1. Cognitive Development in Children
Ms. Carmelitano

2. Brain Review: 4 Lobes Frontal Lobe- Parietal Lobe- Occipital Lobe-
reasoning, planning, parts of speech, movement, emotions, impulse control and problem solving
Parietal Lobe-
movement, orientation, recognition, perception of stimuli
Occipital Lobe-
visual processing
Temporal Lobe-
perception and recognition of auditory stimuli, memory, and speech

4. Brain Review
Dendrite: the threadlike extensions of a neuron; They are the receptive site of the neuron and branch out to make connections with the dendrites of other neurons
Dendritic Branching: When a neuron grows more dendrites, creating increased connections between nerve endings
This allows for tasks to become easier, and more efficiently completed

6. Natural Reflexes At birth a baby has natural reflexes such as: Sucking
Grasping
Basic visual and auditory abilities
They are prepared for social interaction
Babies respond to human faces from birth
Babies exchange sounds and non-verbal signals with their primary caregiver
This may be due to mirror neurons

7. Brains of newborns
There are more than a trillion nerve cells working in the brains of infants
They are supported by a trillion glial cells: 90% of the cells in the human body (These are cells which support neuron function)
Synaptic growth in the brain is more significant in the first year of life than any other time in person’s life
However, brain development will continue until late adulthood
This is called neuroplasticity: the ability of the brain to develop and change in response to the environment
Brain activity increases with synaptic growth
Why do you think synaptic growth is so rapid in the early stages of life?

8. Pet Scan
A positron emission tomography (PET) scan is an imaging test that helps reveal how your tissues and organs are functioning. A PET scan uses a radioactive drug (tracer) to show this activity.

9. Chugani 1999 Modern technology can study brain development
Procedure: Performed a PET scan of glucose metabolism in the brains of newborn human babies
Found: Little activity in the cerebral cortex: associated with high level functioning
There is high activity in the brain stem and thalamus, associated with inborn reflexes
The limbic system, amygdala, hippocampus, and cingulate cortex (associated with memory, emotional processing, and bonding) are somewhat active
Conclusion: This supports the reason why babies have a high capacity to observe and read emotional content of human faces and to communicate with facial expressions
But they do not have the same abilities to think and plan

11. Bachevalier 1999
Lesioned the highly active areas of the brain, Chugani discovered, in new born monkeys
The monkeys gradually lost the capacity for social behavior
Eye contact decreased, and the animal showed blank facial expressions
This is also found in children who are autistic
The conclusion of observations like these is that reading facial expressions is to some extent an innate capacity which can be lost due to brain damage

12. Brain Development
From age 6-9 months the frontal and prefrontal areas of the cortex begin to function more fully due to the growth and myelination of neurons (the formation of the myelin sheath – which enables nerve cells to transmit information faster and allows for more complex brain processes)
The hippocampus will also develop during this time
This plays a role in memory
The cerebellum will develop which controls body movements
This will increase the ability for more complex motor behavior and increase the ability to learn
Chugani shows a steady increase in glucose metabolism in these areas, that will continue until age one
Glucose metabolism will increase and reach adult levels around the second year of life

13. Pruning
Pruning is the process of weeding out unnecessary neural connections and strengthening the important ones, based on the child's experiences.
The most rapid pruning happens between about age 3 and age 16
Different areas of the brain undergo pruning during different sensitive periods
Experiences during infancy and childhood form the connections that shape the development of the brain.
Pruning is a key part of brain development because it eliminates the connections that are not used often enough.
Pruning provides room for the most important networks of connections to grow and expand, making the brain more efficient.
They create unique connections for each individual depending on the environment in which they live

15. Memory, Attention, and the brain
Gelman 2003
Argues that by the age of 2, children have the ability to understand new, non-obvious features of things
Because of this, they will be more likely to pay attention to objects with bright colors, or “different,” “fun,” noises

16. Memory, attention, and the brain
Bauer and Pathmann 2008
The weight of the brain increases from 25% of its adult weight at birth, to 75% of its adult weight by 2 years old
The hippocampus forms prenatally
However the dentate gyrus, which links the regions of the brain, will not be fully developed until months old and the pre-frontal cortex will not be fully formed until 2 years old
Result: Infantile amnesia – Children have the ability of conscious memory at birth, but cannot recall explicit memories until age 3
This is why you have few – if any – memories of your life before your third birthday
Pres-school brains fade faster than older brains when it comes to explicit memories
Stein 1995
Children under the age of three have the ability to retain and later recall implicit memories, because the amygdala forms earlier than the hippocampus.
Memories for doing implicit tasks will also develop sooner
This is why a baby can “remember” how to balance and walk, but may not remember their mother’s birthday.
Howe 1995:
Memory requires storage and retrieval. Children from ages 1 to 11 have problems in storage.
The average 3 year old can repeat two digits in succession and at age 7 can repeat four.

17. The Brain during adolescence
When children become teenagers, they begin to develop the ability to think in more abstract ways
Brain changes are less dramatic than in earlier life, but still are important
Reorganization and myelination of the higher brain centers, like pre-frontal cortex continue until age 20
This is why people become better able to strategically plan as they get older
Impulse control in the prefrontal cortex is the last to mature around 20 years old – Giedd 2004

18. Giedd 2004 Longitudinal study Gave MRI to children every 2 years
Found: 95% of the brain structure is formed when children are 5 or 6
Areas in the prefrontal cortex appear to grow again just before puberty
Conclusion: Different parts of the brain mature at different times