Lecture 5: Perception Mechanisms (Vision only) Flashcards
does not produce an accurate internal copy of the external world
vsiual system
eyes are “tricked” into seeing things the way they aren’t; regarded as minor imperfections to one’s vision
visual illusions
Electromagnetic radiation that can be perceived by the human eye (visible light spectrum)
light
light is sometimes defined as waves of electromagnetic energy between ______
380-760 nm
if there is no light, there is no _____
vision
2 notable properties of light
- wavelength
- intensity
plays an important role in the perception of color
wavelength
plays an important role in the perception of brightness
intensity
The amount of light reaching the retinas is regulated by the ____
iris
donut-shaped bands of contractile tissue
iris
the hole in the iris
pupil
light enters through the _____
pupil
Adjustment of pupil size in response to changes in illumination represents a compromise between
- sensitivity
- acuity
ability to detect the presence of dimly lit objects
sensitivity
ability to see the details of objects
acuity
happens during high level of illumination
constriction of pupils
happens during too low level of illumination to activate the receptors
dilation of pupils
Focuses incoming light on the retina
lens
When gaze is directed at something near, the lens assumes its
natural cylindrical shape
On a distant object, the lens is
flattened
process of adjusting the configuration of the lenses to bring images into focus on the retina
accomodation
the difference in the position of the same image on the two retinas
binocular disparity
functions of the retina
- Converts light to neural signals
- Conduct them towards the CNS
- Participates in the processing of the signals
5 types of neurons in the retina
- receptors
- horizontal cells
- bipolar cells
- amacrine cells
- retinal ganglon cells