age two - 75 % developed
age five - 90 % developed
age seven - 100 % developed
Ψ At about the age of 5, children show important gains as a result of growth in the corpus callosum, a band of nerve fibers connecting the right & left hemispheres of the brain. This development of
connectiveness gives them the ability to read!
Ψ Lateralization: a.k.a. "sidedness." Each hemisphere of the brain performs basically the same motor & sensory functions, but each hemisphere’s association area is specialized for different operations, a phenomenon known as lateralization.
• The left hemisphere shows superiority in tasks involving speech, language, reading, & writing.
• The right hemisphere functions better on tasks involving spatial construction, facial recognition, nonverbal imagery, sense of direction, musical recognition, & emotional states.
Ψ The Prefrontal Cortex is the seat of higher-order cognition, including planning & complex forms of goal-directed behavior. The "executive" of the brain.
Benefits of maturation of this part of the brain (ages 2 - 6) follow.
• Temper tantrums subside.
• Sleep becomes more regular.
• Uncontrollable laughter or tears become less common.
• Emotions become more nuanced & responsive to
Ψ Another function of the prefrontal cortex is to focus attention & thus curb impulsiveness. Impulsiveness & perseverance ( to stick to just one thought or action - the
opposite of impulsiveness) are behaviors caused by immaturity of the prefrontal cortex. During the preschool years, brain maturation (innate) & emotional regulation (learned) decrease both impulsiveness & perseverance.
Limbic system is an area of the brain that is crucial in the expression & regulation of emotions. The three major parts of the limbic system follow.
• Amygdala: A tiny part of the brain that registers emotions, particularly fear & anxiety.
• Hippocampus: Part of the brain that is a central processor of memory, especially
the memory of locations.
• Hypothalamus: A brain area that responds to the amygdala & hippocampus to
produce hormones that activate other parts of the brain & body.
• The HPA Axis: involves the hypothalamus, pituitary, & adrenal glands. This complex system is responsible for effectively handling stress by regulating the production of cortisol, neurotransmitters & key hormones. When the HPA axis is not functioning correctly, a variety of neurological symptoms develop, such as anxiety, depression, intolerance to stress, suicidal ideation, sleep disturbance, & mood disorder.
Lifespan Growth & Development|
Robert C. Gates