It is widely known that the most critical time for human brain development occurs within the first few months of life.  One question that is constantly asked is "Do early influences either good or bad effect the brain's development process?".  Scientists have shown results proving that the following factors will affect the way the child's mind develops:

Recently, there have been more studies concentrating on the way that the brain uses cortisol.  Cortisol, along with other hormones are important in the way that the brain handles extreme situations.  The production of these hormones increases during these situations, helping to create extra energy the body may need.  They also suppress the body's immune system response for a short period of time, which helps heighten our attention span. 

Research has shown that people who suffer from depression produce an excess of cortisol that stays in their body for an extended amount of time, which may cause a negative impact on the person's health.  This long excess of cortisol has been known to shrink parts of the brain that help organize our memory.

In studies conducted with baby rats, scientists show that by removing the babies from their mothers for fifteen minutes, this causes the mother's maternal instinct of licking and grooming the baby upon return to occur every time the baby was placed back with the mother.  This grooming instinct from the mother lead to somehow altering the brain's chemistry in the baby that had a positive effect.  It would make the baby act better in a stressful situation.  This study concluded that even though the babies could handle the stressful situation properly, their reaction to the situation was not extreme.  This study also shows that the babies who were handled by humans causing the mother to groom the rats more often, had the same reaction as the babies whose mother cleaned them excessively.

When the baby rats were taken from their mother's side for three hours a day, upon their return the mother's instinct was to ignore the baby, at least for a short period of time.  This is in stark contrast to those babies who were only away from their mothers for fifteen minutes.  The rats that were removed from their mother for three hours exhibited a more noticeable and excessive stress response. The responses from this test appeared to last until the babies were full-grown. 

Although the results of the study are not very reassuring, research continues to see if the response from the babies who were away from their mother for three hours is a reversible response.  In one example, these neglected babies are placed in a cage with a foster mother rat, who grooms the baby like the mother did to the baby that was only gone fifteen minutes.  So far, the theory that the foster mother grooming the baby has proven to help reverse the effects of the birth mother ignoring the baby.  Other situations that helped reverse these effects include:

Research has shown another form of long-term change that is linked to the early stages of life, such as when the baby rat lived in a shoebox or a very small cage, with little or no source of stimulation.  In this study they found that the rats raised in the shoebox or small cage, had differences in the makeup of their brain from those rats who were brought up in an environment that stimulated their mind.  The rats that were brought up with a stimulated mind, had a more dense network of nerve cells and a thicker cerebral cortex.

Recently, a study was conducted on infant monkeys, who were raised by mothers that had problems in obtaining food for their babies.  It was found that the babies whose mothers were having trouble obtaining food, produced extremely high levels of cortiocotropin releasing factor (CRF).  The CRF was found in their cerebrospinal fluid.  This same pattern occurs quite often in humans who suffer from depression or post traumatic stress disorder.  When the mothers could not find food for their babies, the mother's behavior changed and became inconsistent with what is considered normal and often led to neglect of the babies.  The babies from these mothers became abnormally anxious in a stressful situation or when placed in a strange environment.  The babies were also more anti-social as adults than normal monkeys.

Although there has been  a lot of research in this field, researchers say it is still too early to draw conclusions about the extent of how our early lives effect our adult minds.  They hope that future research and interactive studies will help determine just how much early situations help to develop our adult brain.


Sources:
http://www.cogsci.ucsd.edu
http://www.nimh.nih.gov
http://www.unt.edu
http://www.mind.org.uk
http://www.uoregon.edu