The brain development section at the top shows a brain scan of a newborn. The attached text reads, an infant’s brain grows rapidly during the 1st year of life, more than doubling in size.
At 1 month, there is an illustration showing neural formation - there are few neurons, and they are spaced apart. The attached text reads, at birth, an infant’s brain has roughly the same number of neurons as that of an adult, Kolb & Gibb, 2011.
At 9 months, there is an illustration of the neural formation. At this point, there are more neurons, and they have begun to join and connect.
At 12 months, there is a brain scan showing a larger and more complex brain than a newborn. The attached text reads, there is dramatic growth in axon length and synapses, which make up gray matter. Also, myelin is increasing significantly around axons, improving the efficiency of neural communication. The myelinated white matter is shown in these scans, Shi et al., 2011.
At 15 months, there is an illustration of neural formation - there are more neurons, and they are more connected.
The attached text reads, But as the infant matures, the dendritic connections grow increasingly complex, eventually becoming refined based on experience.
At 24 months, there is a brain scan and an illustration of the neural formation. Both show more complex and fully developed functions. The motor and sensory development timelines are shown below.
At 0 months, there are two sensory milestones; Babies can discriminate the smell of their mothers’ milk, and prefer sweet tastes. At 1 month, there is one sensory milestone, which reads babies search with their eyes for sound. In between two to four months, babies can roll over. At four months, there is a sensory milestone where babies have well-established close vision.
In between 4 and a half to 8 months, babies can sit without support. In between 4 and a half to 10 months, babies can stand while holding on. In between 9 to 14 months, babies can pincer grasp. In between 10 to 14 months, babies can stand alone easily. In between 11 and 14 and half months, babies can walk alone easily. In between 12 and 20 months, babies can build a tower of two cubes. In between 14 and 22 months, babies can walk up steps. Text attached to the chart reads as follows; Along with continued brain development over the first 2 years of life, we see advancement in demonstrated capabilities, known as the motor milestones. The general sequence and timing of these increasingly complex movements is fairly universal, Frankenburg, 1992. More subtly, but along the same timeline, babies’ abilities to discriminate among things in their sensory world also become progressively more sophisticated, Bayley, 1993; Feigelman, 2011.