Sensation and Perception

Sensation involves detecting physical stimuli from the environment via sensory organs and translating this information into neural signals that can be processed by the brain.
Perception is the next step after sensation, it involves the interpretation of sensory information, enabling us to understand and interact with our surroundings.
Five traditional senses; sight, hearing, touch, taste, and smell, are widely recognised, each associated with specific sensory structures.
The process of sensation begins with sensory receptors that respond to stimulus energy from our environment. These receptors translate this energy into nerve impulses.
The different types of sensory receptors include photoreceptors (light), mechanoreceptors (pressure), thermoreceptors (temperature), nociceptors (pain), and chemoreceptors (chemicals).
Transduction is the process where the body converts stimulus energy into electrical potentials ready for transportation to the brain.
Perception follows sensation. The brain uses what it already knows and anticipates, and applies it to incoming sensory data to make sense of the world.
Sensation and perception are part of the ‘bottom-up’ and ‘top-down’ processing respectively. Bottom-up processing starts with the sensory input and ends with how our brains interpret this information. Top-down processing involves our previous knowledge and expectations that influence our perception.
The theory of constructivist perception says that our brain uses past experiences to interpret sensory information and make sense of what we perceive.
Selective attention is the ability to focus on a specific aspect of experience while ignoring others. It’s crucial for processing and perception.
Factors influencing perception include context, culture, motivation and emotion.
Perceptual constancies (size, shape, colour, brightness) allow us to perceive an object as stable and unchanging despite changes in sensations.
Depth perception is the visual ability to perceive the world in three dimensions, allowing for distance judgement.
Optical illusions and perceptual set are examples of how perception can differ from physical reality.