The fear of the train and dark is an expression of the immature development of his prefrontal cortex.
This is the part of the human brain that is known to be in front of the frontal lobe. It is responsible for the complex behaviors in humans.
This part of the brain is the area that is known to be responsible for the development of personality.
Read more on the prefrontal cortex here:
https://brainly.com/question/24171355
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