Sensation how sense organs respond to external stimuli and transmit the responses to the brain. Perception - the processing, organization and interpretation of sensory signals that result in an internal representation of the stimulus and a conscious experience of the world. Stimuli must be coded to be understood by the brain. The way our sensory organs translate a stimulus"s physical properties into neural impulses is called sensory coding. Transduction a process by which sensory receptors produce neural impulses when they receive physical or chemical stimulation. Most sensory information goes to the thalamus which sends information to the cortex where the incoming neural impulses are interpreted as sight, smell, sound, touch or taste. Quantitative factors such intensity, brightness and loudness are indexed by neural firing frequency. Qualitative coding, useful for things like colour and taste, are facilitated by certain types of receptors being able to code for certain types of stimuli.