Introduction to Perception Flashcards
What is the definition of perception?
Psychological processes through which we gain knowledge of the world via our senses.
Around how many visual cortical areas do we have?
30
Why does perception seem so easy to us?
We have so much neural circuitry.
How many photoreceptors do we have in each retina?
100 million
How many cells do we have in each cortex of the brain?
100 billion
Each nerve cell makes ____ connections to other cells?
4000
The oldest branch of experimental psychology is based on the ideas of which two psychologists?
Weber (1834) and Fechner (1860)
A central concept of perception is ________ ?
Thresholds (limits of perception)
What is a detection threshold?
The weakest stimulus needed to evoke a response.
What is a discrimination threshold?
The smallest difference between 2 stimuli along a dimension that can be detected.
Measuring detection thresholds: What is the method of limits?
Changing the stimulus strength until subject says it is just detectable/undetectable.
Measuring detection thresholds: What is the method of adjustment?
When the subject changes the stimulus strength until it is just detectable/undetectable.
Measuring detection thresholds: What is the method of a constant stimulus?
When the subject is presented with a constant set of stimulus strengths in a random order and are asked if they can detect it.
What is used to rule out the subject being biased or lying when measuring detection thresholds?
Forced choice task.
What happens during a forced choice task?
- Subject is asked to report something about the stimulus.
- In each trial, the stimulus is presented at one of two temporal intervals.
- The subject responds either ‘first’ or ‘second’.
- The percentage of correct responses is calculated and the threshold.