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PSYCHOLOGY OF LANGUAGE Heather Ferguson. OVERVIEW 1. Definition of language 2. Stages of language perception 3. Stages of language production 4. Theories.

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Presentation on theme: "PSYCHOLOGY OF LANGUAGE Heather Ferguson. OVERVIEW 1. Definition of language 2. Stages of language perception 3. Stages of language production 4. Theories."— Presentation transcript:

1 PSYCHOLOGY OF LANGUAGE Heather Ferguson

2 OVERVIEW 1. Definition of language 2. Stages of language perception 3. Stages of language production 4. Theories of language acquisition Critical period hypothesis Critical period hypothesis Case study Case study 5. Bilingualism

3 WHAT IS LANGUAGE? The systematic, conventional use of sounds, signs, or written symbols in a human society for communication and self-expression. David Crystal

4 STAGES OF LANGUAGE PERCEPTION At birth Already prefer the sounds of their mothers voice Can discriminate between mothers native language an other languages

5 Discriminating sounds Adult speakers have difficulty discriminating between language sounds that are not phonemic contrasts in their native language Adult speakers have difficulty discriminating between language sounds that are not phonemic contrasts in their native language Young infants do not demonstrate this difficulty initially Young infants do not demonstrate this difficulty initially They can discriminate any contrasting phonetic sounds in the worlds languages They can discriminate any contrasting phonetic sounds in the worlds languages

6 How can we possibly know that? Are /s/ and /ç/ different sounds for you, baby?

7 Testing Infants Some helpful things infants do for experimenters: Some helpful things infants do for experimenters: They look longer at new stimuli compared to familiar stimuli They look longer at new stimuli compared to familiar stimuli They suck faster when exposed to new stimuli They suck faster when exposed to new stimuli

8 Testing Infants Habituation-dishabituation method Habituation-dishabituation method Habituate infant on one stimulus Habituate infant on one stimulus Show new, different stimulus Show new, different stimulus Does the infant react to the new stimulus as new? Does the infant react to the new stimulus as new? Habituation-dishabituation measures Habituation-dishabituation measures Time looks to stimulus Time looks to stimulus High-amplitude sucking paradigm High-amplitude sucking paradigm Does the infant start sucking faster on a pacifier (thats hooked up to a monitoring device)? Does the infant start sucking faster on a pacifier (thats hooked up to a monitoring device)?

9 Testing Infants ba ba ba

10 Testing Infants ba ba pa ba ba ba

11 Limited-time Offer However, infants can only discriminate all phonemes for a limited period of time However, infants can only discriminate all phonemes for a limited period of time At 4 to 6 months phonetic sensitivity diminishes. At 4 to 6 months phonetic sensitivity diminishes. By 12 months, infants are very poor at distinguishing foreign contrasts By 12 months, infants are very poor at distinguishing foreign contrasts The (speech) perceptual system is being reorganized around these time periods (4- 6 months & months) The (speech) perceptual system is being reorganized around these time periods (4- 6 months & months)

12 Theory Exposure and habituation to the sounds of the target language impedes an infants ability to perceive phonetic contrasts that the native language does not make Exposure and habituation to the sounds of the target language impedes an infants ability to perceive phonetic contrasts that the native language does not make There are innate language abilities that are lost due to experience with a first language There are innate language abilities that are lost due to experience with a first language One is born with all language sounds available, but sound distinctions are lost as sound system develops One is born with all language sounds available, but sound distinctions are lost as sound system develops

13 Phonemic Organization Account Loss of perceptual ability is related to development of phonemic categories for the first language- phonemic organization Loss of perceptual ability is related to development of phonemic categories for the first language- phonemic organization

14 Infant-directed Speech 7-week-old infants prefer infant- directed speech (motherese) to adult-directed speech Regardless of gender of speaker Older infants show this preference as well, but younger infants are more responsive, both in terms of attention and affect

15 STAGES OF LANGUAGE PRODUCTION The larynx The larynx At birth- the larynx is relatively high, and entire vocal tract is quite different from adults At birth- the larynx is relatively high, and entire vocal tract is quite different from adults At 3 months- larynx begins to descend (wont reach adult location until ~3 years old) At 3 months- larynx begins to descend (wont reach adult location until ~3 years old) At 4 months- the vocal tract begins to resemble an adult vocal tract At 4 months- the vocal tract begins to resemble an adult vocal tract

16 Infant Speech Production Because of their maturing vocal tract, some sounds are genuinely difficult for young children to produce Because of their maturing vocal tract, some sounds are genuinely difficult for young children to produce

17 Stage I (0-8 weeks): Basic biological noises Reflexive Reflexive Hunger, pain and discomfort resulting in crying Hunger, pain and discomfort resulting in crying Vegetative Vegetative Sucking, swallowing, coughing, burping Sucking, swallowing, coughing, burping Airstream mechanism and vocal folds used to produce pitch patterns in a rhythmical fashion Airstream mechanism and vocal folds used to produce pitch patterns in a rhythmical fashion

18 Stage II (2-5 months): Cooing and laughing Cooing sounds develop alongside crying Cooing sounds develop alongside crying Quieter, lower-pitched and more musical than crying Quieter, lower-pitched and more musical than crying Short-vowel-like sounds preceded by a consonant-like sound produced at the back of the mouth Short-vowel-like sounds preceded by a consonant-like sound produced at the back of the mouth No rhythm or intonational contour No rhythm or intonational contour Laughing sounds emerge at around 4 months Laughing sounds emerge at around 4 months

19 Stage III (5-7 ½ months): Vocal Play High-pitched segments over one second long, frequently repeated (longer in duration than cooing) High-pitched segments over one second long, frequently repeated (longer in duration than cooing) Wider intonation ranges (low to high) Wider intonation ranges (low to high) Large inventory of consonant and vowel sounds, with periodic focus on particular places of articulation Large inventory of consonant and vowel sounds, with periodic focus on particular places of articulation

20 Stage IV (~6-12 months): Babbling Features of babbling: Features of babbling: Sounds are a subset of possible sounds found in spoken language Sounds are a subset of possible sounds found in spoken language Syllabic organisation Syllabic organisation Reduplication Reduplication Same two sounds repeated (babababa papapapap) Same two sounds repeated (babababa papapapap) Variegated babbling (~12 months) Variegated babbling (~12 months) Sounds change between syllables (bamipabo) Sounds change between syllables (bamipabo)

21 Stage IV (~6-12 months): Babbling Features of babbling: Features of babbling: Lack of meaning/ reference Lack of meaning/ reference Rhythm and intonation reminiscent of speech Rhythm and intonation reminiscent of speech Continuity of phonetic form and syllable type between a childs babbling and first words Continuity of phonetic form and syllable type between a childs babbling and first words Infants will often seem to practise when alone Infants will often seem to practise when alone Suggests that babbling is related more to practising speech sounds than communication Suggests that babbling is related more to practising speech sounds than communication

22 Babbling & Sign Language Deaf infants also babble Deaf infants also babble Often delayed (11-24 months) compared to hearing infants Often delayed (11-24 months) compared to hearing infants Often different in character (e.g. fewer different kinds of consonants) Often different in character (e.g. fewer different kinds of consonants) This indicates that exposure to a spoken language influences babbling This indicates that exposure to a spoken language influences babbling Infants (hearing and deaf) who are exposed to sign language will babble manually Infants (hearing and deaf) who are exposed to sign language will babble manually

23 Stage V (9-18months): Melodic Utterance Variations in melody, rhythm and intonation become a major feature toward the end of the first year Variations in melody, rhythm and intonation become a major feature toward the end of the first year Begins to sound language-like Begins to sound language-like

24 First Words Around 12 months Around 12 months Focus on words related to the here and now, concrete things: Focus on words related to the here and now, concrete things: Peoples names, toys, clothes, food they eat Peoples names, toys, clothes, food they eat Words for things that they can influence (one- word stage) Words for things that they can influence (one- word stage) ball likely to be learned earlier than chair or tree ball likely to be learned earlier than chair or tree

25 First Words Two kinds of errors children can make: Two kinds of errors children can make: 1. Overextension- refer to all four legged animals as dogs 2. Underextension- refer to only the family dog as dog

26 The Mapping Problem Child says Whats that? and points to: Child says Whats that? and points to: So…how could this possibly go wrong? So…how could this possibly go wrong?

27 The Mapping Problem Potential problems: Potential problems: More than one referent could apply to the word, teacup More than one referent could apply to the word, teacup

28 The Mapping Problem Potential problems: Potential problems: More than one word may apply to a referent: More than one word may apply to a referent: Tea? Tea? Teacup? Teacup? Saucer? Saucer? A drink? A drink? Cup? Cup?

29 The Mapping Problem Apparent solutions: Apparent solutions: Whole object bias- children prefer to attach new labels to the whole object Whole object bias- children prefer to attach new labels to the whole object Mutual exclusivity bias- children prefer to have only one name for an object Mutual exclusivity bias- children prefer to have only one name for an object

30 Early Multiword Utterances By about 15months babies have a vocabulary of about words By about 15months babies have a vocabulary of about words Two years Two years Vocabulary rapidly increases to 100s of words Vocabulary rapidly increases to 100s of words Child constructs primitive sentences- two-word stage (no eat, throw ball) Child constructs primitive sentences- two-word stage (no eat, throw ball)

31 Early Multiword Utterances Thirty months Utterances progress beyond 2- word stage and show basic propositional structure (telegraphic stage) Functional words appear (the, in, of) Children overgeneralise rules (goed) Five years old Basic structure of language is in place Vocabulary of words

32 THEORIES OF LANGUAGE ACQUISITION 1. Nativist Theories Language is entirely innate Language is entirely innate 2. Learning Theories Language is entirely learned Language is entirely learned 3. Cognitive Theories Language development is related to other cognitive developments Language development is related to other cognitive developments 4. Social Interactionist Theory Language is acquired through communicative interaction Language is acquired through communicative interaction

33 NATIVISM Emphasizes a childs inborn capacities for language Emphasizes a childs inborn capacities for language Language is acquired through a genetic program Language is acquired through a genetic program Language acquisition is distinct from other cognitive processes Language acquisition is distinct from other cognitive processes

34 NATIVISM Noam Chomsky- the language acquisition device (LAD) Noam Chomsky- the language acquisition device (LAD) Children are born with a basic understanding of language and a mental capacity to learn it quickly Children are born with a basic understanding of language and a mental capacity to learn it quickly Brain is over- connected at birth. Connections that are not used die or become dormant, and new connections based on experience form Brain is over- connected at birth. Connections that are not used die or become dormant, and new connections based on experience form There is a specific time period of function There is a specific time period of function

35 NATIVISM Universal grammar: Universal grammar: Children are pre-programmed with a kind of default language which can be altered with exposure to a specific language Children are pre-programmed with a kind of default language which can be altered with exposure to a specific language Key assumption: Key assumption: Infants develops language even when other cognitive skills are low Infants develops language even when other cognitive skills are low

36 Evidence in Favour of a Pre-determined Biological Language System: 1. Other primates dont learn language simply by being treated like human infants Gua (chimp, 1993) Gua (chimp, 1993) Raised alongside a 9½month-old boy for 9 months Raised alongside a 9½month-old boy for 9 months Never spoke but learned to comprehend spoken requests Never spoke but learned to comprehend spoken requests Viki (chimp, 1951) Viki (chimp, 1951) Raised alone from 3 days- 7 years old Raised alone from 3 days- 7 years old Capable of picture recognition, sorting of pictures and objects into conceptual categories Capable of picture recognition, sorting of pictures and objects into conceptual categories Understood large number of words and phrases Understood large number of words and phrases But, comprehension contextually determined But, comprehension contextually determined

37 Evidence in Favour of a Pre-determined Biological Language System: 2. Children with other cognitive deficits still learn language Language skills can persist even in cases of profound mental retardation Language skills can persist even in cases of profound mental retardation

38 Evidence in Favour of a Pre-determined Biological Language System: 3. Poverty of the stimulus Language input to children is ill-formed and incomplete (motherese) Language input to children is ill-formed and incomplete (motherese) Children dont receive explicit rules about what not to do Children dont receive explicit rules about what not to do They dont get it even if you do tell them They dont get it even if you do tell them

39 Evidence in Favour of a Pre-determined Biological Language System: 4. Creoles Pidgins develop in language contact situations (mostly colonial) Pidgins develop in language contact situations (mostly colonial) (Pidgin = a language that has been constructed from two or more shared languages for communication between communities. A pidgin is not a mother tongue) (Pidgin = a language that has been constructed from two or more shared languages for communication between communities. A pidgin is not a mother tongue) Creoles develop from children exposed primarily to pidgins Creoles develop from children exposed primarily to pidgins (Creole = a language that has developed from a mixture of languages) (Creole = a language that has developed from a mixture of languages) Children are, in essence, filling the gaps of pidgins Children are, in essence, filling the gaps of pidgins

40 Evidence in Favour of a Pre-determined Biological Language System: 5. Evidence for critical period of language acquisition

41 THE CRITICAL PERIOD HYPOTHESIS Eric Lenneberg, 1967

42 THE CRITICAL PERIOD HYPOTHESIS Lenneberg theorized that… Lenneberg theorized that… The acquisition of language is an innate (you are born with it) process The acquisition of language is an innate (you are born with it) process Biological factors limit the critical period for acquisition of a language to a window of opportunity from roughly two years of age to puberty Biological factors limit the critical period for acquisition of a language to a window of opportunity from roughly two years of age to puberty If a child does not learn a language before the onset of puberty, the child will never master language at all If a child does not learn a language before the onset of puberty, the child will never master language at all

43 Bird Song and the Critical Period Hypothesis Some birds (like Sparrows) have courtship songs Some birds (like Sparrows) have courtship songs Songs have dialectal variation Songs have dialectal variation Individual song is a version of other songs it hears during the critical period of first 100 days of life Individual song is a version of other songs it hears during the critical period of first 100 days of life Bird learns song by trial and error (babbling) Bird learns song by trial and error (babbling) When deprived of song input early in life, they fail to produce a normal song When deprived of song input early in life, they fail to produce a normal song

44 THE CRITICAL PERIOD HYPOTHESIS The critical period and the human brain… The critical period and the human brain… Lenneberg believed that after lateralization (a process by which the two sides of the brain develop specialized functions), the brain loses plasticity Lenneberg believed that after lateralization (a process by which the two sides of the brain develop specialized functions), the brain loses plasticity Lenneberg claimed that lateralization of the language function is normally completed at puberty, making post-adolescent language acquisition difficult Lenneberg claimed that lateralization of the language function is normally completed at puberty, making post-adolescent language acquisition difficult

45 CASE STUDY The story of Genie

46 The Story of Genie Read about Genie and decide for yourself… Read about Genie and decide for yourself… How does Genies language development relate to Lennebergs theory? How does Genies language development relate to Lennebergs theory? What is the strongest evidence in support of the Critical Period Hypothesis What is the strongest evidence in support of the Critical Period Hypothesis Was Genies early language deprivation the ONLY thing that contributed to her abnormal language development? Was Genies early language deprivation the ONLY thing that contributed to her abnormal language development?

47 The Story of Genie Main points… Main points… From 20 months- 13 years old Genie was not allowed to make noise and was not spoken to (father barked or growled at her) From 20 months- 13 years old Genie was not allowed to make noise and was not spoken to (father barked or growled at her) When found could not speak or understand words (except name and sorry) When found could not speak or understand words (except name and sorry) Over time, vocab increased and she learned to speak in 2/ 3- word sentences Over time, vocab increased and she learned to speak in 2/ 3- word sentences BUT, speech has remained garbled and she has never mastered grammar needed for language BUT, speech has remained garbled and she has never mastered grammar needed for language

48 Genie and the Critical Period Hypothesis At first, a number of researchers thought that Genie would prove Lennebergs theory wrong as… At first, a number of researchers thought that Genie would prove Lennebergs theory wrong as… 1 year after her escape she was producing 2/ 3- word sentences 1 year after her escape she was producing 2/ 3- word sentences She could distinguish between singular/ plural nouns and positive and negative sentences She could distinguish between singular/ plural nouns and positive and negative sentences Genies language resembled that of a normal month old child Genies language resembled that of a normal month old child

49 Genie and the Critical Period Hypothesis BUT, BUT, As time went on, Genies vocab did not explode as is the case with normally developing children As time went on, Genies vocab did not explode as is the case with normally developing children Four years later… Four years later… She still had not mastered grammar She still had not mastered grammar She could not ask questions properly (where is may I have a penny) She could not ask questions properly (where is may I have a penny) She confused pronouns, using you and me interchangeably She confused pronouns, using you and me interchangeably

50 Genie and the Critical Period Hypothesis Has Genie supported Lennebergs theory?NO! Has Genie supported Lennebergs theory?NO! Why? Why? Genies personal history was so disastrous that it is not clear why she did not make progress with her language Genies personal history was so disastrous that it is not clear why she did not make progress with her language It is possible that Genie did not master language because she had passed the critical period It is possible that Genie did not master language because she had passed the critical period BUT, other explanations are available BUT, other explanations are available

51 Genie and the Critical Period Hypothesis Genies brain may have been abnormal Genies brain may have been abnormal Brain scans showed that Genies brain was unusual Brain scans showed that Genies brain was unusual As we know, for most people, the areas of the brain responsible for language functions are located in the left hemisphere As we know, for most people, the areas of the brain responsible for language functions are located in the left hemisphere BUT, Genies brain was dominated by the right hemisphere BUT, Genies brain was dominated by the right hemisphere

52 Genie and the Critical Period Hypothesis Conclusions… Conclusions… Genies lack of progress does suggest that, over a certain age, any child who has not learnt a language will have difficulty acquiring one Genies lack of progress does suggest that, over a certain age, any child who has not learnt a language will have difficulty acquiring one BUT, other explanations can not be ruled out BUT, other explanations can not be ruled out Therefore, Lennebergs hypothesis is not proven, but it is strongly supported Therefore, Lennebergs hypothesis is not proven, but it is strongly supported

53 LEARNING THEORIES Associated with Skinner, Pavlov, etc Associated with Skinner, Pavlov, etc Language is learned through basic processes like associations, reinforcement and imitation Language is learned through basic processes like associations, reinforcement and imitation Language acquisition occurs through three processes: Language acquisition occurs through three processes:

54 LEARNING THEORIES 1. Classical Conditioning USUR US+CSCR bottle bottle CSCR bottle bottle

55 LEARNING THEORIES 2. Operant Conditioning Reinforcement/ rewards Reinforcement/ rewards Children are rewarded for early attempts at language Children are rewarded for early attempts at language Selective reinforcement shapes childrens language as the requirement for a reward becomes more specific Selective reinforcement shapes childrens language as the requirement for a reward becomes more specific

56 LEARNING THEORIES 3. Social learning Observation and imitation of others, especially those who are powerful, nurturing and similar to the child Observation and imitation of others, especially those who are powerful, nurturing and similar to the child

57 Limitations of Learning Theories BUT, these processes can not fully account for language development in children because… BUT, these processes can not fully account for language development in children because… Not enough to explain the complexities of language itself Not enough to explain the complexities of language itself Most parents do not consistently reinforce proper speech Most parents do not consistently reinforce proper speech Children say things they would not have heard an adult say Children say things they would not have heard an adult say Aspects of language development are universal and do not vary with different experiences Aspects of language development are universal and do not vary with different experiences

58 COGNITIVE THEORIES Language is unique to humans Language is unique to humans But, not a modular, pre-programmed ability But, not a modular, pre-programmed ability General disposition for learning that allows language General disposition for learning that allows language Pattern recognition Pattern recognition Imitation Imitation Language development is related to other forms of development Language development is related to other forms of development For these kinds of theories to be true infants must have general skills that clearly contribute to language For these kinds of theories to be true infants must have general skills that clearly contribute to language

59 Cognition and Language Cognitive skills that are not language specific but none-the-less contribute to language Cognitive skills that are not language specific but none-the-less contribute to language Newborns prefer face-like to non-face-like stimuli Newborns prefer face-like to non-face-like stimuli Quickly learn to recognize their mothers face Quickly learn to recognize their mothers face Young infants focus on the eye region more than other facial regions Young infants focus on the eye region more than other facial regions More inclined to look at a pleasantly moving face than a still one More inclined to look at a pleasantly moving face than a still one

60 Cognition and Language Infants know much more than they can demonstrate physically Infants know much more than they can demonstrate physically So, infants come to the language environment with a much more sophisticated view of the world than has been previously thought So, infants come to the language environment with a much more sophisticated view of the world than has been previously thought LAD not necessarily needed! LAD not necessarily needed!

61 INTERACTIONIST VIEW Both inborn capacities and learning are important Both inborn capacities and learning are important Emphasizes the use of language and the fit between the child and the language environment Emphasizes the use of language and the fit between the child and the language environment Jerome Bruner- the language acquisition support system (LASS) Jerome Bruner- the language acquisition support system (LASS) Social context of language development is important Social context of language development is important Language- skilled adults structure and support the childs language learning environment Language- skilled adults structure and support the childs language learning environment

62 INTERACTIONIST VIEW Parent- child language interaction characterised by: Parent- child language interaction characterised by: Infant- directed speech (motherese) Infant- directed speech (motherese) High- pitched, simple, redundant speech adults use with babies High- pitched, simple, redundant speech adults use with babies Recasting Recasting Rephrasing what child says, often as a question Rephrasing what child says, often as a question Echoing Echoing Repeating what a child says Repeating what a child says Expanding Expanding Restating in a more advanced way what a child says Restating in a more advanced way what a child says Labelling Labelling Naming objects Naming objects

63 SUMMARY OF THEORIES OF LANGUAGE ACQUSITION Language is clearly genetically specified Language is clearly genetically specified It appears that only humans develop a full version of it It appears that only humans develop a full version of it But not yet established to what extent language is directly specified and to what extent its development is tied up with other aspects of cognitive and social development But not yet established to what extent language is directly specified and to what extent its development is tied up with other aspects of cognitive and social development

64 BILINGUALISM

65 Bilingualism and the Critical Period Hypothesis What is a bilingual? What is a bilingual? A person who uses or is able to use two languages, especially with equal fluency A person who uses or is able to use two languages, especially with equal fluency Is there a cognitive advantage to bilingualism? Is there a cognitive advantage to bilingualism? Early studies showing a disadvantage Early studies showing a disadvantage – Studies of immigrants – Confounded by social class Later studies showing an advantage Later studies showing an advantage – Avoided social class confounds – Picked up new confounds eg. who is bilingual?

66 Bilingualism and the Critical Period Hypothesis Evidence for… Evidence for… It is significantly harder for older adults to master a second language It is significantly harder for older adults to master a second language Evidence against… Evidence against… Some late L2 learners can become perfectly fluent speakers (Long, 1990; Birdsong, 1992) Some late L2 learners can become perfectly fluent speakers (Long, 1990; Birdsong, 1992)

67 Brain and Bilingualism: Issues Are the separate languages of bilinguals stored in separate parts of the brain? Are the separate languages of bilinguals stored in separate parts of the brain? Does neural representation vary with age of acquisition? Does neural representation vary with age of acquisition? Is there a language switch somewhere in the brain? Is there a language switch somewhere in the brain?

68 Brain and Bilingualism Mixed evidence for differing brain regions in early and late bilinguals… Mixed evidence for differing brain regions in early and late bilinguals… Some studies have found similar patterns in early and late bilinguals (Chee et al., 1999b) Some studies have found similar patterns in early and late bilinguals (Chee et al., 1999b)

69 Brain and Bilingualism But, some fMRI studies have found different patterns of activation in sentence production in early and late bilinguals (Kim et al., 1997) But, some fMRI studies have found different patterns of activation in sentence production in early and late bilinguals (Kim et al., 1997)

70 Bilingualism Conclusions The two or more languages of bilinguals are distributed across the same brain regions that are used by monolinguals (Brocas and Wernickes) The two or more languages of bilinguals are distributed across the same brain regions that are used by monolinguals (Brocas and Wernickes) For both monolinguals and bilinguals, the regions involved in language use vary by task, expertise and strategy For both monolinguals and bilinguals, the regions involved in language use vary by task, expertise and strategy The same areas may have to work harder and additional areas may be recruited for processing in the weaker language The same areas may have to work harder and additional areas may be recruited for processing in the weaker language Second language learning appears to be easier in the critical period than later in life, BUT it is possible to become fluent in a second language Second language learning appears to be easier in the critical period than later in life, BUT it is possible to become fluent in a second language Second language is not necessarily the weaker language! Second language is not necessarily the weaker language!

71 LANGUAGE REFERENCES Gleitman, H. 1999: Language in Psychology. Chapter 9, pp Gleitman, H. 1999: Language in Psychology. Chapter 9, pp Bee, H. The developing Child Bee, H. The developing Child


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