"Primary reflexes play a crucial role in aiding the baby during the birthing process and serve a vital function in the first few weeks of life. Therefore, immediately after birth, the child is examined for the presence of all primary reflexes. Poorly developed primary reflexes could potentially suggest inadequate brain development.
The brain of a newborn weighs around 400 grams and is still immature, but it contains almost all the nerve cells required for the rest of their life. However, these cells are not yet adequately connected to each other. As a result, the baby initially relies on active primary reflexes that are located in the lower levels of the brain, which are already fully developed. The infant is bombarded with an overwhelming amount of stimuli that their brain cannot yet process well, and primary reflexes aid in responding adequately to these stimuli. Motor development in the child is also linked to the activity of primary reflexes. These reflexes stimulate the creation of connections in the brain, differentiation of nerve cells, and especially connections to higher brain centers, which subsequently take over overall control of the body. The movements produced by primary reflexes help to create a dense neural network that allows for the connection of different areas of the brain, which is crucial for future learning processes, communication skills, emotional and affective relationships, and motivation.
As the higher brain centers develop, primary reflexes gradually interfere and must be inhibited for the brain to develop in a neurologically correct manner. Motor development also stalls if primary reflexes persist longer than usual. Children may struggle to start crawling or climbing or may turn in the wrong direction (e.g., with a significant tilt of the head). Therefore, primary reflexes gradually weaken. The development of posture and movement functions essentially mirrors brain development. Improvement in movement control is an indicator of strengthened connections between the brain and body and within the brain itself.