When one axon connects to another this connection is called a synapse. These connnctions can be modulated by chemical feedback loops allowing more or less activity and connectivity. Our whole body is controlled by feedback loops. The ones in the brain are still being discovered:-http://medicalxpress.com/news/2013-06-scientists-brain-cells-long-term-memories.html-The brain's functions are not fixed, but very plastic. Use it or lose it!