Developmental Topic 1: Developing as a Learner

the studies and terms

Chugani 2001

Chugani 2001

Addresses: Brain Development

• Qualitative

• Case Study

• Convenience Sampling

Aim: to investigate effects of early deprivation on brain development

Procedure:

PET scans were used with 10 children (mean age 8.8) adopted by US families from Romanian orphanages.

-Orphans PET scans were compared to two control groups:

- 17 non-orphan adults (mean age 27.6)

- 7 age-matched children with focal epilepsy (symptoms confined to one hemisphere)

Results:

All 10 orphans showed significant deviations from the norm at the time of adoption

• At 1 year in the adoptive home, substantial “catch up” was reported in all orphans. At the time of the PET scans, adoptive parents described their children as having largely caught up with their peers, developmentally. There were continued concerns with attention difficulties such as staying on task.

• Compared to adults and the non-epileptic hemisphere of children with epilepsy, the orphans showed decreased glucose metabolism in some brain areas, particularly the prefrontal cortex, amygdala, hippocampus, and the lateral temporal cortex. These areas of the brain are known to be strongly interconnected and vulnerable to prolonged periods of stress.

Implications:

Researchers conclude that dysfunction of these brain regions may result from the stress of early deprivation and may be involved in the long-term cognitive and behavioral disturbances observed in some orphans.

Limitations:

Not controlled

Ethical considerations - undue stress/harm

Very few participants

Luby

Addresses: Brain Development

• Qualitative

• Meta-analysis - Use other people’s data

• Opportunity Sampling

Aim: To investigate whether the income-to-needs ratio experienced in early childhood impacts brain development at school age and to explore the mediators of this effect.

Procedure:

Children were assessed annually for 3 to 6 years prior to the time of an MRI, at which time they were evaluated on psychosocial, behavioral, and other developmental dimensions. Participants included healthy preschoolers and those with clinical symptoms of depression; all aged 3-6 years old and assessed for 5-10 years total.

Results:

Brain volumes of children’s white matter and cortical gray \n matter, as well as the hippocampus and amygdala volumes, were obtained using magnetic resonance \n imaging. Mediators of interest were caregiver support/hostility measured observationally \n during the preschool period and stressful life events measured prospectively. \n Poverty was associated with smaller white and cortical gray matter and \n hippocampal and amygdala volumes. The effects of poverty on hippocampal volume were \n mediated by caregiving support/hostility on the left and right, as well as stressful life events \n on the left. \n

Implications:

The finding that exposure to poverty in early childhood materially impacts brain development at school age further underscores the importance of attention to the well-established deleterious effects of poverty on child development. Findings that these effects on the hippocampus are mediated by caregiving and stressful life events suggest that attempts to enhance early caregiving should be a focused public health target for prevention and early intervention. Findings substantiate the behavioral literature on the negative effects of poverty on child development and provide new data confirming that effects extend to brain development. Mechanisms for these effects on the hippocampus are suggested to inform intervention

Limitations:

Reliability - they don’t have any control over the data and it’s unknown if CARDUD was followed through

Validity - only assessed annually, so nothing in between those years was measured

Samuel & Bryant 1984

Addresses: Cognitive development

• Quantitative

• Experiment

• Opportunity Sampling

IV(s): Age of child and stage in which the question was asked

DV(s): Accuracy of answers

Aim: to challenge the standard Piagetian conservation task by changing parts of the procedure

Procedure: 253 children 5-8 years (preoperational stage- concrete operational stage) from Crediton, Devon, UK were tested in their ability to conserve number (coins), volume (liquid), and mass (clay).

3 conditions used the same question: “Do each of these containers/rows/lumps have the same amount of liquid/number of coins/amount of clay or does one have more than the other?

1. The standard Piagetian task: the child was asked the same 2 questions (one before and one after the transformation of the material)

2. The child sees the materials before and after, then is asked one question after the transformation only

3. The child only sees the materials after they have been transformed and is then asked only one question. (fixed-array control)

Results:

-Asking only the post-transformation question (group 2) was typically easier for participants than the standard Piagetian task (group 1)  and the fixed-array control (group 3)

-Age: there was a significant difference between every age group, the older groups doing consistently better than younger groups

-Materials: the number task was significantly easier than the mass and volume tasks

Implications: Older children have better cognitive function

Limitations: This study’s age group could have been wider

Paulus

Addresses: Cognitive Development

BOTH qualitative and quantitative

Aim: to investigate the relationship between prosocial behavior in infancy along with cognitive and social skills with sharing behavior

Procedure:

A longitudinal study with 72 children from white, middle-class families in urban areas of Germany were tested at the ages of 7 months, 18 months, 24 months, 30 months, 48 months, and 60 months.

Measures:  Cognitive Development: Goal-encoding, working memory

Social Development: instrumental helping, empathic reasoning, gift delay, inhibitory control, perspective taking, and sharing behavior.

Results: Sharing= prosocial play with peers* (the role of peers and play)

• Found a relationship between delay of gratification at 24 months and inhibitory control at 30 months with sharing behavior at 5 years.

• Found a relationship between distress understanding at 24 months and sharing with friends at preschool age

• Found a relationship between goal encoding at 7 months and sharing with a disliked other at 5 years

Implications: *Overall, shows relationships between object manipulation and pretend play stages

*Supports Vygotsky’s theory of cognitive development as interconnected with sociocultural factors / the environment

The four stages of brain development

1. Neurogenesis: the birth of neurons, complete in gestation (conception-birth)

2. The migration of neurons to their correct location along neural pathways (9 weeks after conception)

3. Differentiation: development of connections between neurons (rapid growth conception-2 years)

4. Pruning: elimination of these connections as well as neurons themselves; increases efficiency in the brain (rapid pruning age 1 through the end of adolescence; another spurt of pruning in old age)

(biological & sociocultural)

Piaget’s theory of cognitive development

proposes all children pass through developmental stages of logical thinking, in the same order, regardless of person/culture

1. Sensorimotor Period (0-2)

2. Preoperational Period (2-7)

3. Concrete Operational Period (7-11)

4. Formal Operational Period (11+)

*Promoted the concept of universal development

Within each stage:

Assimilation: learning new information to add to existing schemas

Accommodation: learning to incorporate new realities into existing schemas in order to function in the world

Equilibration: mental balance attained through assimilating new experiences into mental schemas

Vygotsky’s theory of cognitive development

explains cognitive development as a process of internalizing culture through language and interaction with more knowledgeable peers and adults

three levels:

1. Cultural: children inherit cultural tools from society(ie. signs, language)

2. Interpersonal: interaction between culture and the individual; experiences of socialization lead children towards self-sufficiency

3. Individual: switch from external regulation to self regulation

*learning should be one step ahead of development = ZPD

Schemas

mental representations of organizational structures of all things

*the main change/growth in a child’s cognitive development