Chapter 4 Flashcards
When does brain development begin in utero?
Brain development begins within 18 days of conception
Neurological Development: Neuron Growth
- All neurons were developed by 2nd trimester of pregnancy
- Beginning at 4 months, neurons start organizing
- Initially they are overproduced and then half or more are pruned back when they aren’t organized into networks
- Myelinization begins after birth
- Cells begin communicating after birth
- Physical brain organization is under genetic control, but development can be environmental
Habituation: definition
- Becoming used to a stimulus
- After habituation, the stimulus does not elicit a significant response, so the infant can attend to new stimuli
Early Cognitive Development: Sensation definition
- The ability to register sensory information
- There’s competition from older, less novel stimuli
- Quantity and quality of sensation changes with birth
Which sensation is the first to develop in utero?
Touch is the first sense to develop in utero followed by sound and smell
Early Cognitive Development: Perception
Definition
-Using sensory information and previous knowledge to make sense of incoming stimuli
Early Cognitive Development: Motor Control definition
- Muscle movement and the sensory feedback informing the brain of the extent of that movement
- Begins at 7 weeks postconception
Reflexes: definition
Automatic, involuntary motor patterns (twitches, jerks, random movements)
Early Cognitive Development: Cognition definition
Mental activities involved in comprehension of information including:
- Acquisition
- Organization and storage
- Memory
- Use of knowledge
Brain Structure: Neuroplasticity
- Children can sustain brain damage, but recover
- Damaged abilities are assumed by other portions of the cortex
- Children with early brain lesions use a variety of alternative developmental pathways to preserve language functioning
How Experience Matters
- Synapse growth is highly dependent on experience
- Development is reliant on genetic and environmental effects
- The quality of experience in early development is critical
- Early learning lays a foundation for later learning – early intervention can significantly improve cognitive, linguistic, and emotional abilities
- See: critical period
How does institutionalization affect IQ in children under 2?
- Typically developing children institutionalized at birth have low IQ in comparison to typically developing children in high-quality foster care before age 2 (results in dramatic increase in IQ)
- Similar trend in language
- Critical period ~ 16-18 months of age
Prosody: definition and how infants use it
- The flow of language
- Infants use stress and rising and falling intonational patterns to discriminated word boundaries
- Soon after birth infants prefer their native language to other languages as they increasingly detect language specific prosodic (rhythm) patterns
- by 5 months, most infants respond to their own name
- by 6 months, they respond to “mommy” and “daddy”
In English, what percent of words in conversation have stress on the FIRST syllable?
80% of words in conversation have stress on the initial syllable
Sounds To Words: What is vocabulary size related to?
-Vocabulary size seems to be related to young children’s (26-32 months) ability to repeat phoneme combinations, especially in the initial position
What are infants phonologically capable of at birth?
At birth, infants are capable of detecting every phoneme contrast used in human languages.
What can infants discriminate at 5 months?
By 5 months, infants discriminate their own language from other languages with the same prosodic patterns.
What can infants discern at 9 months?
By 9 months, children are using prosodic and phonotactic clues to discern individual speech sounds in connected speech.
Reflexive crying and vegetative sounds: when do they develop and what are they?
- Develop around 0-2 months
- Reflexive vocalizations: cries, coughs, burps
- Vegetative sounds: grunts, sighs, clicks, and similar noises associated with activities such as feeding
Cooing and laughter: when do they develop and what are they?
- Develop around 2-4 months
- Cooing is considered a Quasi-resonant nuclei (QRN)
- Mostly nasalized vowels and nasal consonants
- Sustained laughter specifically develops around 16 weeks
Babbling and Vocal Play: when does it develop and what is it?
- Develops around 4-6 months
- Strings of sound segments, prolonged vowel- and consonant-like productions with variations in loudness and pitch
Reduplicated and variegated babbling: when do they develop and what are they?
- Develop around 9 months
- Reduplicated: similar strings of consonant-vowel pairs, especially the consonants (bababababa)
- Variegated: no repetition, variation of vowel-like and consonant-like babbles
Jargon: when does it develop and what is it?
- Develops up to 12 months
- Characterized by strings of babbled utterances modulated by intonation, rhythm, and pausing: sounds like a sentence, but it’s nonsense
Joint Attention: definition and importance
- Joint attention: the ability of two or more individuals to attend to the same thing at the same time
- Joint attention is important for learning and may be a precursor of focusing on a topic together in conversation
- There is a correlation between cognitive development and development of joint attention
How does attention affect language acquisition?
Infants with better attention are likely to acquire language more quickly due to better abilities to:
- Follow the gaze of others
- Engage in joint (shared) attention
- Track referents (subjects) of others’ speech
Importance of Memory
- Memory is vital for acquiring all forms of knowledge, including language
- Better memory = Better language
- As memory becomes less context bound (without the stimulus), a child can experiment and use objects and symbols in new ways
- With increased memory, a child can understand and produce more than one symbol at a time
How do recognition memory and recall relate to language skills?
Recognition memory and recall at 12 months predicts language skills at 36 months
Neurological Development: Anatomical Specialization in your Cortex
(when structures grow + develop in the brain)
- Brain cell differentiation began at 16th week of gestation
- In utero, growth occurs rapidly in brainstem and primary motor + sensory areas
- After birth there is rapid growth in the cerebellum and cerebral hemispheres, esp visual receptor areas
- Then the auditory receptors
- Left temporal lobe is large in fetal brain, continues to grow after birth and myelinizes later
- We don’t know when lateralization occurs
Neurological Development: Turning on and Getting Organized
How the Brain Activates
- at birth, brain is a jumble of neurons
- cells wait to establish purpose through activation
- activation means cells communicating, aka synaptogenesis
- when synaptogenesis occurs is super important
- genes are concerned w/ where functions are, experience takes care of the fine details
Neurological Development: Turning on and getting Organized
When different parts of the brain activate
- 2 months of age: the motor cortex more active (intentional movements develop)
- 3 months of age: visual cortex (focus), then limbic system (emotion and memory), then the cerebral cortex (higher thinking)
- second half of first year: frontal cortex and hippocampus (remembering stimuli, word association)
Information Processing: its role in learning
- 4 steps in info processing: attention, discrimination, organization, memory
- the first step in long-term learning is organization, and it’s important
- kids are continually taking in info, so organizing is important to being able to retain information and recall it later efficiently
- info placed in long-term storage and maintained by rehearsal, which is repetition
- integrative rehearsal is a special kind of rehearsal specific to transfer into long-term memory wherein new info is integrated into the structure of already-stored memory
Perception of Phonemes in Newborns and Infants:
How do newborns and infants perceive phonemes?
- Newborns are capable of discriminating different pitches and frequencies, especially in the human speech range
- Newborns respond to the human voice more than to environmental sounds
- Infants initially discriminate between all phonemes in human languages before becoming limited to only the sounds in their language
Perception of Phonemes in Newborns and Infants:
Timeline of phoneme perception
- Newborns perceive and discriminate all phonemes
- Between 6-12 months infants show a preference for vowel sounds in their native language
- By 8-10 months, infants’ perceptual abilities are restricted to their native language’s speech sounds
