Sensation and Perception Flashcards
What is the difference between sensation and perception?
Sensation takes information from external sources and converts it into electrical signals in the nervous system
Perception is what is done with those signals– where the information is processed by the CNS to determine how important the information is
What is the absolute threshold, and does it correspond with sensation or perception?
This is the minimum energy a stimulus has to reach to activate a sensory system
Deals with sensation not perception
What is the threshold of conscious perception?
This is the level of intensity required for a stimulus to be consciously perceived by the brain
The stimulus has to reach both the absolute minimum AND the threshold of conscious perception in order for the CNS to be consciously aware of its presence
What is the difference threshold?
Often represented at a percentage, this is the minimum amount a stimulus must change in order for someone to recognize that change
Weber’s law– says there are difference thresholds that are proportional and should be represented as percentages
The two blood vessels of the eye are:
The choroidal and retinal
What does the cornea do?
Gathers and focuses light
Located at the front of the eye
Where are the anterior and posterior chambers located?
Anterior- in front of the iris
Posterior- between the iris and lens
The iris is the _____ part and the ____ is the white
Colored
Sclera
The choroid surrounds the ____ and provides _____
Retina
Nourishment
The lens is located _____ the iris and helps control ______
Below
Light refraction
Rods are used for _____ vision while cones are for _____ vision, and both are located in the _____
Night (black and white)
Color
Retina
The macula is located within the ____ and has the _____ concentration of cones
Retina (right in the middle)
Highest concentration of cones
Explain the anatomical connection between the eyes and brain, and how information is received vs. how/where it’s perceived
The eyes and the brain are crossed. Things on the left side of the body are processed in the right side of the brain. Ex: information received on the nasal side of the right eye stimulates the temporal field of the right eye
Only the ____ fibers cross at the optic chasm
Nasal
This means that something perceived in the right nasal field stimulates the left temporal field, and the left nasal field stimulates the right temporal field
What are the differences between parvocellular and magnocellular cells?
Parvocellular cells allow for high spatial resolution (level of detail), but are only for slow moving or stationary things
Magnocellular cells are very good with fast moving things (high temporal resolution) but don’t have high spatial resolution (high level of details)
