Chapter 4 Flashcards
What is sensation?
Stimulation of sense organs
Sensation is the initial stage of processing sensory information better known as bottom-up processing
Define stimulus in the context of sensation.
Physiological energy that serves as ‘raw data’ about the outside world
Stimuli can be light, sound, touch, etc.
What are receptor cells?
Specialized cells that receive stimuli in the eyes, ears, skin, nose, tongue, etc.
These cells convert physical energy into neural signals.
What is perception?
Organization and interpretation of sensation
Perception helps the brain make sense of raw sensory data. Known as Top-bottom processing
How do retinal ganglion cells function?
Respond to and enhance contrast, useful for edge detection
They play a crucial role in visual processing.
What does the dorsal stream in the visual system represent?
The ‘where’ pathway related to action
It helps in locating objects in space.
What does the ventral stream in the visual system represent?
The ‘what’ pathway related to perception
It is involved in object recognition.
List the three laws of Gestalt psychology.
- Law of Closure
- Law of Similarity
- Law of Proximity
These laws describe how we perceive patterns and objects.
What is the law of closure?
Organizes perception into whole rather than parts
It helps us complete incomplete figures.
What is the law of similarity?
Like things get grouped together
This law explains how we perceive similar objects as a group.
What is the law of proximity?
Things that are close together get grouped together
This affects how we perceive spatial relationships.
What is object recognition?
Involves sensing different basic features and integrating them into a perceptual whole
It is critical for identifying objects in our environment.
Define top-down processing.
Processing driven by belief and expectations about how the world is organized
It relies on prior knowledge to interpret sensory information.
Define bottom-up processing.
Processing driven by physical input contacting the sensory receptors
It starts with sensory input and builds up to perception.
What is presbyopia?
Age-related farsightedness
It occurs when the lens loses flexibility, making it hard to focus on close objects.