Perception - Unit 2 Flashcards
Sensation
Physical stimulation of the sensory receptors is processed by sense receptors which or brain interprets to lead to perception.
Perception
The organisation and interpretation of sensory information.
What is the difference between sensation and perception?
Sensation is the detection of a stimulus in the environment whereas perception is the brain interpreting and understanding these sensations.
Visual cues
Features of the environment that give us information about movement, distance etc.
Visual constancies
Seeing objects is the same despite seeing them from different angles and distances.
Give two examples of binocular depth cues
Retinal disparity
Convergence
What is retinal disparity
- each eye sees things differently as they are positioned about 6cm apart on the face.
- retinal disparity is the difference between the left and right eye’s view which the brain receives to give information about depth and distance
What is convergence
- Our eyes converge/become closer together when objects get closer to us.
- Muscles around our eyes work harder when objects are close and this information is sent to the brain to give information in depth and distance
Give four examples of monocular depth cues
- Height in plane
- Relative size
- Occlusion
- Linear perspective
What is height in plane
Objects that are higher up in the visual field appear to be further away
What is relative size
Small objects in the visual field appear further away
What is occlusion
Objects that are in front of others appear closer to us whilst objects behind other objects seem further away
What is linear perspective?
When parallel lines converge in the distance, the point at which they come together is perceived to be further away.
What are the 4 main explanations fo visual illusions
Size constancy
Misinterpreted depth cues
Ambiguous figures
Fiction
Describe size constancy as an explanation for visual illusions.
The brain perceives familiar objects as a constant size despite the size of the image they produce on our retina changing with distance
Describe misinterpreted depth cues as an explanation for visual illusions
Objects in the distance that appear smaller are scaled up by our brain so that they look normal size.
Sometimes the brain perceives distance where there isn’t any which creates a visual illusion.
Describe ambiguous figures as an explanation for visual illusions
A type of visual illusion where there are two possible interpretations of the same image and the brain cannot decide which one to choose.
Describe fiction as an explanation for visual illusions
A type of visual illusion that causes the brain to perceive something that is not there.
Give 6 examples of visual illusions
Ponzo illusion Müller-Lyer illusion Necker cube Kanizsa triangle Ames room Rubin’s vase
Explain Ponzo’s Illusion
MISINTERPRETED DEPTH CUES
Converging lines create the illusion of distance, the brain uses size constancy and mentally scales up the more distant line and scales down the closer line
Explain Müller-Lyer illusion
MISINTERPRETED DEPTH CUES
I going fins are shaped like the outside of a building and outgoing fins are shaped like the corner of a room stretching away from us.
This gives the illusion of distance and so we mentally scale up the line that appears closer (outgoing fins) so it appears longer.
Explain necker cube
AMBIGUOUS FIGURES
The same image of the cube can be perceived as pointing upwards to the right or downwards to the left