SENSATION & PERCEPTION Fall 2025

SESSION OUTLINE • Recap of Consciousness • What is sensation? • Absolute, subliminal, difference thresholds • What is perception? • The eye & vision • The ear & hearing • Perceptual processes • Gestalt theory • Extra sensory perception SENSATION • Sensation is the process of receiving, converting and transmitting information from the external and internal world to the brain • Sensation refers to the activation of receptors in various sensory organs • When sensory information is detected by a sensory receptor, sensation has occurred • Sensory receptors are specialized forms of neurons that receive and process sensory information from the environment • 5 sense organs: eyes (vision), nose (olfaction), tastebuds/tongue (gustation), skin (somatosensation; tactile), ears (auditory) • We also have sensory systems that provide information about balance (vestibular sense), body position & movement (proprioception, kinesthesia), pain (nociception) and temperature (thermoception) PERCEPTION • Perception is the process of selecting, organizing and interpreting raw sensory data into useful mental representations of the world that are meaningful • Perception refers to the way sensory information is organized, interpreted, and consciously experienced. • Perception involves both bottom-up and top-down processing. TRANSDUCTION • Transduction refers to the conversion from sensory stimulus energy to action potential • The sensory receptors (eye, ear, skin, nose, tongue) convert the stimulus into neural impulses which are sent to the brain • Stimulation  Transduction  Sensation  Perception TRANSDUCTION • Receptor cells in the inner ear convert sound waves/vibrations from a crying baby  into electrochemical signals • These signals are carried by neurons to the brain. Occipital lobes of the brain receive sensory information from • The ear and process it as the crying of a baby • The eye and process it as a but