Ch. 3 Sensation and Perception
Sensation- Process of receiving stimulus energies from the external environment
* This is a biological process
* Sensory receptors- openings through which the brain and nervous system experience the world
* Specialized cells that detect stimulus information and transmit it to sensory (afferent) nerves and brain.
Take place in different forms of stimulation
* Photoreception- Detection of light
* Perceived as sight
* Mechanoreception- Detection of pressure, vibration, and movement
* Perceived as touch, hearing and equilibrium
* Chemoreception- Detection of chemical stimuli
* Perceived as smell and taste
Perception- Process of organizing and interpreting sensory information
This is a psychological process
Stimulus Energy (Light, sound, smell, etc)- Sensory Receptors (ears, eyes, nose etc)
[- -----------------sensation-------------------------
Neural impulses Brain (visual, auditory, olfactory areas)
-------------- Perception]---
Absolute Threshold- The lowest level of stimulation that a person can consciously detect 50% of the time the stimulation is present. Minimum amount of detectable stimulus energy needed to reliably trigger a sensory receptor
Bottom Up Processing-
* Stimulation works its way from the environment up to the level of the brain
* Stimulation (Light)Sensory receptorsBrain
* The Brain takes its first stab at understanding the information
Top-Down Processing- kicks in once bottom-up has taken place
* Based on cognitive processing at higher levels of the brain
* Brain uses previous experiences and memories to organize the information into something it understands
* By doing this, simplifies the information. Rather than processing it as a large amount of sensory information, the brain can now apply a single label ex: “This is a car”
Gestalt Principles- Set of principles in psychology to account for the observation that humans...