Sensory development

By Dr. Lin Day, Baby Sensory

The newborn’s brain is only a quarter of adult size, but by the end of the first year, it will have doubled in volume. This growth is largely due to the trillions of neural connections, which allow messages to be passed from one area of the brain to another. These connections are the direct result of events and experiences encountered from birth.

Babies need stimulating experiences. An environment full of interesting sounds, sights, smells, tastes and textures builds and strengthens connections between brain cells, which ultimately shapes behaviour, memory, emotions, intelligence and other essential mental skills.


The neurosensory part of the auditory system becomes functional at about 25 weeks gestation. This is the time when the ear and the temporal lobe of the brain tune into specific frequencies and intensities such as the mother’s voice and the rhythmic sound of her heart. These same sounds provide comfort and reassurance to the newborn baby.

Hearing continues to develop up to 6 months after the birth. Sound experiences, verbal interactions, rhymes, singing and stories build important neural connections for speech and language skills and they contribute to all-round development of the brain.


At birth, the eye and brain areas responsible for vision are immature. Although babies can see colours, they may appear blurred. However, by two months of age, colours become distinct and the baby can track the movement of an object if it is not too far away. By 6 months, significant advances have been made in the vision centre of the brain. Colours can be seen clearly, and both eyes can track and focus accurately on a moving object.

At 8 months, babies can see with much greater accuracy. Even so, it takes another four years for vision to reach the full adult level, which is why continual visual stimulation is so important.


At birth, the sense of smell is fully mature and babies have the capacity to distinguish thousands of different smells. Most babies are responsive to smells that they encounter daily such as breast milk, the mother’s perfume or a familiar blanket. Such smells are associated with comfort and security.

Smells are received by receptors at the top of the nasal passage, but they are processed and interpreted by the temporal lobe in the brain. Signals also pass through the limbic system, which is heavily involved with memory, mood, behaviour and basic thought processes. Stimulating babies with different smells develops brain connections and helps them to learn about the world. 


The sense of smell is closely associated with the sense of taste. Taste buds on the tongue can distinguish sweet, sour, bitter and salt, but all other tastes are detected by smell receptors in the nose.

When an object is brought to the mouth, the lips and tongue provide a very accurate image of texture, size, weight, shape and temperature. Mouthing is often accompanied by vocalisations, which play an important role in speech and intellectual development. Mouthing also develops skilful jaw and tongue movements in readiness for solid foods.


Babies need to touch interesting objects and textured materials in order to develop and strengthen connections between the brain cells. Whenever an object is grasped or explored with the fingertips, millions of sensory receptors send messages to the brain, which then processes, analyses and stores the information. Touch also stimulates parts of the brain that govern action, coordination and thinking.

Parents can also nurture the sense of touch by giving babies plenty of loving attention and comfort. Close physical contact and sensitive, responsive care builds emotional brain connections that lead to happy, healthy relationships. Babies also gain weight faster, develop stronger immune systems, crawl and walk sooner, sleep more soundly and cry less than babies deprived of close physical contact.

Note: The views and advice expressed on this blog post are those of the author and are not representative of the Pregnancy Babies & Children's Expo.

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