Infant Brain and Sensorimotor Development

Brain development:

An illustration shows a scan of a small infant brain at zero months. Accompanying text reads, an infant’s brain grows rapidly during the first year of life, more than doubling in size.

An illustration shows a scan of a 24 month old infant’s brain. Text beside reads, here is dramatic growth in axon length and synapses. In addition, myelin is increasing significantly around axons, improving the efficiency of neural communication. Myelinated white matter is shown in theses scans.

Motor and Sensory Development:

Sensory milestone, 0 months: Babies prefer sweet tastes. Babies can discriminate smell of mother’s milk.

Sensory milestone, 1 month: Babies search with eyes for sound.

Sensory milestone, 4 months: Babies have well-established close vision.

2 to 5 months: Babies roll over.

4.5 to 8 months: Babies sit without support.

9 to 14 months: Babies pincer grasp.

10 to 14 months: Babies stand alone.

11 to 14.5 months: Babies walk alone easily.

12 to 20 months: Babies can build tower of two cubes.

14 to 22 months: Babies walk up steps.

Text reads, 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, assuming that basic health and nutrition needs are satisfied. More subtly, but along the same timeline, babies’ abilities to discriminate among things in their sensory world also become progressively more sophisticated.