Introduction to Language Development and Phonology Flashcards

Phoneme: The smallest contrastive unit of sound in a language.
Allophones: Contextual variations of a single phoneme that do not alter word meaning.
Word Structure: Words can be broken down into syllables (stressed and unstressed), which are further split into onset and rime.
Phonotactic Knowledge:
- Refers to the innate understanding of language-specific constraints and rules governing permissible sound sequences.
- Example: The sound blend $\text{"tz"}$ (e.g., in the name Zipporah) is not a native onset blend in English, leading English speakers to omit the $\text{"t"}$ sound, whereas Hebrew allows this combination.
- Develops rapidly within the first year of life as neural networks reinforce frequently heard sound patterns.
Phonological Ability:
- The ability to manipulate speech sounds (e.g., sound deletion, segmentation, blending).
- Dependent on underlying phonotactic knowledge and early exposure.

Efficiency in Speech Production:
- Phonological rules are unwritten and naturally adopted to optimize biomechanical efficiency in speech.
- Phenomena like co-articulation and assimilation prevent the system from needing to articulate each phoneme in isolation.
Plural Marking Rules ( $\text{/s/}$ vs. $\text{/z/}$ ):
- Graphemic Representation: Both marked visually by the letter s.
- Phonetic Realization:
- Following a voiced consonant: Produced as a voiced $\text{/z/}$ (e.g., rugs $\rightarrow$ $\text{/g/}$ is voiced).
- Following a voiceless consonant: Produced as a voiceless $\text{/s/}$ (e.g., bikes $\rightarrow$ $\text{/k/}$ is voiceless).
- Developmental Significance: Children acquire plural markers early due to their concrete nature without explicit instruction on vocal fold vibration.
Past Tense Marking Rules ( $\text{/t/}$ vs. $\text{/d/}$ ):
- Graphemic Representation: Marked visually by -ed.
- Phonetic Realization:
- Following a voiceless sound: Produced as $\text{/t/}$ (e.g., helped).
- Following a voiced sound: Produced as $\text{/d/}$ (e.g., jogged).
- Finite Marking: Refers to verbs marking grammatical tense. Regular past tense is typically mastered by ages 4–5. Children with Specific Language Impairment (SLI) frequently struggle with finite marking.

Generative Grammar vs. Memory:
- Children do not simply memorize word pairs; they extract and apply rule systems to novel vocabulary.
The Wug Test (Jean Berko Gleason):
- A classic experiment proving rule application by presenting pseudo-words to young children (e.g., "This is a wug. Now there is another one. There are two of them. There are two [wugs].").
- Demonstrates productivity in applying morphological markers for plurals, past tense, possessives, and progressive verbs (boding, gutches, Bix's).
Linguistic Diversity & Code-Switching:
- Typically developing children adapt flexibly to language environments (e.g., alternating between dialectal home patterns and Standard American English in academic contexts).

Pre-natal Foundations:
- By 24 weeks gestation, the fetus brain has nearly its full complement of billions of neurons, forming connections at a rate of up to $2.0 \times 10^6$ connections per second.
- The auditory system becomes functional around 20 weeks gestation, allowing response to maternal voice and environmental acoustics.
Two Phases of Brain Wiring:
1. Genetic Blueprint: Defines broad neural pathways and structural organization (e.g., routing visual information to visual cortex, auditory to auditory cortex).
2. Activity-Dependent Pruning ("Use It or Lose It"):
- Infants begin with "exuberant connectivity" (roughly twice the synaptic connections of an adult).
- Experience acts as a sculptor: frequently activated connections are stabilized and strengthened, while unused connections undergo synaptic pruning.

Perception Precedes Production:
- Comprehension and perceptual sensitivity consistently precede productive vocabulary and speech output.
Developmental Timeline:
- 0–2 Months: Strong attunement to maternal voice and prosody due to prenatal auditory experience, crucial for bonding and survival.
- 3 Months: Sensitivity to supersegmentals (stress patterns, intonational pitch changes) and engagement in vocal turn-taking (early pragmatic development).
- 5 Months: Imitation of specific speech sounds.
- 6 Months: Discrimination of subtle phonemic differences, including cognate pairs differing by single features (e.g., voicing in $\text{/b/}$ vs. $\text{/p/}$ ).
- 7–12 Months: Recognition of high-frequency environmental words (e.g., bottle, mama, nap); ability to execute simple receptive commands prior to producing first words at ~12 months.

Citizens of the World:
- Infants under 6–8 months can discriminate all phonetic contrasts across all natural human languages.
Culture-Bound Listeners:
- Between 8–10 months, infants narrow their perceptual boundaries to match the statistical distribution of their ambient native language (e.g., English infants improve on $\text{/r/}$ – $\text{/l/}$ contrasts while Japanese infants decline).
Statistical Learning Mechanism:
- Infants track frequencies and probability distributions of speech sounds during natural exposure, fundamentally altering neural representations.
The Social Brain Constraint:
- Experiments exposing American infants to Mandarin demonstrated that live human interaction yielded phonetic learning equivalent to native Taiwanese infants.
- Equivalent exposure via television or audio-only media resulted in zero statistical learning, proving that social interaction is required to trigger language