Lecture 3 Flashcards
Piaget’s stage theory
This is a stager theory. You can’t develop to a later stage without having developed through all the preceding stages first
Sensorimotor - 0-2 years - intelligence in action. Child interacts with environment by manipulating objects
Pre-operational - 2-7 years - thinking dominated by perception - egocentrism
Concrete operations - 7-11/12 years - logical reasoning applied only to objects that are real pr in view
Formal operations - 11/12 years + - can thinking logically about abstract ideas
Stage 1: sensorimotor
Key mile stone: object permanence
Sensory contact understanding
The child explores the world surrounding them using it’s senses
I totally sucking/grasping reflex and moving onto reaching for objects out of reach
We can research this stage through habituation/ look time, eye tracking and search
Object permanence
- what do infants know about objects that are occluded?
- do they understand that a partially hidden object continues to exist?
They used studies with images of green rods that were either complete or broken and used eye tracking to measure how long they looked at them
They dishabituate to the broken rod, i.e. they look more at the broken rod than the complete rod
Dishabituation is interpreted as meaning babies expected to see a complete rod
Stage 2: pre-operational
Children in the pre-operational period only direct attention to limited aspects of a given situation
They have an egocentric view of the world
Three mountains task:
- children of 4 or 6 years often chose the view that they themselves could see, not the doll’s view
- not until 8 or 9 years that they could confidentially work out what the do;l could see
- Piaget interpreted this as egocentrism - he said that the child cannot decline from their own view to work out the doll’s view
- Piaget & Inhelder concluded that young children are still ‘rooted in their own position’ - they have an egocentric perspective of the world
Stage 3: concrete operational
Key mile stone: conservation
Children begging to reason logically about the world
Begin to solve conservation problems, but their successful reasoning is largely ;i tied to concrete situations
However, thinking systematically remains difficult
Conservation tasks:
- do children understand that if liquid is transferred from a smaller container to a bigger container that it is still the same amount of liquid?
- don’t tend to understand till this stage
Stage 4: formal operational
12 years onwards
Begin thunk abstractly
Consequences of Actions
Moral reasoning
Think more like adults
Critique of Piaget’s theory
Piaget’s theory understates the contribution of the social world to cogntive dveelopment
- his tasks are culturally biased
- schooling and literacy affect rates of development
- formal operational thinking is not universal
His theory is vague about the cognitive processes that give rise to children’s thinking and about the mechanisms that produce cognitive growth
Key terms for brain development
Maturation - changes driven by genetic processes according to a specific timetables (the nature side)
Critical periods - time-limited windows when specific experiences must occur to drive max development. Learning is ineffective outside these time windows
Sensitive periods - time-limited windows when specific experiences have their largest effects. Learning can still be effective outside those time window as
Experience-expectant - processes that utilise environmental information that is highly reliable for all members f the species (e.g. hearing a language)
Experience-dependent - processes that utilise environmental information that can vary across individuals (e.g. the language that was heard)
Brain development
The brain reaches approx 90% of adult volume by 6 years
Early postnatal period: level of connect Vigny bear exceeds that of adults
This is gradually pruned back via competitive processes that are influenced by the experiences of the organism
Structural changes in gray and white matter continue theough childhood and adolescence
These changes in structural changes in function organisation
- this is also reflected in behaviour
Key terms for developmental cognitive neuroscience
Synaptogenesis - neurones form connections, called synapses, with other neurones. This happens rapidly during early brain development - the ‘wiring’
Synaptic pruning - eliminating unused or weaker synapses in the brain. It occurs that synaptogenesis and is part of he brain becomes more efficient - occurs especially during adolescence
Grey matter - contains most of the brain neurones and synapses
Myelination - dating the axons with a fatty substance (myelin). Acts as insulation on electrical wires, speeding up the transmission of signals between neurones. Crucial for connectivity and effiecent brain function
Cell death - natural and controlled process where cells die off as part of normal development - efficient brain function
Gogtay et al (2004)
Gray matter density during childhood and adolescence
4-21 years, scanned every 2 years
It takes a long time for the brain’s communication lines to mature - keeps maturing into 20s
Maturation of low-level sensory snd motor corticles occurring por to prefrontal and temporal corticles, which are involved in the higher-level cognition and regulation of behaviour
Sensitive periods
Times in development when heightened neuroplasticy leave the brain susceptible to environmental infeunce
Environmental input can lead to a series of developmental cascades
Socioeconomic status and brain strcutre
Rakesh et al (2021)
Synaptic review: neural correlates of SES in youth samples across neuroimaging studies
SES = possession of material and non-material resources - parental education, occupation and income
Low SES linked to reductions in gray matter volume, thickness and surface areas
Especially in frontal and temporal regions
Cognitive ageing and dementia
‘For some individuals presenting with dementia, impairment may be attributed primarily to shallow trajectories of childhood cognitive development, rather than particularly steep trajectories of adult cognitive decline’ - Tucker-Drob et al (2018)
Brain function declines once adulthood hits
Dementia
An neurodegenerative disorder
10-15 years prior to reaching a dementia stage, cogntive decline is detectable
Dementia is linked to
- genetic disposition
- life style
- habits
- environmental exposures across the lifespan
Evidence to support this:
- higher levels of stimulation (parental and environmental, learning) generates increased synaptic proliferation, a denser cortex, greater intellectual flexibility
- reinforcing a neural resistance to a natural ageing brain or damage
Factors across the lifespan
Perinatal neurodevelopment
- prenatal malnutrition and reduced birth weight have adverse effects of cogntive functioning - when a harmful event occurs, it interferes with typical growth and neuroplasticity
Adverse childhood experiences:
- environmental stimuli and experiences shape neural pathways - sensory periods for sensory perception, motor skills, language acquisition vulnerable to external influences
- stress - reductions in amygdala volume and heightened responsiveness to threat
Adolescence:
- sensitive periods of social, emotional amd cognitive development - undergoing plasticity based on the experinces of the individual
But factors aren’t a definite
Not all individuals that are exposed to risk factors will develop dementia because of brain resilience
- the brain’s ability to adapt to or recover from stress, trauma and damage
Individual differences in brain structure and function that is built across the lifespan
Management of risk factors across the lifespan to minimise dementia incidences
Example in Tom et al (2023)
- ppts born between 1893-1949
- followed from 1994-2015
- at enrolment, ppts were dementia free, visits every 2 years until diagnosis of dementia, death or withdrawal from study
- measures taken - ppts height, education level, childhood financial stability, childhood household density, early life environment
- later life vacua’s risk factors of dementia
Findings:
Ppts classified as
- pre WW1 (1893-1913)
- pre-great depression (1921-1928)
- Great Depression (1929-1939)
- WW2 and post war (1940-1949)
Age-dementia link:lower for those brown in 1929+ compared to those born earlier
Indications that more advantaged early-life environment was associated with lower dementia incidence, it could not explain the link between cohort and dementia incidence
Another Example: Xiang et alm (2022)
15,133 ppts from the health and retirement study (1998-2016)
6 childhood adversity indicators:
- grade retention
- parental substance abuse
- physical abuse
- trouble with the police
- moving due to financial hardship
They found some aspects of childhood adversity continue to harm cognitive functioning later in life, whilst some events may have the opposite effect, with evidence of heterogeneity across gender and race
