Why can't humans remember their time in the womb or as little children?

The part of the brain that processes and stores long term memories hasn't developed yet. It doesn't develop until you're a few years old, hence why most people's earliest memory is from when they're at least 3 :)

> in the womb
I remember one author came up with the idea that having one's head smashed, squashed, and stretched during childbirth also caused a baby to forget everything from before that time.
Sorry, I can't cite a source on that. Nor did the author elaborate on Caesarean section versus natural childbirth.

> or as little children
Another author came up with the idea that we have different ways of "indexing" our memories before we have a big enough vocabulary. At some point we stop using the earlier indexing system, and the memories are less retrievable -- although -- still there.

actually, I have a few fleeting memories of my time in the womb, and many many memories as a child (even 'before I could talk'). But I think by and large, the human brain doesn't have the structure to remember at that early state of development

You ask a good question about human biology. Yes, a baby does have memories. It learns sounds, words, and make logical associations. During the first three years of life the brain produces neural connections at a feverish pace. It is called synaptogenesis, and by age 3 the brain has about 5X the neural connections as an adult. Then, largely through the learning processes, the brain undergoes a process of neural pruning where some connections are reinforced while others are removed.

Then between the ages of 5 and 7 the brain undergoes another process known as childhood amnesia, where memories that are not actively reinforced are removed. Yes, this is part of the neural pruning process. The brain determines that many of these "unreinforced" neural connections are unimportant. However only people who have been recalling these memories since early childhood will have these early memories retained through reinforcement.

The part of the brain that processes and stores long term memories hasn't developed yet. It doesn't develop until you're a few years old, which is why most people's earliest memories are from when they're around 3

Neurons only start forming at 10 weeks after birth. When babies reach 1 year old, something special happens
----- Synaptic pruning: synapses begin to disappear gradually. Synapses that are active are preserved, but those that aren’t active are eliminated. The brain pattern changes to make space for new ones, consequently, the neurons the baby didn't require for survival are eliminated. It's a sort of automatic brain filter.



Source: I read a 500 pg textbook on child development during the summer,

memory lost. People tend to forget things from time to time. Simply because we aren't computers. Computers can store anything. People are constantly developing, changing in body and size, and even thoughts. Therefore, it is natural that some pieces are still missing, as we cannot remember everything. Even computers have a quota limit to what you can put in. So this theory proves similarly that a being cannot have everything.

The part of the brain that is responsible for remembering and recollection is not fully developed yet; as a result, an infant cannot recall their time in the womb

This is because during the age of being born - 3 years your hippocampus, which is where all your memories are stored, can't handle remembering memories at this time because you're in the early stages of life. Once you turn 3 years of age your hippocampus is now able to remember memories.

It is widely accepted that babies in the womb do learn and remember some things. For instance, the cadence of speech, the rhythems and song of the words are remembered, this gives the child a comforting start when born as it will remember the sound of the mother's voice. The human baby is born so undeveloped because the mother and the placenta are unable to provide nutrents and oxygen for a larger more developed child.