the developing brain

Question 1

history: middle ground perspective

Answer 1

interaction between environment and genetic factors

eg. Piaget/neuroconstructivism

Question 2

what are the different theories within the nature/nurture debate?

Answer 2

blueprint analogy

predetermined development

probabilistic development

Question 3

describe Gottlieb’s different views of development

Answer 3

Predetermined development

Probabilistic development

Question 4

what is Predetermined development?

Answer 4

genes–> brain structure–>brain function–>experience

Question 5

what is Probabilistic development?

Answer 5

genes<–>brain structure<–>brain function<–>experience

effects of genes on brain structure themselves are probabilistic: specify approx. how and where neurons develop

variation, not copy = MZ twins

Question 6

what are the steps within prenatal brain development?

Answer 6

cell division

cell specialisation

neural tube formation

neural tube differentiation

Question 7

neural tube formation

Answer 7

proliferative zones: neurons and glial cells produced

250,000 neurons produced/min

neurons migrate to final location

Question 8

what occurs during neural tube formation?

Answer 8

develops into spinal cord and brain

Question 9

what structural features emerge from constraints?

Answer 9

• folded cortex emerges from having lots of neurons
• pattern of gyri/sulci pulled into shape by tension of axon bundles
• Hebbian learning: Spontaneous electrical activity enables networks to form eg. retina

Question 10

what causes the postnatal increase in brain size?

Answer 10

synaptogenesis

myelination

glial cell proliferation

Question 11

what is plasticity?

Answer 11

experience
dependent change in neural
functioning

can lead to small but observable structural changes

Question 12

how is plasticity evident in the brain?

Answer 12

increased grey matter: new synapses, dendrites, axon collaterals, glia cells

Question 13

what is functional brain development?

Answer 13

prenatal brain
damage can lead to major reorganisation of
tracts

eg. AH with no right hemisphere

Question 14

how is functional brain plasticity limited?

Answer 14

Spontaneous electrical activity enables networks to form
intrauterine – connections not fully lost

Opportunities for major reorganisation are time-limited =critical or sensitive periods

Question 15

what is filial imprinting?

Answer 15

the process
by which young animals learn
to recognise the parent
- 15hrs-3 days
- movement is crucial

Question 16

what are the 2 main features of critical and sensitive periods?

Answer 16

1. Learning takes place within a limited window
   o But opportunity can be extended in lack of experience
2. This learning is hard to reverse by later experiences (but can generalise to similar objects) (preference can be changed after)

Question 17

phenomic discrimination between ‘r’ and ‘l’ is an example of…

Answer 17

critical and sensitive periods

Question 18

what are the explanations of c+s periods?

Answer 18

genetically programmes synaptogenesis followed by reduced plasticity

closure of window initiated by learning

Question 19

what is the empiricist view on innate knowledge?

Answer 19

newborn mind is a blank state

Question 20

what is the nativist view on innate knowledge?

Answer 20

we are born with some knowledge

Question 21

what is the more modern view on innate knowledge?

Answer 21

Innate = readiness to learn

Knowledge or behaviour that arises in the absence of appropriate
experience

eg. cat visual cortex
eg. preferences

Question 22

prenatal ultrasound shows:

Answer 22

structure: different types of tissue have different physical properties

creates STATIC maps

Question 23

How can we
investigate
brain
development?

Answer 23

prenatal ultrasound

prenatal MRI

behavioural methods

Question 24

from behaviour, we can infer:

Answer 24

brain development

eg. Preferential looking paradigm

Question 25

what is meant by 'functional' in neuroscience methods?

Answer 25

temporary changes in brain physiology associated with cognitive processing (e.g. fMRI)

Question 26

what is the problem of functional neuroscience methods?

Answer 26

Usually, we ask participants to perform some kind of task or to sit/lay still and look at images Infants won’t perform tasks and they won’t even stay still

Question 27

what are functional neuroscience methods that can be used with infants and young children?

Answer 27

Electrophysiological response (electromagnetic fields in brain) eg. EEG/ERPS Haemodynamic response (brain blood supply) eg. fMRI, fNIRS

Question 28

infant EEG

Answer 28

Infant friendly EEG systems/solutions that allow quick installation Infant friendly stimuli More breaks during the study

Question 29

infant vs adult ERPs

Answer 29

Some adult ERP peaks are present in infants, but delayed: e.g. visual ERPs eg. N1/N290: Perceptual and/or face specific component

Question 30

some ERP components only present in infants and toddlers:

Answer 30

Negative Central peak Typically peaks between 300- 700 ms after stimulus onset Reflect attention Larger peak reflect higher attention

Question 31

why is fMRI not ideal for infants?

Answer 31

Highly sensitive to motion artifacts Loud, restrictive environment but some recent attempts eg. face specific activity in the brain

Question 32

fNIRS

Answer 32

measures BOLD signal (blood oxygen-leveldependent contrast) using near infrared spectrum Skin, tissue, and bone are mostly transparent to NIR light Measures the concentration changes of oxyHb and deoxyHb focally, related to brain activity

Question 33

how to compute BOLD response?

Answer 33

from the difference between emitted and detected NIR Hb and deoxyHB absorb of NIR

Question 34

NIRS vs fMRI

Answer 34

NIRS can be an appropriate substitute

Question 35

NIRS cons

Answer 35

fNIRS has lower spatial resolution Only the surface of the cortex can be imaged Often only a few sensors are used above a certain brain area

Question 36

NIRS pros

Answer 36

Portable More tolerant of movement