is the process by which foreign DNA is introduced into a cell by a virus or viral vector. An example is the viral transfer of DNA from one bacterium to another. Psychology Definition. Ok, so how does our eye turn the light into neural impulses so that our brain can understand. Most of the process occurs on the back of the eye called the retina. The retina is the most important part of our eye. Stimulation of this area leads to conscious awareness of the sound, but the transduction from mechanical vibrations to neural activity occurs in the inner ear.