Infant Brain Development Using Sensory Stimulation

Page content

At birth, an infant’s brain is one of the only organs that is not fully developed. It has recently been researched, that genetics no longer play the only role in infant brain development; a baby’s environment does as well. It is now known that sensory stimulation and neural pathway connections are major factors that lead to healthy brain function in babies.

Infant Brain Development

A newborn baby’s brain is only about one-quarter of that of their mom’s or dad’s. By the time they are five years of age, their brain size will be 90% of their parents' brain size. An infant’s brain develops at an amazing rate and research shows that the physical and emotional experiences they have in the first five years of their life directly reflect their learning ability and brain growth the rest of their life. Pretty crazy, right? Well, it is truly unbelievable, but now you are probably thinking, why does this happen and how? Sensory neurons and synapses are directly responsible for this dramatic and rapid brain growth.

The Role of Sensory Neurons

Billions of brain cells, or neurons, are formed throughout the first stages of fetal development and through birth. When an infant is born, the only part of the brain that is very developed, is the brain stem. This part of the brain controls functions such as; kicking, sleeping, rooting, crying and feeding. Right after birth, an infant’s brain begins making over a trillion neuron connections, or synapses which are used to transmit information based on various life experiences. Stimulation through the senses of touch, hearing, seeing, smelling, and tasting directly affect the sensory neurons and help in establishing these connections. According to research, an infant’s brain is producing 2-3 million synapses per second!

The more frequently the neuron connections are used, the more they retain information and the stronger they become. If some of the neural pathways are not used, they will end up dying out (this is called pruning). This is a necessary step in the brain development process for it prevents “overload” so to speak. Once these synapses gain strength and are noted by the brain that these are the pathways of important information, they become protected by a myelin sheath (a natural insulating material) that helps in sending messages to the brain even faster.

This process occurs mostly with the neurons and synapses that control a baby’s sensory areas such as the eyes, ears, nose, mouth, and skin. Many of these “new” connections help infants to reach important milestones such as color vision, develop a pincer grasp, or strive for parent attachment.

Importance of Positive Sensory Stimulation

According to Janet Doman, one of the authors of, How Smart Is Your Baby?: Develop and Nurture Your Newborn’s Full Potential, “a newborn baby is functionally blind, deaf and insensate.” She believes that it is up to the parents to use sensory stimulation to develop the sensory pathways that lead to proper brain development and function. Using positive sensory stimulation (through all five senses) in brief intervals will help these sensory pathways to become strong and therefore will achieve a sense of permanent learning.

As pathways develop, it will be easier for parents to understand the needs of their babies. By providing them with physical, emotional, and cognitive experiences, they will gain much more knowledge to use in the future. They need room for mobility, for hands-on exploration, and for communication in increased intervals and for longer periods of time. By exposing infants to these experiences, they will begin to become more comfortable with the world around them, which will encourage their own sensory stimulation and help to develop a connection with their families.

However, there are negative forms of stimulation that can lead to life-long developmental delays. Neglect, sress, trauma, and abuse are all negative stimuli that can have a tragic effect on brain growth. Studies show, that those infants or children that receive little to no attention and are not exposed to positive, purposeful stimuli by their parents, end up with brains 20 to 30 percent smaller then those who have had those “good” sensory experiences.

The development of an infant’s brain is essential to the life-long learning process and through proper sensory stimulation, your baby could one day turn into a genius right before your eyes!


Here are some references used for this article and some great resources for further reading as well.

This post is part of the series: Infant Brain Development and Sensory Stimulation

This series discusses the significance of sensory stimulation by parents on an infant’s brain development and overall health. You will find information on how an infant’s brain grows and what kind and specific make of toys are suggested to optimize infant learning.

  1. The Significance of Sensory Stimulation in Infant Brain Development
  2. Stimulating Your Baby’s Five Senses: The Most Effective Toys
  3. The Best Brand Infant Toys For Infant Growth