Sensation and Perception Flashcards
What is synesthesia?
A crossing over of senses (could be harmful or beneficial)
Give an example of something people with color-grapheme synesthesia would do?
Associating numbers with colors.
Describe the beginning of sensation
Sense organs translate the representation of stimuli.
What is transduction?
Converting a stimulus into nerve impulses.
What is a feature detector?
A certain neuron the responds to a specific stimuli (eg. only responding to straight lines)
Give a brief definition of perception.
Giving meaning to and organizing stimuli, often by recalling a memory. (eg. recognizing someone’s face)
What heavily influences the interpretation of a stimuli (perception)?
Context
What is a way we measure perception and explain this method
Using psychophysics which involves the relationship between a physical stimuli versus how we perceive it.
Define absolute threshold
The amount of a signal that must be provided for an observer to sense it.
Define difference threshold
Lowest amount of change for an observer to sense it.
Describe what a decision criteria is?
How certain we must be before we recognize that a stimulus is present (eg. deciding when we are in danger)
What does signal detection theory address?
What factors affect sensory judgments (eg. being tired/awake)
Define Weber’s Law
Difference threshold is directly proportional to the stimulus with which the comparison is being made. (eg. adding 1 gram to 50 grams could be noticeable but adding 1 gram to 500 grams isn’t)
Define sensory adaptation/habituation?
Diminishing sensitivity in an unchanged environment
What is the cornea?
Transparent protective layer at the front of the eye.
What is the pupil?
Adjustable portion behind the cornea the affects how much light enters (controlled by the iris)
What is the lens?
Elastic structure that changes form to focus
Describe the retina
A multi layered structure at the back of the eye that contains light sensitive photoreceptors which turn light energy into electrical impulses
How can myopia occur in people (nearsightedness)?
Light is focused in front of the retina
How can hyperopia occur (farsightedness)?
Light is focuses behind the retina
Describe rods
A photoreceptor that contributes to vision in the dark and black and white. Found everywhere except for the fovea.
Describe cones
A photoreceptor used for seeing color in light and only found in the fovea.
Describe transduction from the eyes
Bipolar cells receive signals from the rods and cones and then synapse with the ganglion cells and then the signal is sent to the optic nerve.
What is the purpose of horizontal and amarcrine cells?
They modulate the movement of signals across their pathway
How does the blind spot occur?
The axons that form the optic nerve have no photoreceptors so that gap where the signal leaves the eye is a blind spot.