Why N2O induces laughing gas?

In brain stem there is an area called reticules formation (a network of neurons and nerve fibers) - it keeps the controls on all the sensory inputs for the brain and it acts as a gate and a filter. Alcohol and N2O loosen the gate, so that any input get into the emotional part of the brain with out any regulatory mechanism. The filter mechanism doesn't work. People start laughing. My friend Dr. Selvamoorthy uses Nitric Oxide (NO) for treating patients with high altitude pulmonary edema. With two atoms NO, it is doing a constructive work, when three atoms joins it is doing destructive function.