WE ARE OUR BRAINS - CHAPTER 2
THREATS TO THE FOETAL BRAIN IN THE "SAFETY OF THE WOMB"
Our brains develop with incredible rapidity before birth and in the years immediately after. The brain cells grow at different rates and are extremely susceptible to different factors.
Growth is determined by 1)our genetic factors and 2)the activity of the neural cells which in itself depends on:
Availability of nutrients, chemical messengers, growth regulators, hormones.
Lack of nourishment: from hunger, placenta malfunctioning, excessive vomiting by the mother, dieting for weight issues, Ramadan fasting. These all impair the child's mental capacity, increase the risk for schizophrenia, depression and antisocial behaviour.
Iodine deficiency impairs thyroid hormone production: impaired brain and inner ear development.
Heavy metals cause brain disabilities.
DDT, PCBs, dioxins are called environmental disrupters because they disrupt hormonal regulation of sexual differentiation even when there is no chromosomal cause - gender identity and sexual orientation is affected.
Most problems are only small, children seem to be healthy at birth, but then manifest issues later. Smoking women can cause learning difficulties, behavioural and reproductive problems for example.
ALCOHOL
In early development, brain cells are created around the brain cavities. They migrate to the cerebral rotten, where they ripen and sprout tissue to establish contact with other brain cells. This migration can be so severely disrupted by alcohol that cells can end up migrating outside the brain. Alcohol also permanently activates the stress axis, increasing the risk of depression and phobia.
SMOKING
Is the most common cause of neonatal death. Doubles the risk of SIDS (sudden infant death syndrome). Increased risk for premature brith, low birth rate, impaired brain development, disturbed sleep patters, poor school performance, obesity, thyroid function, ADHD, aggressive behaviour, impulsiveness, speech defects, attention problems, impaired testes development.
SLEEP
REM sleep: rats with less REM sleep during comparable-to-human-foetal-development-stages, they had less REM sleep and were more fearful in adulthood. The sex drive in males diminished, they were hyperactive.
Heterotopias: are a group of cells that end up in the wrong part of the brain during their migration to the cerebral cortex.
The brain overproduces cells and synapses. When connections are promoted, they obtain growth substances that make them more active, enabling them to make more and better connections. The cells that fail to do so, die of. Extreme signals form the outside lead to the foetal brain being permanently modified to prepare the child for the outside world.
Nazi occupants of Netherlands during WWII lead to a famine. They babies born then were not only underweight, but more likely to become antisocial and obese later in life: to prefer fatty foods, exercise less. More likely to have HPB, schizophrenia, depression. Their brain was programmed to retain every calorie. Being antisocial they defend their own interests, giving an advantage in times of scarcity. But if they are born into normal surroundings these qualities are not good.
When a mother is stressed, the brain of the female foetus becomes more male and vice versa: a more competitive girl is more likely to survive and so is a less aggressive male.
Longevity is only a very recent accomplishment, it made sense for the foetus to be adapted to the immediate environment it came to.
PAIN TRANSMISSION
1) nerve fibres in the skin
2) along the spinal chord
3) the centre of the brain: the primary sensory cortex, the brain becomes aware of the brain; the thalamus: the cingulate cortex, the brain's alarm centre causes emotional and autonomic responses.
Because these are two separate centres, you can have responses to pain: heart rate, contorted face, movement, without actual awareness of it.
By week 7 of foetal development, the sensory nerves are there, so there will be a physical response to a needle for example, but this doesn't mean it can actually feel pain.
The cortex needs to be mature, and this happens around week 29 or 30.
General anaesthesia is a risk for the mother. If a procedure need to be done on the foetus before week 25-26, it would probably be better not to use anaesthesia because of the risks in brain development.
Body Integrity Identity Disorder: where someone early on is convinced that a part of their body doesn't belong to them and they become desperate to get rid of it, even though it can be fully functioning and healthy. They can get jealous of amputees or paralysed people. They will pretend not to have that limb. They will try to get a doctor to remove it. They can even damage the limb to the point that it has to be removed. They have very precise ideas where from they want the amputation. Scans show their frontal and parietal cortices respond differently to the touch of their two limbs.
This shows a similarity with transsexuality, and in fact 19% of BIID patients have a gender identity problem, and 38% are homosexual or bisexual.