The Visual System Flashcards
Light travels through which part of the eye thus reflecting onto the retina?
The lens
The retina is comprised of which two types of photoreceptors?
Rods; cones
Rod-mediated vision is referred to as:
Scotopic vision
Cone-mediated vision is referred to as:
Photopic vision
Rod-mediated vision has ___ acuity than cone-mediated vision:
Poorer
Which type of photoreceptor is necessary for vision at night time?
Rods
Which type of photoreceptor is necessary for high-illumination?
Cones
Rods are able to distinguish between different colours. True or false?
False
Our peripheral vision at night tends to be better than our direct vision. This is because our fovea is packed with ___, but contains very few ____:
Cones; rods
Which part of the eye tends to reflect information onto opposite hemispheres?
The optic nerve
ipRGC stands for:
Intrinsically photosensitive retinal ganglion cells
Which type of cell is involved in maintaining our circadian rhythm?
ipRGC
____ transmission occurs when a(n) ____ potential travels down the nerve terminal, causing the release of _____ which then binds to specific ____:
Synaptic; action; neurotransmitters; receptors
Hyperpolarisation is ___ likely to occur than depolarisation:
Less
IPSP is responsible for which two phenomena?
Simultaneous contrast; mach bands
Strong contrast resulting in the high activation of neurons in surrounding regions is referred to as:
Lateral inhibition
Lateral inhibition, the spinning dancer/Mona Lisa illusions and colour afterimage are all examples of:
Opponent processes
According to the electromagnetic spectrum, a ____ frequency is dangerous to the human visual system, whereas a ____ frequency tends to be safer:
High; low
UV rays, x-rays and gamma rays are all examples of ___ frequency radiation, which is dangerous to human vision:
High
Name 3 examples of items that project a low frequency of radiation in accordance with the electromagnetic spectrum:
Microwaves, TVs, radios
Humans have a _____ view, whereas mammals such as cats and dogs have a ____ view:
Trichromatic; dichromatic
What 3 cones give humans a trichromatic view?
Red-light; blue-light; green-light
Males are more likely to be affected by colour blindness than women. True or false?
True
Any self-regulating process whereby organisms maintain stability while adjusting to suitable survival conditions is known as:
Homeostasis
According to the opponent process theory, how we perceive colour occurs as a result of:
Opposing receptor complexes
One opponent process theory, the approach-avoidance theory, involves the human motivation to pursue ____ and avoid ___:
Reward; harm
Most retinal fibres in the human eye are likely to terminate in which part of the thalamus?
The Lateral Geniculate Nucleus (LGN)
In which part of the visual system is the Lateral Geniculate Nucleus (LGN) found?
The thalamus
The crossing over of retinal fibres occurs at the:
Optic chiasm
The mapping of the visual world onto the retina is referred to as:
Retinotopic organisation
V1, Striate cortex and Brodmann’s area 17 are nicknames for which part of the visual system?
The primary visual cortex
_____ cells in the V1 may be monocular or binocular, whereas ____ cells are nearly all binocular:
Simple; complex
Both simple cells and complex cells are orientation selective. True or false?
True
____ organisation helps reduce brain volume by reducing ____ volume, thus resulting in a reduction of axon ____ and allowing room for more _____:
Topographic; axon; length; neurons
