Fundamentals of Human Language Processing: Psycholinguistics
What is Psycholinguistics?
Psycholinguistics studies how language is acquired, represented, processed, and used in the human mind/brain. It focuses on language production, comprehension, and acquisition.
Creativity of Human Language
- Human language is infinitely creative.
- Speakers can produce and understand novel sentences they have never heard before.
- This is possible because language uses rules plus a finite vocabulary results in infinite sentences.
Language vs. Speech vs. Thought vs. Communication
Language ≠ Speech
- Speech is only a mode of transmission.
- Language is an abstract mental system.
Language ≠ Thought
- Thought can exist without language (e.g., infants, animals).
- Language and intelligence are independent systems.
Language ≠ Communication
- Not all communication is linguistic (gestures, music, math).
The Linguistic System
Language is a system that pairs sound (signal) with meaning. It includes:
- Grammar (rules)
- Lexicon (vocabulary)
Knowledge of language is tacit (implicit), not conscious.
Descriptive vs. Prescriptive Grammar
Descriptive grammar: how people actually speak.
Prescriptive grammar: rules about how people should speak.
Psycholinguistics focuses on descriptive grammar, not correctness.
Universality of Language
All human languages share:
- Grammar + lexicon
- Infinite productivity
- Language is biologically based and unique to humans.
Linguistic Competence vs. Performance
Competence: knowledge of language in the mind. Performance: actual use of language (speaking, understanding).
Structural Ambiguity
- A sentence can have more than one structure, leading to more than one meaning.
The man saw the boy with the binoculars
Mental Representation
- Sentence structure has psychological reality, even if it is invisible.
- Speakers and hearers mentally build these structures.
Language and the Brain
- Language is primarily processed in the left hemisphere.
- Important areas:
- Broca’s area → speech production
- Wernicke’s area → language comprehension
Aphasia
- Language disorders caused by brain damage.
- Shows that language is localized and specialized.
Evidence for Biological Basis
- All normal children acquire language.
- Language impairments can occur independently of intelligence.
- Language develops similarly across cultures.
Critical Period Hypothesis
There is a biologically sensitive period for language acquisition. Late exposure leads to incomplete language development.
Language Acquisition in Children
Children acquire language:
- Rapidly
- Without instruction
- Effortlessly
Stages of Language Development
Babbling, One-word stage, Two-word stage, Telegraphic speech, Full grammar development.
Input vs. Innate Knowledge
- Children are exposed to limited and imperfect input, yet they acquire complex grammar.
- This supports the idea of innate linguistic knowledge.
First vs. Second Language Acquisition
- First language acquisition is: Automatic, Uniform.
- Second language acquisition: Harder, Influenced by age, exposure, and motivation.
Key Terminology
Behaviorist Psychology
An early psychological approach that viewed language as a set of learned behaviors formed through conditioning and stimulus–response associations, without reference to mental representations.
Creativity of Human Language
The ability to produce and understand an infinite number of novel sentences using a finite set of rules and words.
Decoding
The process by which the hearer reconstructs linguistic representations from the speech signal to recover meaning.
Descriptive Grammar
A description of the rules that speakers actually use when they speak their language.
Encoding
The process by which a speaker transforms an abstract idea into linguistic representations and finally into a speech signal.
Grapheme
The smallest unit of a writing system; a written symbol representing sounds or words.
Language Acquisition
The natural process by which humans acquire their native language, typically without explicit instruction.
Lexicon
The mental dictionary that stores words and information about their pronunciation, structure, and meaning.
Linguistic Competence
A speaker’s internalized knowledge of the grammar and lexicon of a language.
Linguistic Performance
The actual use of linguistic competence in producing and understanding sentences.
Morphological Rules
Rules that govern the structure of words and the combination of morphemes.
Phonological Representation
An abstract mental representation of the sounds of a sentence.
Prescriptive Grammar
Rules that specify how language should be used according to social or institutional standards.
Syntactic (Structural) Representation
The hierarchical organization of words into phrases and sentences.
Syntactic Rules
Rules that govern how words are combined to form sentences.
Thought
Abstract mental representations that exist independently of language.
Universality of Human Language
The idea that all human languages share fundamental properties, reflecting a biological basis.
Complementary Distribution
When sounds occur in different environments and never contrast.
Contrastive (Overlapping) Distribution
When sounds can appear in the same environment and change meaning.
Prosody
Patterns of stress, rhythm, and intonation.
Aphasia
A language disorder caused by damage to the brain, typically affecting production, comprehension, or both.
Brain Mapping
Techniques used to identify which brain areas are involved in specific linguistic functions.
Creole Language
A fully developed natural language that emerges from a pidgin when children acquire it as a first language.
Critical Period
A biologically determined window during which language acquisition occurs most naturally and completely.
Dichotic Listening
An experimental technique in which different auditory stimuli are presented simultaneously to each ear.
Acquisition Strategies
The methods children use to learn language, such as detecting patterns, forming hypotheses about rules, and applying learning principles. These strategies are unconscious and biologically guided.
Babbling
An early stage of language development (around 6–10 months) in which infants produce repeated syllables like ba-ba or da-da. Babbling is universal and reflects an innate capacity for language.
Mean Length of Utterance (MLU)
A measure of language development calculated by averaging the number of morphemes per utterance in a child’s speech.
Questions and Answers on Language Fundamentals
1. What are the two types of linguistic creativity that give us insight into the nature of human language?
First, humans can produce and understand an infinite number of novel sentences. Second, humans can use language to express any thought on any topic. These forms of creativity distinguish human language from animal communication systems.
2. Why is it important to distinguish between language and general intelligence? Between language and communication?
Language and intelligence are distinct because individuals can have normal intelligence but impaired language (e.g., specific language impairment), or impaired intelligence but relatively preserved language (e.g., Williams syndrome). Language and communication are distinct because communication can occur without language, such as through music, gestures, or visual art.
3. Why are linguists interested in describing rather than prescribing grammar?
Linguists aim to describe the actual grammatical systems speakers use, not to judge correctness. Descriptive grammar reveals how language is mentally represented, while prescriptive grammar reflects social conventions.
4. Why might some people think that one speech style or dialect is better than another?
People may associate certain dialects with education or social status. This is a social issue, not a psycholinguistic one, because all dialects are linguistically systematic and equally complex.
5. What determines the meaning of a sentence?
The meaning of a sentence is determined by the meanings of its individual words and by their syntactic structure.
6. What does it mean to say that structure is psychologically real, though abstract?
Sentence structure is not physically present in speech or writing, but it exists as a mental representation that speakers and hearers use to produce and understand meaning.
7. What is the distinction between linguistic competence and linguistic performance?
Linguistic competence is the mental knowledge of language, while linguistic performance is the actual use of that knowledge in real-time language processing.
8. What is meant by encoding and decoding in reference to sentence processing? What must the speaker and the hearer share?
Encoding is the speaker’s process of turning ideas into speech; decoding is the hearer’s process of reconstructing meaning from speech. Both must share the same language system (grammar and lexicon).
9. How do the views of contemporary psycholinguists differ from the views of the behaviorists from the first half of the twentieth century?
Behaviorists viewed language as learned behavior based on conditioning. Contemporary psycholinguists view language as an abstract, biologically based system represented in the mind/brain.
Questions and Answers on Biological Basis and Universality
1. What is meant by the claim that human language is universal?
Human language shares fundamental structural properties across all languages. This is critical because it suggests an innate biological basis for language.
What are phonotactic constraints?
They are restrictions on sound combinations and define which syllable structures are possible.
How is prosody used to determine sentence meaning?
Through stress, intonation, and rhythm, prosody signals emphasis, focus, and sentence type.
What does it mean that grammatical rules are psychologically real? How do metalinguistic abilities show this?
Rules exist as mental representations. Speakers’ ability to judge grammaticality reflects this mental knowledge.
14. What information is included in the lexicon? What is not included?
The lexicon includes phonological, syntactic, and semantic information of words. It does not include general world knowledge.
When psycholinguists say language is biologically based, do they mean that language has no social or cultural basis?
No. Language has a biological foundation but develops within social and cultural contexts. Biology provides the capacity, while experience shapes its use.
2. How does the universality of language support the view that language is biologically based?
Because all typically developing humans acquire language regardless of culture, suggesting an innate biological capacity.
3. Do communication systems taught to chimpanzees and gorillas falsify species specificity?
No. Although animals can learn symbolic systems, they lack the full grammatical creativity and generativity of human language.
4. Why is failure to acquire language considered pathological if hearing is normal?
Because language normally develops spontaneously; failure indicates a disruption of the biological language system.
5. What did Genie fail to acquire, and what did she acquire? What does this show about the critical period?
Genie failed to acquire normal syntax and morphology but learned vocabulary. This suggests that full grammatical acquisition requires exposure during the critical period.
6. What is meant by lateralization of language? How does aphasia support this?
Language functions are primarily localized in the left hemisphere. Aphasia typically results from left-hemisphere damage.
7. How does brain mapping show both lateralization and localization of language?
It reveals left-hemisphere dominance and identifies specific areas (e.g., Broca’s, Wernicke’s) responsible for distinct language functions.
8. Why can’t a split-brain patient name an object held in the left hand?
Information from the left hand goes to the right hemisphere, which lacks language production abilities.
Questions and Answers on Acquisition and Nativism
Why is language considered biological while writing is cultural?
Language develops naturally and universally, while writing systems are learned, variable, and culturally transmitted.
What is the nativist claim about language acquisition?
The nativist view argues that humans are biologically endowed with innate linguistic knowledge that guides language acquisition.
How does Universal Grammar assist language acquisition?
Universal Grammar provides a set of abstract principles and parameters that limit the possible grammars a child can acquire, making learning efficient.
What aspects of the linguistic environment matter? Which do not?
Important: availability of input and exposure. Not important: explicit correction or simplified grammar. Children succeed despite limited and imperfect input.
How do children acquire phonemic inventories?
Infants begin able to discriminate all phonemes, then specialize in those of their native language. This mirrors all of language acquisition: starting broad and becoming language-specific.
Do bilingual children differentiate their languages?
Yes. They maintain separate phonological and syntactic systems when the languages differ.
6. What principles help children learn vocabulary rapidly?
Whole object assumption, mutual exclusivity, fast mapping, and taxonomic assumption guide efficient word learning.
7. What kinds of variation are expected and not expected?
- Expected: rate of acquisition, vocabulary size.
- Not expected: violations of core grammatical principles.
8. Which morphemes are acquired early vs. late?
- Early: content morphemes and inflections.
- Later: abstract functional morphemes.
9. How do metalinguistic abilities develop and why are they important?
They develop gradually as children gain awareness of language as an object. They are crucial for literacy and academic language skills.