The human brain is “the most complicated object in the known universe”, according to psychiatrist and child trauma expert Dr Bruce D Perry.
The brain “has been caricatured as a rigid, genetically preset system that sometimes requires medication to adjust imbalances.” In fact, it is a dynamic system “shaped by evolution to be exquisitely sensitive to the people who surrounded it.”
We are born with a multi-purpose learning machine whose 86 billion cells are almost all present at birth, but whose wiring is in great part custom-built during the first three years of life based on the infinite sensory, emotional and cognitive stimuli we encounter.
Main parts of the brain
“While the body doesn’t reach its adult height and weight until adolescence, by age three the brain has reached 85% of its full adult size.”
- brainstem: Mediates our core regulatory functions such as body temperature, heart rate, breathing, blood pressure, the release of neurochemicals and hormones.
- diencephalon and limbic system: “handle emotional responses that guide our behavior, like fear, hatred, love and joy.”
- cortex: “regulates the most complex and highly human functions such as speech, abstract thinking, planning and deliberate decision making.”
“These regions ‘awaken’ sequentially during development.”
The various areas are connected in systems. “A foundational principle of brain development is that neural systems organize and become functional in a sequential manner.”
- One key set of neural systems is the stress-response system. It modulates the freeze-flight- fight response. It also plays a part in arousal, sleep, attention appetite, mood and impulse regulation.
- Relational and pleasure-mediating systems:
- epinephrine (adrenaline) and norepinephrine (noradrenaline)
- Dopamine: pleasure and motivation
- Endogenous opioids: endorphins, enkephalins, dynorphins
How the brain is built
From the bottom up and from the inside out, in a use-dependent way.
The importance of getting a good start “When things go right early on, they will tend to continue to go right and even to self-correct if there are minor problems. But if they go wrong at first, they will tend to continue to go wrong. (…) Parents don’t have to be perfect. But it’s important to know that young children are extraordinarily susceptible to the spiralling consequences of the choices we – and later they – make, for good and for ill.”
The importance of touch: “Physical affection is needed to spur some of the brain’s chemical activity. (…) At birth human touch is a novel and initially stressful stimulus. Loving touch has yet to be connected to pleasure. It is in the arms of a present, loving caregiver that the hours upon hours of touch become familiar and associated with safety and comfort.”
- Selection of articles on Neuroscience from Quanta Magazine
- Article – “The Power of Touch” (The New Yorker, March 2015)
- Video – “The most important lesson from 83,000 brain scans” ( TEDx, Daniel Amen, Oct 2013)