Sensation and Perception
We bring information about the world around us through a chain of events known as sensory information processing. The first part of this process is sensation, the activation of sensory receptors by physical stimuli and the transmission of neural signals to the brain.
The second part is perception, the final mental representation of the original stimuli as organized by the brain. This chain of events, from sensation to perception, is a single continuous process.
Sensations can vary in following ways: quality, timing and the information they carry about location. Adaptation allows us to react quickly to any change of stimulus once our senses are exposed to a constant, unchanging level of stimulation.
The sensory systems include:
- Sight – Light waves are the stimulus for vision.
- Hearing – Sounds waves are the stimulus for hearing.
- The skin senses: Touch – receptors in the skin are sensitive to three different kind of skin sensations: temperature, pressure and pain.
- Smell – the sense is extremely sensitive.
- Taste – receptors on the tongue can experience only sweet, sour, salty and bitter.
- The vestibular sense – contributes to balance.
- The kinesthetic sense – the sense of body movement and position.
Perception is an active process, which means that we must act in order to perceive. We sense stimuli, but we perceive objects and events. Perception is usually effortless and integrates the information picked up by the senses.
The function of perception is it tells you where an object is in relation to yourself. Locating an object begins by focusing attention on it. Depth perception can determine an object’s absolute or relative distance. Size is also an effective cue to depth, and perspective provides a wealth of information about distance. Differences in sound intensity and arrival time also help us locate objects.
By Meeka O Brien