Sensation Flashcards
define sensation
the sense organs gather info about the enviro and transmit the info to the brain for initial processing
5 common features to all sensory systems
- all have receptors
- all require min amount of energy to activate
- require constant decision making
- ability to detect changes
- need to suppress redundant info
absolute threshold
minimal amount of energy must be present for stimulus to be detected 50% of the time
vision - transduction
process of converting physical energy or stimulus info into neural impulses
rods
more light sensitive and cant distinguish colour
cones
need strong light and detailed in vision
found in the centre of the retina
what theory is it when the colour is explained by the activation of the three colour receptors in the eye
trichromatic theory
The magnitude of a stimulus grows geometrically as the subjective experience of intensity grows arithmetically
fechners law
Katie goes to the doctor and the doctor thinks she has broken her
arm. She gets her x-ray back and she has in fact broken her arm. what is this?
hit
Occurs when two or all three of the cones are missing and colour and lightness vision is reduced to one dimension.
monochromacy
opponent-processing theory
once an activated cell is fatigued, you will see the opposite colour
Julie is a radiologist examining a CT scan. As she looks at the scan makes the decision there is no tumor present. It is later found out there was a tumor present. This is an example of a …..?
miss
Stevens power law
As the perceived intensity of a stimulus grows
arithmetically, the actual magnitude of the stimulus
grows exponentially
Webers law
two stimuli, the second must differ by a constant proportion from the first to be perceived as different
Lamelo shoots a buzzer beater shot from halfcourt to win the game. The ref however says it does not count as it was released after the shot clock expired. Upon review it does indeed show that the ball was not released in time. This is an example of a …?
correction rejection
