When sound waves produced by an animal excite receptors in 2-year-old Ben's ears, has occurred. When that sound is identified as being the "moo" of a cow, has occurred.

The correct answer is sensation; perception

The sensation is the ability to encode certain aspects of the physical and chemical energy that surrounds us, representing them as nerve impulses capable of being understood by neurons, that is, it is the reception of stimuli from the external environment captured by any of our five senses: visual, auditory, tactile, olfactory and taste. The sensation allows these senses to exist.

Perception is the ability to interpret this sensation, associating sensory information to our memory and cognition, in order to form concepts about the world and about ourselves and guide our behavior. For example, a sound is picked up by our auditory sensation, but identifying whether that sound is a human voice, a horn or a cracking noise is up to our auditory perception. Likewise, when I see an object captured by my visual sensation, visual perception will interpret and associate that image with a concept, where I may be seeing a sofa, a radio or even a pet.