wide range of internal and external factors...
in the speech areas show a 0.9 correlation between those causing impairments to the copying of oral movements and those impairing phone production and perception.
Mechanism
Spoken words are sequences of motor movements organized around vocal tract gesture motor targets. Vocalization due to this is copied in terms of the motor goals that organize it rather than the exact movements with which it is produced. These vocal motor goals are auditory. According to James Abbs 'For speech motor actions, the individual articulatory movements would not appear to be controlled with regard to three- dimensional spatial targets, but rather with regard to their contribution to complex vocal tract goals such as resonance properties (e.g., shape, degree of constriction) and or aerodynamically significant variables'. Speech sounds also have duplicable higher-order characteristics such as rates and shape of modulations and rates and shape of frequency shifts. Such complex auditory goals (which often link—though not always—to internal vocal gestures) are detectable from the speech sound which they create.Dorsal speech processing stream function
Two cortical processing streams exist: a ventral one which maps sound onto meaning, and a dorsal one, that maps sound onto motor representations. The dorsal stream projects from the posterior Sylvian fissure at the temporoparietal junctionTemporoparietal junction
The temporoparietal junction is an area of the brain where the temporal and parietal lobes meet, at the posterior end of the Sylvian fissure...
, onto frontal motor areas, and is not normally involved in speech perception.
Carl Wernicke identified a pathway between the left posterior superior temporal sulcus
Superior temporal sulcus
The superior temporal sulcus is the sulcus separating the superior temporal gyrus from the middle temporal gyrus in the temporal lobe of the brain. The superior temporal sulcus is the first sulcus inferior to the lateral fissure....
(a cerebral cortex region sometimes called the Wernicke's area
Wernicke's area
Wernicke's area is one of the two parts of the cerebral cortex linked since the late nineteenth century to speech . It is involved in the understanding of written and spoken language...
) as a centre of the sound “images” of speech and its syllables that connected through the arcuate fasciculus
Arcuate fasciculus
The arcuate fasciculus is the neural pathway connecting the posterior part of the temporoparietal junction with the frontal cortex in the brain and is now considered as part of the superior longitudinal fasciculus..-Neuroanatomy:...
with part of the inferior frontal gyrus
Inferior frontal gyrus
The inferior frontal gyrus is a gyrus of the frontal lobe . It is labelled gyrus frontalis inferior, its Latin name...
(sometimes called the Broca's area
Broca's area
Broca's area is a region of the hominid brain with functions linked to speech production.The production of language has been linked to the Broca’s area since Pierre Paul Broca reported impairments in two patients. They had lost the ability to speak after injury to the posterior inferior frontal...
) responsible for their articulation. This pathway is now broadly identified as the dorsal speech pathway, one of the two pathways (together with the ventral pathway) that process speech. The posterior superior temporal gyrus
Superior temporal gyrus
The superior temporal gyrus is one of three gyri in the temporal lobe of the human brain, which is located laterally to the head, situated somewhat above the external ear.The superior temporal gyrus is bounded by:* the lateral sulcus above;...
is specialized for the transient representation of the phonetic sequences used for vocal repetition. Part of the auditory cortex also can represent aspects of speech such as its consonantal features.
Mirror neurons
Mirror neuronMirror neuron
A mirror neuron is a neuron that fires both when an animal acts and when the animal observes the same action performed by another. Thus, the neuron "mirrors" the behaviour of the other, as though the observer were itself acting. Such neurons have been directly observed in primate and other...
s have been identified that both process the perception and production of motor movements. This is done not in terms of their exact motor performance but an inference of the intended motor goals with which it is organized. Mirror neurons that both perceive and produce the motor movements of speech have been identified. According to the motor theory of speech imitation such speech mirror neurons in infants have selected for motor goals with vocal track gestures that are easy to imitate and this has shaped the nature of the phonetic units out of which spoken words are constructed. Speech is mirrored constantly into its articulations since speakers cannot know in advance that a word is unfamiliar and in need of repetition—which is only learnt after the opportunity to map it into articulations has gone. Thus, speakers if they are to incorporate unfamiliar words into their spoken vocabulary
must by default map all spoken input. The motor theory of speech imitation unlike that of motor theory of speech perception
Motor theory of speech perception
thumb|250px|right|When we hear [[speech|spoken words]] we sense that they are made of auditory [[sound]]s. The motor theory of speech perception argues that behind the sounds we hear are the intended movements of the [[vocal tract]] that [[pronunciation|pronounces]] them.The motor theory of speech...
does not link mirror neurons with speech perception
Speech perception
Speech perception is the process by which the sounds of language are heard, interpreted and understood. The study of speech perception is closely linked to the fields of phonetics and phonology in linguistics and cognitive psychology and perception in psychology...
.
Evolution and language
Human language is a vocabulary-based form of communication that unlike that of other animals employs tens of thousands of lexicals and names. This requires that young humans new to language have the ability to quickly learn both the pronunciations and use of many thousands of words. If children could not repeat speech without problems, human language could not exist. This makes the evolution of the capacity of speech repetition a critical innovation needed for the origin of speech The motor theory of speech imitation argues that this need for speech to be imitable not speech perception nor speech productionSpeech production
Speech production is the process by which spoken words are selected to be produced, have their phonetics formulated and then finally are articulated by the motor system in the vocal apparatus...
moreover underlies the evolved nature of the vowel
Vowel
In phonetics, a vowel is a sound in spoken language, such as English ah! or oh! , pronounced with an open vocal tract so that there is no build-up of air pressure at any point above the glottis. This contrasts with consonants, such as English sh! , where there is a constriction or closure at some...
and consonant units of phonetics.
Sign language
Words in sign languages unlike spoken ones are not made of sequential units but spatial configurations of subword unit arrangements. These words like spoken ones are learnt by imitation. Indeed, rare cases of compulsive sign-language echolalia exist in otherwise language-deficient deaf autistic individuals born into signing families. Both sign and vocal speech neurobiologically use the same cortical areas linked with imitation in the brain, with neural areas including the auditory cortex that are used for vocal speech being reused in sign language.Birds
BirdBird
Birds are feathered, winged, bipedal, endothermic , egg-laying, vertebrate animals. Around 10,000 living species and 188 families makes them the most speciose class of tetrapod vertebrates. They inhabit ecosystems across the globe, from the Arctic to the Antarctic. Extant birds range in size from...
s learn their songs from those made by other birds. In several examples, birds show highly developed repetition abilities: the Sri Lankan greater Greater Racket-tailed Drongo
Greater Racket-tailed Drongo
The Greater Racket-tailed Drongo, Dicrurus paradiseus, is a medium-sized Asian bird which is distinctive in having elongated outer tail feathers with webbing restricted to the tips. They are placed along with other drongos in the family Dicruridae...
(Dicrurus paradiseus) copies the calls of predators and the alarm signals of other birds Albert's Lyrebird
Albert's Lyrebird
The Albert's Lyrebird is a pheasant-sized songbird, approximately 90cm long, with brown upper body plumage and rich chestnut below. It is very similar with the Superb Lyrebird in its habits. This bird also mimics other species sounds....
(Menura alberti) can accurately imitate the Satin Bowerbird
Satin Bowerbird
The Satin Bowerbird, Ptilonorhynchus violaceus is a bowerbird endemic to eastern Australia.A rare natural intergeneric hybrid between the Satin Bowerbird and the Regent Bowerbird is known as Rawnsley's Bowerbird.-Distribution:...
(Ptilonorhynchus violaceus),
Research upon avian vocal motor neurons finds that they perceive their song as a series of articulatory gestures as in humans. Birds that can imitate humans, such as the Indian Hill myna
Hill Myna
The Common Hill Myna , sometimes spelled "mynah" and formerly simply known as "Hill Myna", is the myna bird most commonly seen in aviculture, where it is often simply referred to by the latter two names. It is a member of the starling family , resident in hill regions of South Asia and Southeast Asia...
(Gracula religiosa), imitate human speech by mimicking the various speech formants, created by changing the shape of the human vocal tract, with different vibration frequencies of its internal tympaniform membrane
Syrinx (biology)
Syrinx is the name for the vocal organ of birds. Located at the base of a bird's trachea, it produces sounds without the vocal cords of mammals. The sound is produced by vibrations of some or all of the membrana tympaniformis and the pessulus caused by air flowing through the syrinx...
. Indian hill mynahs also imitate such phonetic characteristics as voicing
Voice (phonetics)
Voice or voicing is a term used in phonetics and phonology to characterize speech sounds, with sounds described as either voiceless or voiced. The term, however, is used to refer to two separate concepts. Voicing can refer to the articulatory process in which the vocal cords vibrate...
, fundamental frequencies
Voice frequency
A voice frequency or voice band is one of the frequencies, within part of the audio range, that is used for the transmission of speech.In telephony, the usable voice frequency band ranges from approximately 300 Hz to 3400 Hz...
, formant transition
Formant
Formants are defined by Gunnar Fant as 'the spectral peaks of the sound spectrum |P|' of the voice. In speech science and phonetics, formant is also used to mean an acoustic resonance of the human vocal tract...
s, nasalization
Nasalization
In phonetics, nasalization is the production of a sound while the velum is lowered, so that some air escapes through the nose during the production of the sound by the mouth...
, and timing, through their vocal movements are made in a different way from those of the human vocal apparatus.
Nonhuman mammals
- Bottlenose dolphins can show spontaneous vocal mimicry of computer-generated whistles.
- Killer whales can mimic the barks of California sea lionCalifornia Sea LionThe California sea lion is a coastal sea lion of western North America. Their numbers are abundant , and the population continues to expand about 5% annually. They are quite intelligent and can adapt to man-made environments...
s. - Harbor sealHarbor SealThe harbor seal , also known as the common seal, is a true seal found along temperate and Arctic marine coastlines of the Northern Hemisphere...
s can mimic in a speech-like manner one or more English words and phrases - Elephants can imitate trunk sounds.
- Lesser spear-nosed batLesser Spear-nosed BatThe Lesser Spear-nosed Bat, Phyllostomus elongatus, is a bat species from South America. It is found in Bolivia, Brazil, Colombia, Ecuador, Guyana, Peru, Suriname and Venezuela....
can learn their call structure from artificial playback. - An orangutanOrangutanOrangutans are the only exclusively Asian genus of extant great ape. The largest living arboreal animals, they have proportionally longer arms than the other, more terrestrial, great apes. They are among the most intelligent primates and use a variety of sophisticated tools, also making sleeping...
has spontaneously copied the whistleWhistleA whistle or call is a simple aerophone, an instrument which produces sound from a stream of forced air. It may be mouth-operated, or powered by air pressure, steam, or other means...
s of humans.
Apes
Apes taught languageGreat Ape language
Research into non-human great ape language has involved teaching chimpanzees, bonobos, gorillas, and orangutans to communicate with human beings and with each other using sign language, physical tokens, and lexigrams; see Yerkish...
show an ability to imitate language signs with chimpanzee
Chimpanzee
Chimpanzee, sometimes colloquially chimp, is the common name for the two extant species of ape in the genus Pan. The Congo River forms the boundary between the native habitat of the two species:...
s such as Washoe
Washoe (chimpanzee)
Washoe was a chimpanzee who was the first non-human to learn to communicate using American Sign Language, as part of a research experiment on animal language acquisition....
who was able to learn with his arms a vocabularly of 250 American Sign Language
American Sign Language
American Sign Language, or ASL, for a time also called Ameslan, is the dominant sign language of Deaf Americans, including deaf communities in the United States, in the English-speaking parts of Canada, and in some regions of Mexico...
gestures. However, such human trained apes show no ability to imitate human speech vocalizations.
See also
- Alan BaddeleyAlan BaddeleyAlan David Baddeley FRS, CBE is a British psychologist. He is professor of psychology at the University of York. He is known for his work on working memory, in particular for his multiple components model.-Education:...
- Baddeley's model of working memoryBaddeley's Model of Working MemoryAlan Baddeley and Graham Hitch proposed a model of working memory in 1974, in an attempt to describe a more accurate model of short-term memory....
- Motor theory of speech perceptionMotor theory of speech perceptionthumb|250px|right|When we hear [[speech|spoken words]] we sense that they are made of auditory [[sound]]s. The motor theory of speech perception argues that behind the sounds we hear are the intended movements of the [[vocal tract]] that [[pronunciation|pronounces]] them.The motor theory of speech...
- Conduction aphasiaConduction aphasiaConduction aphasia, also called associative aphasia, is a relatively rare form of aphasia. An acquired language disorder, it is characterized by intact auditory comprehension, fluent speech production, but poor speech repetition. Patients will display frequent errors during spontaneous speech,...
- Echoic memoryEchoic memoryEchoic memoryis a type of sensory memory and auditory in nature; a component of sensory memory that is specific to retaining auditory information. Unlike visual memory, in which our eyes can scan the stimuli over and over, the auditory stimuli cannot be scanned over and over. Auditory stimuli is...
- EcholaliaEcholaliaEcholalia is the automatic repetition of vocalizations made by another person. It is closely related to echopraxia, the automatic repetition of movements made by another person....
- Language developmentLanguage developmentLanguage development is a process starting early in human life, when a person begins to acquire language by learning it as it is spoken and by mimicry. Children's language development moves from simple to complex. Infants start without language. Yet by four months of age, babies can read lips and...
- Language acquisitionLanguage acquisitionLanguage acquisition is the process by which humans acquire the capacity to perceive, produce and use words to understand and communicate. This capacity involves the picking up of diverse capacities including syntax, phonetics, and an extensive vocabulary. This language might be vocal as with...
- Language-based learning disability
- Mirror neurons
- Thematic coherenceThematic coherenceThematic coherence is a term that can be used both in linguistics as a literary technique or in developmental psychology; in the last case, it's said to be an organization of a set of meanings in and through an event...
- Mirroring (psychology)Mirroring (psychology)Mirroring is the behaviour in which one person copies another person usually while in social interaction with them. It may include miming gestures, movements, body language, muscle tensions, expressions, tones, eye movements, breathing, tempo, accent, attitude, choice of words/metaphors and other...
- Motor cognitionMotor cognitionThe concept of motor cognition grasps the notion that cognition is embodied in action, and that the motor system participates in what is usually considered as mental processing, including those involved in social interaction...
- Origin of languageOrigin of languageThe origin of language is the emergence of language in the human species. This is a highly controversial topic. Empirical evidence is so limited that many regard it as unsuitable for serious scholars. In 1866, the Linguistic Society of Paris went so far as to ban debates on the subject...
- Passive speakersPassive speakers (language)A passive speaker is someone who has had enough exposure to a language in childhood to have a native-like comprehension of it, but has little or no active command of it....
- Phonological developmentPhonological developmentSound is at the beginning of language learning. Children have to learn to distinguish different sounds and to segment the speech stream they are exposed to into units – eventually meaningful units – in order to acquire words and sentences...
- PronunciationPronunciationPronunciation refers to the way a word or a language is spoken, or the manner in which someone utters a word. If one is said to have "correct pronunciation", then it refers to both within a particular dialect....
- Proprioceptive Language Learning MethodProprioceptive Language Learning MethodThe proprioceptive language learning method is a language learning technique which emphasizes simultaneous development of cognitive, motor, neurological, and auditory functions as all being part of a comprehensive language learning process...
- Second language acquisitionSecond language acquisitionSecond-language acquisition or second-language learning is the process by which people learn a second language. Second-language acquisition is also the name of the scientific discipline devoted to studying that process...
- Short-term memoryShort-term memoryShort-term memory is the capacity for holding a small amount of information in mind in an active, readily available state for a short period of time. The duration of short-term memory is believed to be in the order of seconds. A commonly cited capacity is 7 ± 2 elements...
- Speech perceptionSpeech perceptionSpeech perception is the process by which the sounds of language are heard, interpreted and understood. The study of speech perception is closely linked to the fields of phonetics and phonology in linguistics and cognitive psychology and perception in psychology...
- Transcortical motor aphasiaTranscortical motor aphasiaTranscortical Motor Aphasia , also known as adynamic aphasia and extrasylvian motor aphasia, results from an injury to the anterior superior frontal lobe. The injury is typically caused by a cerebrovascular accident , commonly referred to as a stroke. The area of insult is sometimes referred to as...
- Transcortical sensory aphasiaTranscortical sensory aphasiaTranscortical sensory aphasia is caused by lesions in the inferior left temporal lobe of the brain located near Wernicke's area, and is usually due to minor hemorrhage or contusion in the temporal lobe, or infarcts of the left posterior cerebral artery...
- Vocabulary growth
- Vocal learningVocal learningVocal learning is the ability of animals to modify vocal signals in form as a result of experience with those of other individuals. This can lead to signals that are either similar or dissimilar to the model...