Sensory Systems Flashcards
Light enters the human eye through an opening in the iris called the
Select one:
a. retina
b. pupil
c. cornea
d. fovea
b. pupil
In humans, all of the visual receptors are in the
Select one:
a. last layer of the retina to be reached by light entering the eye
b. middle neural layer of the retina
c. first layer of the retina to be reached by light entering the eye
d. cornea
a. last layer of the retina to be reached by light entering the eye
In comparison to the photopic system, the scotopic system has more
Select one:
a. rods
b. receptors in the periphery of the retina
c. sensitivity in dim illumination
d. all of the above
d. all of the above
The brightness of a light depends on its
Select one:
a. intensity
b. wavelength
c. colour
d. both A and B
d. both A and B
The retina-geniculate-striate system is organized
Select one:
a. from top to bottom
b. from left to right
c. on the basis of wavelength
d. retinotopically
d. retinotopically
The receptive field of a visual neuron is the area of the
Select one:
a. striate cortex within which stimulation can activate the neuron
b. retina within which stimulation with diffuse light can activate the neuron
c. striate cortex within which stimulation can inhibit the neuron
d. visual field within which the suitable visual stimulus can influence the firing of the neuron
d. visual field within which the suitable visual stimulus can influence the firing of the neuron
Posterior parietal cortex is considered to be association cortex because it receives substantial sensory input from the
Select one:
a. hypothalamus
b. secondary areas of more than one sensory system
c. thalamus
d. primary visual cortex
b. secondary areas of more than one sensory system
Connections between various areas of visual cortex are virtually always
Select one:
a. excitatory
b. unidirectional
c. reciprocal
d. inhibitory
c. reciprocal
A major principle of sensory system organisation is
Select one:
a. hierarchical organization
b. functional segregation
c. parallel processing
d. all of the above
d. all of the above
The auditory system is organised
Select one:
a. retinotopically
b. tonotopically
c. somatotopically
d. geographically
b. tonotopically
What are the amacrine and horizontal cells specialised for?
Lateral communication
Do rod-fed circuits have a high or low convergence?
High; Lots of rod cells to one retinal ganglion cell
The _______ are donut-shaped bands of contractile tissue that regulates the amount of light that reaches the retina
Irises
Prey animals have _______ eyes, which allow them to see the predators approaching from most directions due to a larger field of vision
Side-facing
_______ is the difference in the position of the same image on two retinas
Binocular disparity
Amacrine cells and horizontal cells are responsible for _________ communication
Lateral
______ is the process of perceiving large surfaces by extracting information about the edges and making inferences about the shape from it
Surface interpolation
In scotopic vision, hundreds of _________ converge on a single retinal ganglion cell
Rods
The majority of the visual neurons respond only to _______ images
Changing
Rhodopsin is a _______ receptor that does not respond to neurotransmitter molecules
G-protein-coupled
The path that all the signals take to reach the right primary visual cortex from the left visual field is either _________ or contralateral
Ipsilateral
What are Mach band and what do they demostrate?
Mach bands are a series of homogeneous stripes of different intensity. They demostrate an illusion where adjacent to each edge, the brighter stripe looks brighter than it really is and the darker stripe looks darker than it really is
The area of the visual field within which it is possible for a visual stimulus to influence the firing of that neuron is called what?
Receptive field
What is the absorption spectrum?
a graph of the ability of a substance to absorb light of different wavelengths
What is accommodation?
the process of adjusting the configuration of the lenses to bring images into focus on the retina
What is acuity?
the ability to see the details of objects
What is agnosia?
a failure of recognition of sensory stimuli that is not attributable to a sensory or to verbal or intellectual impairment
What is akinetopsia?
a deficiency in the ability to see movement progress in a smooth fashion, which often results from damage to the MT area
What are amacrine cells?
retinal neurons that are specialised for lateral communication
What is an association cortex?
an area of the cortex that receives input from more than one sensory system
What is the auditory nerve?
the branch of the cranial nerve VIII that carries auditory signals from the hair cells in the basilar membrane
What is the basilar membrane?
the membrane of the organ of Corti in which the hair cell receptors are embedded
What does binocular mean?
cells in the visual system that are binocular respond to stimulation of either eye
What is binocular disparity?
the difference in position of the same image on the two retinas
What are bipolar cells?
bipolar neurons that form the middle layer of the retina
What is the blind spot?
the area on the retina where the bundle of axons from the retinal ganglion cells leave the eye as the optic nerve
What is blindsight?
the ability to respond to visual stimuli in a scotoma without conscious awareness of those stimuli
What are blobs?
peglike, cytochrome oxidase-rich, dual-opponent colour columns
What are ciliary muscles?
the eye muscles that control the shape of the lenses
What is the cochlea?
the long, coiled tube in the inner ear that is filled with fluid and contains the organ of Corti and its auditory receptors
What is colour constancy?
the tendency of an object to appear the same colour even when the wavelengths of light that is reflects chance
What is the “control of behaviour” versus “consciour perception” theory?
the theory that the dorsal stream mediates behavioural interactions with objects and the ventral stream mediates the conscious perception of objects
What are complementary colours?
pairs of colours that produces white or grey when combined in equal measure
What is completion?
the visual system’s automatic use of information obtained from receptors around the blind spot, or scotoma, to create a perception of the missing portion of the retinal image
What are complex cells?
neurons in the visual cortex that respond optimally to straight-edge stimuli in a certain orientation in any part of their receptive field
What is component theory?
the theory that the relative amount of activity produced in three different classes of cones by light determines its perceived colour (also called trichromatic theory)
What are cones?
the visual receptors in the retina that mediate high acuity colour vision in good lighting