Here's an extract from a new book we are currently developing on How Children Think. The book will be available in a few months from now, if all goes well.
Understanding an Infant (0-18months)
Physical and Motor Development
Many changes occur in the first 18months of a baby’s life. When babies are first born they have very basic motor abilities. They have a range of inborn reflex responses that occur involuntarily in response to specific stimuli. These reflexes are primarily to ensure the baby’s adaptation and survival in their new world. Basic reflexes include breathing, sucking, blinking and swallowing. These reflexes will stay with the child for life, but become partly, or entirely voluntary responses. Babies are also born with a range of other reflexes that weaken and disappear over a few months. for example the rooting reflex, where the baby turns their head in the direction of touch to the cheek (in order to find breast or bottle to feed), and the grasping reflex, where the child will curl their fingers around objects placed in their palms.
Along with these reflexes, infants start developing motor skills (voluntary movements). Development usually occurs from top down – motor skills develop first in the head, then the torso and arms, then the legs – and from proximal to distal – motor skills in body parts closer to the centre (such as entire arm and leg) develop before motor skills in body parts further from the centre (such as wrists and fingers).
All babies are different in the exact age that they reach specific milestones, but the order of developmental progression is generally the same. Once the infant has mastered one skill, they will build on it and progress to the next skill, and so on. Below shows the general timeline for infants motor development.
Age Skill mastered
• 4 weeks – 2months Lift the head when lying on the stomach
• 2 – 6months Roll over
• 3 - 6 months Reaching and grabbing
• 4 – 6 months Supported sitting
• 6 – 8 months Sitting up without support
• 6 – 9 months Pulling up to stand with support
• 6 – 10 months Crawling
• 7 – 10 months Walking with assistance
• 10 – 13 months Standing alone
• 11 – 16 months Walking alone
During infancy, the brain is developing at a rapid rate. Within the brain there are millions of neurons, connected to each other by synapses. All the neurons are created prior to birth, but the synapses, or pathways between the neurons are being constantly created and re-created. The pathways create structure within the brain, so when the baby has an experience, when the same experience appears again, their cognition of the experience occurs faster because the pathway is already in place. These pathways get strengthened, or weakened, depending on how often the event is experienced, and begin to form patterns of thinking that can continue into adulthood. At this stage in development, an infant’s primary caregiver has a vital effect on healthy development. Up until about age three, these synapses continue to form until the brain is dense with connections. This continues until around age eleven, when the brain eliminates pathways that are no longer used, making the remaining pathways more powerful - allowing for more effective and efficient mental processing.
Primary caregivers can have a profound effect on an infant’s cognitive development at this stage. Providing the infant with stimulating experiences (for example colourful toys, frequently being spoken to, interactive toys, interesting sounds and smells, novel environments and stimulus) increases the number of synapses that are formed, which can facilitate learning at a later stage. Infant’s that are not spoken to often, and have had limited experiences exploring their environment can end up with a permanent intellectual disadvantage, despite having a normal genetic make-up.
From a very young age infants begin to develop recognition and memory abilities. Although they can not report their memories, in studies, psychologists measure infant’s heart rates to gauge their response to specific stimuli. Novel stimuli will cause curiosity and a decreased heart rate, whereas familiar stimuli will either cause no change, or an increased heart rate. Studies have shown infants will display recognition for an object, even after a period of time, suggesting a display of memory function.