can produce all utterances from a basic set of approximately 40 sounds can produce and comprehend sentences you ve never said/heard before

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1 Language Page 1 of 12 What is language? Defining features productivity displacement arbitrariness language operates by (implicit) rules Language Properties Productivity can produce all utterances from a basic set of approximately 40 sounds Novelty can produce and comprehend sentences you ve never said/heard before My hovercraft is full of eels Infinite There are an infinite number of sentences 1. My favorite number is not My favorite number is not My favorite number is not My favorite number is not 4 Ambiguity

2 Page 2 of 12 Phoneme No invariant in the acoustic signal coarticulation Morpheme Bill files the saw Bill saw the files Sentence Visiting relatives can be a nuisance What is language? More defining features transmitted by cultures (not by birth) spontaneously acquired language is constantly changing language is hierarchically structured Do animals have language? Does your dog (or cat) communicate? Is that language, i.e., does it have any of the defining features of language? Vervet Monkeys Three distinct sounds meaning snake, tiger, hawk. Clearly discriminate between them. Is it language?

3 Do animals have language? Page 3 of 12 Savage-Rumbaugh s bonobo chimpanzee Kanzi. vocabulary of 200 words and was able to construct sentences by combining words with gestures or with other words. Kanzi's most notable accomplishment: he was told, "Give the dog a shot," and he to injected his stuffed dog with a syringe. Critics -- not proof of language ability in primates because the crucial element in language ability is production, not comprehension. Washoe Date Of Birth: Unknown; estimated to be in December, Central Washington University's Chimpanzee and Human Communication Institute (CHCI) Washoe was raised as if she were a deaf child by Beatrix and Allen Gardner at the University of Nevada in Reno (1966 to 1970). Immersed in American Sign Language with a socially enriched environment where she soon learned to use ASL in daily interactions with her human companions. Approximately 240 signs Is it language? Depends on definition of language Not very good evidence for novelty Very good evidence for communication

4 Page 4 of 12 Limited because of memory? because of inability? Can animals use language? Depends on your definition of language. Sapir-Whorf Hypothesis Edward Sapir and Benjamin Whorf Strong version The language you speak determines/limits what you can think about Weak version Some concepts are easier to think about in some languages than in others Strong Version Problems Assumes only possible mode of thought is verbal (propositional) Eskimos don t have more words for snow Does language determine thought? Most people think not. Most agree that language influences thought but does not determine it (weak version of the Sapir/Whorf hypothesis). Laterality

5 Page 5 of 12 Approximately 80% right handed Of 20% that are left handed, more have brain organization like right handers What do you mean by left handed? brushing teeth? eye dominance? hemispheric specialization? Laterality of language Aphasias--language disorders Broca s aphasia--near motor areas, affects primarily language production. Wernicke s aphasia--primary auditory cortex, affects primarily language understanding. Mainly occur when there is damage to the left hemisphere. Split Brain Patients Corpus Callosum severed Left and Right hemispheres cannot communicate Usually to prevent seizures from spreading Hemispheres Corpus Callosum Enormous bundle of axons which interconnects the left and right cerebral hemispheres.

6 Right Handed Male Page 6 of 12 Language centers in left hemisphere Left hemisphere controls right hand Right hemisphere controls left hand Left visual field goes to right hemisphere Right visual field goes to left hemisphere Hemispherectomy Remove hemisphere Can learn language Adaptive development Sign language users Language mainly centered in left hemisphere. Spatial abilities more in right hemisphere. What about sign language? If it is like spoken language, left hemisphere damage should affect it. If it is mainly spatial, right hemisphere damage should affect it. Speech Production Very complex motor coordination. Musical instrument metaphor

7 Vocal cords are like strings. Page 7 of 12 Diaphram, lungs, trachea, mouth, etc., are like wind instrument. Phoneme Basic sound unit Approximately 40 phonemes in American English 15 Vowels (and diphthongs) 25 Consonants Sounds, not letters Consonants Voiced or voiceless ssssssss vs zzzzzzzz Place of articulation (obstruction) lips (labial), teeth (dental), alveolar ridge (alveolar) hard palate (palatal), soft palate (velar), throat (glottal) Manner of articulation plosive, fricative, nasal, lateral (l), affricate (plosive followed by fricative, ch) Vowels height and place of tongue Levels of Language Four components: sound system (phonemes)

8 vocabulary (semantics) Page 8 of 12 basic rules (syntax) social rules (pragmatics) All four components together make up a grammar Speech Mechanistic energy that requires a medium (e.g., air, water) Begins with vibration, pushes air molecules, forms a wave Waves vary in amplitude, wavelength, and frequency Hearing Normal hearing 20-20,000 Hz Best hearing is around 1000 Hz Most of the information in speech is between Hz Speech Perception stream segregation same sounds perceived as different ordering of sounds variability a) ambient conditions b) within-speaker variability c) between-speaker variability d) context changes

9 e) speaking rate Page 9 of 12 f) word environment Spectrogram A visual representation of sound The horizontal dimension corresponds to time (reading from left to right), and the vertical dimension corresponds to frequency The relative intensity of the sound at any particular time and frequency is indicated by the darkness of the spectrogram at that point. Phonemes There is no simple one-to-one relation between the sound (formant transitions) and the perceived consonant. Innate Motor Theory of Speech Perception There is a close link between perception and production Determine the articulatory gesture Use the production (motor) system to determine what phoneme the articulatory gesture produces Only humans have speech/language Motor Theory Categorical Perception McGurk Effect

10 Page 10 of 12 Children Categorical Perception Continuum Delay onset of voicing by 5 ms Stimulus 2 voicing starts 5 ms later than for Stimulus 1 Stimulus 1 sounds like /ba/ Stimulus 9 sounds like /pa/ What do stimuli 4, 5, and 6 sound like? Weber s Law Categorical Perception violates Weber s Law A smaller proportion change is easier to detect than a larger proportion change

11 McGurk Effect Page 11 of 12 Most adults report hearing /DA/ A so-called fused response in which the /D/ is a result of an audio-visual illusion hearing the sound /BA/ seeing the lip movements /GA/ Auditory Theory Speech is specialized, but not special Derives from general properties of the auditory system Language Comprehension Bottom-up processes sensation, perception Top-down proceses common knowledge (common ground), knowledge, expectations, schemas Pragmatics Practical knowledge used to comprehend a speaker and provide an appropriate response Gricean Maxims Be informative Tell the truth Be relevant

12 Page 12 of 12 Be clear Top-Down Processing Any sentence has an infinite number of meanings The sky is blue The sky is blue It is your turn to take the dog for a walk The newspaper will be readable Boy, did I oversleep Syntax Set of rules that determine how words combine to form legal sentences Rules are unknown Noam Chomsky Surface structure: actual words Deep structure: meaning Transformation: rules to transform between Ambiguous Visiting relatives can be a nuisance Having relatives come to visit you can be a nuisance Having to go a visit relatives can be a nuisance Same surface structure, different deep structure