Neural and Linguistic Development

Question 1

Embryonic Stages

Answer 1

Pre-embryonic
Embryonic
Fetal

Question 2

Pre-embryonic stage

Answer 2

Conception - 2 weeks 
Ovum begins cell division 
Becomes blastocyst 
Outer layer = placenta 
Innermass = embryo (ectoderm, endoderm, mesoderm)

Question 3

Embryonic stage

Answer 3

End of week 2-8

Organs are formed

Question 4

Fetal stage

Answer 4

8 weeks - birth

Nervous system develops more fully and myelination of neurons begin

Question 5

Ectoderm

Answer 5

Becomes sensory organs, epidermis, nervous system

Question 6

Endoderm

Answer 6

Gut, liver, pancreas, respiratory system

Question 7

Neural tube formation

Answer 7

1. longitudinal thickening of ectoderm; neural plate forms on surface of embryo
2. neural groove forms - edges of plate start to fold
3. Day 22 - folds touch to form neural tube
4. cells next to tube separate - remaining ectoderm forms the neural crest
5. Day 26 - tube differentites into mantle and marginal layer

Question 8

Mantle layer

Answer 8

Inner wall of neural tube

Becomes grey matter

Question 9

Marginal layer

Answer 9

Outer wall of neural tube

Becomes white matter; axons and glial cells

Question 10

Ventricular system

Answer 10

Derived from the neural canal

Filled with CFS

Question 11

Timing of Development - first 8 weeks

Answer 11

something goes wrong - results in defectively designed structure system

Question 12

Teratogenesis

Answer 12

Cogential malformations in embryo/foetus

Question 13

Earlier teratogenesis

Answer 13

major congenital defects

Question 14

Later teragonesis

Answer 14

Minor defects, functional malformation

Question 15

Neural tube defects

Answer 15

Incomplete development of the neural tube
Occurs between 17-30th day after conception (critical period)
Related to folic acid deficiency, genetics, maternal diabetes, SES

Question 16

Cerebral Palsy

Answer 16

Impairment in voluntary movement
Maldevelopment of brain, prenatal/during birth/shortly after birth brain damage
Pre-term, low birth weight at higher risk
Caused by lack of oxygen, infection, impaired rate of growth during pregnancy/early years of life

Question 17

Cellular level development

Answer 17

Progressive developmental processes balanced by regressive processes that remodel the NS
Epithelial cells lining the neural tube divide to produce neurons and glia

Question 18

Progressive processes

Answer 18

Cell proliferation, migration and growth, extention of axons to target cells, formation of synapses, myelination of axons

Question 19

Stages of Brain Development

Answer 19

1. cell birth (neurogenesis gliogenesis)
2. cell migration
3. cell differentiation
4. cell maturation (dendrite and axon growth)
5. synaptogenesis (formation of synapses)
6. cell death and synaptic pruning
7. myelogensis (formation of myelin)

Question 20

Locke’s Theory of Neurolinguistic Development - Overview

Answer 20

Processes orient child to language
Responsiveness to facial/vocal activity - influenced by genetic factors, early experience, supported by neural pre-adaptions
Each phase occurs in a fixed and overlapping sequence, commitment of neural resources

Question 21

Phase 1 - Vocal Learning

Answer 21

Strongly oriented to face and voice
Specialisation in social cognition - orients child to communication
Heavy genetic influence

Question 22

Phase 2 - Utterance Acquisition

Answer 22

Rote learning 
Use of formulaic phrases; mimic length, stress pattern, intonation
Correct forms of irregular syntax 
Stored in prosodic type memory
Right hem. - emotional/social
Storage limitations 
LH not involved

Question 23

Phase 3 - Analytical and Computational

Answer 23

18-20 months
Stored utterances (critical mass) trigger analytical mechanisms
Structure analysis system - locates recurring elements within/across utterances

Question 24

Phase 4 - intergrative and elaborative

Answer 24

Analytical and computational ability integrated with acquisitive system = growing lexicon
Increasing lexical capacity - syntactic processing becomes more automatic
= appropriately organised grammatical system and lexicon; used with high degree of difficulty
Pragmatics
Social cognition
Word knowledge

Question 25

Individual Networks and Wiring

Answer 25

Sequence of development/stabilisation of synapses - functional behaviours
Formation, elimination and stabilisation of synapses depend on experiences