What is the difference between sensation and perception?

Sensation is the process by which sensory receptors detect physical energy from the environment and convert it into neural signals, a process called transduction. Perception is the brain's interpretation and organization of those sensory signals into meaningful experiences. Sensation is bottom-up processing, driven by raw sensory data. Perception involves top-down processing, where expectations, knowledge, and context shape interpretation. For example, sensation detects sound waves hitting the eardrum, while perception interprets those sounds as a familiar song.