Introduction to Perception Flashcards
What is perception?
Conscious experience resulting from stimulation of the senses
What is sensation?
Simple processes at the beginning of a sensory system and detecting elementary properties
What are the steps of the perceptual process?
- Stimulus in the environment (distal + proximal)
- Light is reflected and focused
- Receptor processes
- Neural processing
- Recognition
- Action
What is distal stimuli?
Something in the environment being observed
What is proximal stimuli?
Representation of the stimuli on receptors
What is the principle of transformation?
Stimuli and responses are transformed or changed between the distal stimulus and perception
What is the principle of representation?
Perception is not based on direct contact with stimuli but rather everything we perceive is based on representations of the stimulus that are formed on receptors and the resulting activity in the nervous system
What is the first transformation in the principle of transformation (vision)?
Light hits an object and is reflected into a person’s eyes
What is the second transformation in the principle of transformation (vision)?
As light enters the eye, it is transformed as it is focused by the eye’s optical system which forms an image on the receptors of the retina
What are sensory receptors?
Cells that respond to environmental energy
What are receptor processes?
Receptors transform environmental energy into electrical energy
Receptors shape perception by the way they respond
What is transduction?
Transforms energy in one form to another
What is neural processing?
Transmits signals from receptors to the brain
Processes signals as they are transmitted
What are behavioural responses?
Electrical signals are turned into conscious experience
What is action?
Taking action towards a perceived object
What is bottom-up processing?
processing based on stimuli reaching the receptors
What is top-down processing?
Refers to processing based on knowledge
What are the 3 types of relationships in perceptual processing?
Relationship A: stimulus-perception
Relationship B: stimulus-physiological
Relationship C: physiological-perception
What is the oblique effect?
People can see vertical or horizontal lines better than lines oriented obliquely
What is the stimulus-behaviour relationship and how is it studied (oblique effect?
Relates stimuli to behavioural responses
Studied using psychophysics - grating acuity for studying the oblique effect
What is the stimulus-physiology relationship and how is it studied (oblique effect?
Relationship between stimuli and neural firing
Study by measuring brain activity - optical brain imaging, presenting lines in various orientations for oblique effect
What is the physiology-behaviour relationship and how is it studied (oblique effect)?
Relates physiological responses and behavioural responses
Measure brain response and behavioural sensitivity in same subjects
-made by decreases the intensity difference of a grating until the subject could no longer detect the gratings orientation and fMRI is also used
What are thresholds?
Measure the limits of sensory systems which are measures of minimums
What is psychophysics?
The study of the relation between mental physical properties
What is the method of limits?
The experimenter presents stimuli in either ascending or descending order until the threshold is reached
What did classical psychosocial methods do?
Opened the way for the founding of scientific psychology by providing methods to measure an aspect of the mind
What is the absolute threshold?
The smallest stimulus level that can just be detected
What is the difference threshold?
The smallest difference between two stimuli that enables us to tell the difference between them
What is the dark adaptation curve?
Shows how the threshold becomes smaller as the person spends more time in the dark
What is the perceptual magnitude of a stimulus (technique)?
Magnitude estimation - present a stimulus and ask participants to assign a number that is proportional in other stimulus environments (2 lights double as bright?)
What is the identity of the stimulus (technique)?
Recognition testing
How quickly can I react to it (technique)
Reaction time
How can I describe what is out there (technique)?
Phenomenological report
-describing what is out there
Hermann grid
-describing what you see
How can I interact with it (technique)?
Physical tasks and judgements
