When a brain cell or neuron is activated, meaning it receives an electrical impulse or action potential from a neighboring cell, then it in turn wants to transmit to the next cell in line the current information. In order to pass on the information, the neuron receives input at one end of the neuron, the dendrites, and at the other end, the axon will “communicate” with the dendrite of the next neuron, in order to “communicate.”
In between the cells is a space called “the synapse” and that is where the magic happens. The first cell is referred to as the pre-synaptic cell and the receiving cells is called the post-synaptic cell. The pre-synaptic cells docks vesicles of neurotransmitters, fuses them with the cell edge and then releases the neurotransmitters into the synapse. The post-synaptic cell has receptors that bind these neurotransmitters. The binding causes a conformational change and the receptor opens a channel in which charged ions enter the post-synaptic cell.
If enough receptors are active and enough charged sodium ions enter the cell then the cells charge changes causing an action potential along the cell’s axon. Repeated firing will cause activation and internalization of receptors inside the cell’s nucleus or brain of the brain cell. The nucleus of the neuron contains the DNA. Under these certain conditions, the DNA will unravel and allow a complex to read/transcribe its code making RNA. The code will then be translated to a protein which the cell will use like for making more receptors for the post-synaptic side to increase communication. Also a cell can make more “spines” using growth factors on post-synpatic side which will create more synapses for even more communication.
Changes in RNA and protein can be measured in response to behaviors. These changes can be quantified to see if a certain behavior can cause the brain to change or a certain treatment can cause the brain to change.