A chemical brain receptor known as N-methyl-D-aspartate (NMDA) and which is associated with learning and memory is perceived to play a key role in respiratory system of the fetus. This brain receptor was isolated using high-powered binocular biological microscopes.

With this new development, pregnant women are advised to avoid unnecessary exposure to such substances as alcohol. PCP (angel dust) and some anesthetics and analgesics like ketamine.  The study links a possible connection between abnormal receptor (identified using high powered binocular biological microscopes) and problems in newborns, although further studies using high-powered binocular biological microscopes are needed to confirm this.

A surprise discovery, as described in the original article, showed that lack of the said receptors led to high amounts of long term synaptic depression (LTD), an activity connected with learning and memory, yet an increased LTD in the brain stem is not at all connected with high-level functions.

The NMDA is the key to chemical communication between two nerve cells, and if such activity is repeated between many cells, it provides data on how much signals are propagated in the brain.

If the effectiveness of the transmission is changed or modified over time, this then is believed to be the basis for learning and memory.  If modification last longer, so is the memory.

According to the original article, mice were subjected to decreased sub unit of NMDA receptor to see how knocking out the receptor affects the hypo campus on cellular level and what are its effect on memory and learning.  Unexpectedly the animals died after birth.  That problem was later solved by applying the knocking out on a specific brain area, but reasons for their death was yet unexplored.  Eventually the answers seem to be that the lack of NMDA receptors during the pre-natal development, led to fatal respiratory problems.  Although, the newborn mice treated with drugs that block NMDA receptor encountered no such problems.

All in all the indication is that pre-natal development of specific region in the brain controlling vital development of specific region in the brain controlling vital functions is dependent on NMDA receptor activity and lack of it can affect respirators after birth.