Sensation
The physical process of collecting data from the environment via the senses
Perception
The cognitive process of interpreting data once it has been sensed
Constancies (2)
- Shape constancy- our tendency of seeing an object keep its shape even when seen from different angles
- Colour constancy- our tendency to see colours remaining the same despite differences in lighting
Depth perception
The ability of our eyes and brain to add a third dimension to everything that we see
Depth cues (5)
- Linear perspective- lines converging in the distance
- Height in plane- Objects ‘higher’ are further away
- Relative size- how big things are in comparison to one another
- Superimposition- objects ‘blocking’ one another
- Texture gradient- less defined texture with distance
The Constructivist theory of perception
- The theory that perception is constructed using past experiences
- Supports Top-down processing
- Perceptual set
1. Expectations
2. Motivation
Top-down processing
When perception is dominated by what we expect to see
Perceptual set
A tendency to perceive something in line with what you expect based on past experience
P Constructivist theory evaluation (3)
- If perception is based on previous experience, this doesn’t explain why people tend to perceive the world in a similar way- suggests that the information is from our environment
- If perception relies on previous experience, how do you explain a baby’s ability to perceive the world as they are shown to have a perceptual set early on
- The effect of illusions weakens the constructivist theory as it would suggest that we would learn not to fool for the same illusion twice- but we often do
P Alternative theory:
Nativist theory
- Perception is a result of bottom-up processing
- Perception is immediate and data-driven
- We have all evolved in the same way and so perceive our world in a similar way
Bottom-up processing
When perception is dominated by what enters through the eyes
Haber and Levin (2001)
- Procedure: Repeated measures design using 9 male college students with good eyesight. Estimating the distance to objects in three sections- 1) Objects of known size, 2) Objects of unknown size & 3) Geometric figures
- Results: Estimates were best for objects of known size
- Conclusion: Participants relied on past experiences to estimate the distances (supporting top-down processing, constructivist theory)
Haber and Levin (2001) evaluation (3)
- Unrepresentative sample cannot be generalised for the rest of the population
- Low ecological validity due to artificial and unfamiliar task and setting, doesn’t relate to real life
- How familiar the objects were to the participants is subjective, may’ve been a coincidence that known objects were more accurately perceived.
Perception applications of research:
Advertising
Placement of adverts: Food adverts shown during a time where viewers are likely to be hungry means that they are likely to be better perceived > constructivist theory of motivation
