-
-
Period: to
Introduction Video
-
Period: to
First trimenster
The brain develops rapidly and makes up nearly half of the fetus’s weight. For comparison, by the time the baby is born, the brain is only 10 percent of its body weight. In the first trimester, the brain will grow millions of neurons, which connect across synapses to direct movement and growth. -
Neurulation
the embryo begins to organize itself into a three-layered, spherical structure (forming the Neural Tube) -
Neural Plate Developes
A couple of weeks after conception the embryo forms a neural plate, this is the base for the nervous system, and as it grows it will begin to fold onto itself forming the brain at the top of the tube. -
The Neural Tube Closes
Week 5 or 6:
The neural tube closes and the brain is separated into 3 parts. (Front brain, midbrain, and hindbrain) These parts will develop into the specialized parts of the brain, and the cerebrum will fold into the left and right halves of the brain.
After the neural tube closes the brain will grow at a rate of 250,000 neurons per minute for the next 21 weeks.
brain development resourse -
-
Period: to
Second Trimester
The fetal brain takes control of chest muscle compression and diaphragm movement, starting practice breaths controlled by the brain stem. The fetus continues to experiment with movements like kicking and stretching, guided by the cerebellum.
Weeks 16 and 20, the baby becomes large enough for the mother to feel these movements, marking the development of the full range of specific fetal movements.
week 28: Brainwaves occur during sleep, controlled by the hypothalamus. -
All six layers of the cortex will have formed
About 25 weeks after conception, all six layers of the cortex will have formed from cell migration.
* cells move in an inside-out direction, beginning in the ventricular zone and migrating through the intermediate zone. Cells eventually reach their final destination on the outside of the developing brain. -
Period: to
Third Trimester
rapid neuronal development and growth in brain, tripling in size from 3 ounces to nearly 11 ounces at birth. The cerebrum starts forming grooves and ridges, dividing into the left and right brain. The cerebellum experiences the fastest growth during this period = increased motor control = more movement, wiggling fingers and toes, stretching, and kicking. the fetal sensory system shows integration and functionality during this period. -
Major structural changes
Around week 28 the cortex surface area will expand exponentially and form wrinkles and ridges -
Fills with Gyri and Sulci
from week 28-40, the brain will fill with Gyri and Sulci cerebral folds and wrinkles that will create a vast neural network. -
Birth: 100 Billion Neurons
Babies are born with 100 billion neurons connected by 50 trillion synapses. While this is all the neurons the human brain will have, it is only 25% of the adult size.
the neurons are connected by about 50 trillion neural connections compared to the 500 trillion synapses an adult brain has. -
Period: to
First year of life
- peak of production of synapses
- pruning happens to reduce population - dependent on experience and is the basis of learning in the early stages of life.
- Structures of the brain reach their peak of synapse production at different points
- The visual cortex peaks between the 4th and 8th month
- The prefrontal cortex reaches its peak around 15th month.
- The timing of peak synapse production affects the timing of the plasticity of regions a later peak = longer plasticity duration
-
Period: to
Sensorimotor Stage
Sensorimotor Stage Explained .30-1:53
A child's experiences affect their brain development.
- The plasticity of the brain underlies much of the learning that occurs during this period
- infants are sensitive to most language sounds in the first half-year of life but during the second half they begin to specialize in their native tongue at the expense of the broad sensitivity to nonnative language sounds -
Period: to
Year 2 of life
- The experiences a child has during these first years of life heavily influence the development of the brain, whether positive or negative.
- There is a major increase in the rate of myelination, which helps the brain perform more complex tasks. Higher-order cognitive abilities like self-awareness are developing: an infant is now more aware of their own emotions and intentions.
-
