The human brain – the most complex thing in the universe. And this brain is built from scratch in 9 months. Just think – the brain you are using to read this article was once a cell!
Brain development is one of the most fascinating stories of pregnancy. Today I will tell you how this process begins, when it peaks, and some facts that will amaze you.
Week 3-4 – The very first step
Brain development starts very early – hello in the first weeks of pregnancy!
By the end of week 3, a structure called the neural tube is forming. This is a small tube that will eventually become the brain and spinal cord – the entire central nervous system.
This is such an important structure that doctors recommend taking folic acid at this time – because it helps the neural tube develop healthily.
Week 5-6 — Brainstorming the three parts of the brain
By week 5, the neural tube appears to be dividing into ten segments – these three segments will go on to form the major parts of the brain:
Forehead — This will go on to become the brain that thinks, understands, and acts consciously.
Midbrain — This will coordinate hearing and vision.
Hindbrain — This will control balance, movement, and basic life functions (such as breathing)
This is all happening so fast that at that point the embryo surf is the size of a raspberry!
Week 7 — Brain cells are destroyed (from Achi Tara!)
This is where things get really crazy.
At week 7, a baby’s brain is growing about 100 new brain cells every minute!
Think about it — 100 new cells in 1 minute. 6,000 in 1 hour. Over 1.4 million in a day!
This rate of growth is so rapid that we never experience it again in our lives. Our adult brains never grow at this rate.
Week 8-9 — Brain Wrinkles Begin
You may have noticed that the human brain has wrinkles — this is where the work begins!
These wrinkles (called “gyri” and “sulci”) are formed to smooth out the surface area of the brain — the more wrinkles, the more space for neurons, the better processing power!
Weeks 12-16 — Different parts of the brain begin to function
Is the stage at which a baby’s brain develops enough to control basic functions:
Movement control — so the baby starts to move around when he is awake.
Reflexes — sucking reflexes, grasping reflexes all begin
Basic sensory processing — begins to process touch
Weeks 18-24 — Making the connection between listening and seeing
This stage is very exciting because now the brain begins to connect with the senses.
Week 18 — The auditory cortex (hearing cortex) develops so that it can process the vibrations of the baby’s voice
Week 24 — The visual cortex develops, although the eyes are still closed
This is when baby really starts to experience his “world” — not only is he not just growing, but he is also processing what is happening around him!
Week 27-28 — Brain waves detect what is happening!
This is a very special milestone. By weeks 27-28, the baby’s brain is forming enough to be detected by a machine – just like a newborn baby!
And at this time, REM sleep is also noisy – meaning the baby starts dreaming!
This stage proves that the baby’s brain is no longer just “developing” – it is actively “working”, like a small computer that has been switched on.
Weeks 32-36 — Brain folds become a complex structure
Brain development accelerates in the third trimester, during which the baby’s brain doubles in size!
This is when the folds (wrinkles) begin to take their final form — which will continue to develop after birth.
The brain continues to develop even after birth.
It’s important to understand this – brain development doesn’t stop in pregnancy!
When a baby is born, their brain is only about 25% of its adult size! The rest of the development occurs in the first 2-3 years — so this stage is so important for children to have proper nutrition and stimulation.
Do the mother’s activities affect brain development?
Of course! This is a very important topic.
Achi activities that help brain development:
✅ Balanced diet — Especially folic acid, omega-3 fatty acids, and iron ✅ Talking and singing — Stimulates the baby’s auditory cortex ✅ Stressful work — High stress hormones negatively affect brain development. ✅ Adequate rest — The body gets time to heal and grow.
You should avoid these things:
❌ Smoking or alcohol – these can seriously affect brain development ❌ Too much stress ❌ Poor nutrition
Mind-blowing facts about brain development
Fact 1: A newborn baby’s brain contains about 100 billion neurons — the same number as an adult brain!
Fact 2: During pregnancy, the brain forms millions of new connections every second.
Fact 3: A baby’s brain grows so quickly that by the time it is born, it makes up 10% of the body’s weight—in adults, it’s about 2%!
Fact 4: While still in the womb, babies begin to “learn” their mother’s voice, taste, and emotions – all of which is recorded in the brain.
Quick Timeline — Brain Development
| Week. | What happens? |
|---|---|
| Week 3-4 | The neural tube forms. |
| Week 5-6 | Make noise with three parts of the brain. |
| Week 7 | 100 brain cells per minute! |
| Week 8-9 | Make your brain wrinkled. |
| Week 12-16 | Controls basic functions |
| Week 18-24 | It is connected to consciousness. |
| Week 27-28 | Brain waves occur, and dreams occur. |
| Week 32-36 | The brain doubles in size. |
| Birth | Surf 25% complete – rest in progress |
Frequently Asked Questions
Q: When does a baby’s brain start to develop? The neural tube forms in week 3 – this is the law of brain development.
Q: Does listening to music during pregnancy improve a baby’s brain? There is no direct evidence of a “smarter banana”, but music is calming and stimulates the auditory cortex – which is healthy.
Q: Does stress affect a baby’s brain? Chronic, long-term stress can have a slight effect. Occasional stress is normal and does not matter.
Q: Is a baby’s brain fully developed by the time it is born? About 25%! The rest of the development occurs in the first few weeks.
Q: Is folic acid essential for brain development? Absolutely! Folic acid plays a very important role in the healthy formation of the neural tube – that’s why doctors recommend taking it before pregnancy.
The last thing
The brain of a child is formed — this marriage is the most complex and amazing work of nature. In a few hours, from a simple tube, the most powerful “computer” in the world is formed — with emotions, memories, thoughts, and dreams.
Every time you talk to your child, recite a prayer, or just lovingly place your hand on his stomach – you directly contribute to the development of our brain. How powerful it is!
We believe in the beat of a small heart – science and love go together on an incredible journey. 🌸
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This article is for educational purposes only. Please consult your doctor for any medical concerns.
