The Baby’s Brain, 2015 Updates

Being raised in poverty has a direct relationship to IQ and child development. When parents spoke to their children with an affectionate voice, spent time answering their questions and hugged, kissed and praised them they tended to have higher IQs, doing better on language tasks and memory tasks. Many years later, children in this population of studies had MRIs. It showed a strong link between how the brain developed and the impact of early childhood experiences. The baby’s brain is an incredible learning machine that is largely dependent on its environment.

New technology lets us see how the brain learns from birth to age 5. At birth the brain has nearly a hundred billion neurons, as many as in adulthood. As sensory input occurs, neurons get wired to other neurons, resulting in some hundred trillion connections by age 3. Different stimuli create different networks, circuits created by repeated activation. The brain goes through cycles of growth and streamlining, experience playing a key role. A newborn can discriminate auditory repetition and where it takes place in the stream of sound, a precursor of language. Language learning is part of the neural network that babies are born with, including grammatical rules. Understanding is phonologically based, or how the words sound. The flowering of language comes as a result of new connections between neurons so that speech is processed on multiple levels: sound, meaning and syntax. The physical structure of the brain is not enough, however, because input is needed in order to develop.

Children in well-off families heard an average of 2,153 words an hour spoken to them, while children whose families were on welfare heard an average of 626 words. Poorer homes used shorter sentences, whereas higher income families encouraged imagination and memory and used longer sentences. Language delivered by TV does not do the job. Children exposed to language through human interactions were better able to discriminate sounds, while those exposed to video or audio recordings did not. Social experience is the portal to linguistic, cognitive and emotional development. More play within the home is encouraged because play leads to learning. (The First Year, National Geographic Magazine, Yudhijt Bhattacharjee, 10/15).

Current research has also provided crucial information about how babies develop a sense of their physical selves and early social relationships. Body maps in the brain are an important part of how we build up an implicit sense of ourselves by sensing how our body moves and feels. These maps may facilitate connections we build with other people, even in the early months of life. Body maps in the infant brain are activated by seeing other people carry out actions with different parts of the body. This imitation is caused by mirror neurons. Language is based on imitation, mapping the behaviors seen in others. One of the big challenges in psychology is to make meaningful connections across brain, behavior, cognition and the social processes. Body maps on the surface of the brain easily pick up and analyze signals in order to better integrate the information received from the various inputs. (Body Maps in the Infant Brain, Trends in Cognitive Sciences, Marshall & Meltzoff, 2015)