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Section B
Neurodevelopment
Timeline of Brain Development
Adapted from: Andersen. (2003). Neuroscience and Biobehavioral Reviews, 27,3–18.
3
How Does the Infant Brain Become the Adult Brain?

Overproduction

Selective elimination
4
Neuronal Branching
Adapted by CTLT from (1998). Diamond, Hopson, Scheibel. Magic Trees of the Mind.
5
Neuronal Branching as We Age
6
Synaptic Density and Age
7
Henry Kissinger
http://www.flickr.com/photos/darthdowney/2680488605/. Creative Commons BY-NC.
8
Synaptic Density and Age
9
Brain Maturation

Improved brain function
-  Increased
efficiency of local
computations
-  Increased speed of
neuronal
transmission
10
Frontal Lobe

Executive function

Planning

Reasoning

Impulse control
http://en.wikibooks.org/wiki/User:Jherding. Creative Commons BY-SA.
11
Dorsolateral and Ventromedial

Thinking ahead and inhibition
of impulsive responses

Regulation of emotions;
weighing risks and rewards;
learning from experience
12
Brain Maturation and Behavioral Development

Implications of brain maturation for behavioral development
-  Changes in pre-frontal cortex (PFC) should be reflected in
improvements in executive functions
  Future orientation (e.g., thinking ahead, consequences)
  Response inhibition
  Planning
  Managing risk and reward
13
Brain Development and Environment

Brain development occurs within the context of the environment

Toxic environments impede normal brain development
14
The Process of Toxic Stress
15
Persistently Elevated Cortisol in Childhood

Decreased synaptic and dendritic density early in life

Decrease in pubertal hormones

Diversion of brain resources away from learning to survival (e.g.,
fight or flight)

Interruption of normal neurotransmitters (e.g., serotonin)
16
The Neurodevelopmental Impact of Chronic Abuse

Diminished hippocampal volume

Impaired development of frontal lobe (executive functioning)

Diminished emotional control

Problems with social relations and academic performance
17