VF: Feedback Tests (sem 1. some of them) Flashcards
A one-way method of limits:
a. is not subject to errors of anticipation or habituation.
b. is subject to errors of anticipation only.
c. is subject to errors of habituation only.
d. is subject to both errors of anticipation and habituation.
d. is subject to both errors of anticipation and habituation.
In classical threshold theory, the function relating stimulus intensity to probability of seeing at a given moment in time is a:
a. step, with a threshold that varies from moment to moment.
b. step, with a threshold that does not change with time.
c. cumulative normal (i.e. S-shaped) distribution, with a threshold that varies from moment to moment.
d. cumulative normal (i.e. S-shaped) distribution, with a threshold that does not change with time.
a. step, with a threshold that varies from moment to moment.
Which of the following stimulus parameters is NOT a factor that affects the critical flicker frequency?
a. Wavelength
b. Intensity
c. Temporal frequency
d. Area
c. Temporal frequency
The Nyquist theorem states that: to adequately sample a signal the sampling frequency should be:
a. at least half the highest spatial frequency in the signal.
b. at least same as the highest spatial frequency in the signal.
c. at least twice the highest spatial frequency in the signal.
d. at least four times the highest spatial frequency in the signal.
c. at least twice the highest spatial frequency in the signal.
Which of the following is NOT an advantage of binocular vision?
a. The two eyes combine to give a larger visual field.
b. Having two eyes means there is a spare should something happen to one.
c. Having two eyes gives enhanced depth perception at long distances.
d. Two eyes are better than one: Binocular summation improves performance for many visual tasks
c. Having two eyes gives enhanced depth perception at long distances.
Visual acuity:
a. is not related to retinal eccentricity.
b. improves with retinal illuminance for both scotopic and photopic vision.
c. improves with age and reaches a maximum at 50 years.
d. is independent of the orientation of the stimulus contours.
b. improves with retinal illuminance for both scotopic and photopic vision.
A motion aftereffect can be induced by:
a. looking at a rock-face next to a waterfall and then at the waterfall, when the water would seem to stand still.
b. looking at a waterfall and then at the rock-face, when the rocks would seem to be moving downwards
c. looking at a waterfall and then at the rock-face, when the rocks would seem to be moving upwards.
d. looking steadily at the waterfall, when the rocks on either side would begin to seem to be moving with the waterfall.
c. looking at a waterfall and then at the rock-face, when the rocks would seem to be moving upwards.
We cannot see the minute-hand of a watch move because:
a. our eye movements are too rapid
b. the low frequency cut-off of our temporal modulation transfer function is too high for that movement
c. the high frequency cut-off of our temporal modulation transfer function is too low for that movement
d. the eye is more sensitive to movement of larger areas
b.
the low frequency cut-off of our temporal modulation transfer function is too high for that movement
Which of the following statements about phorias is INCORRECT?
a. Heterophoria is very common
b. Phorias are often different at distance and near
c. A decompensated phoria is a phoria that is symptomatic
d. Cyclophoria can be corrected with prism
d. Cyclophoria can be corrected with prism
To completely describe a spatial grating stimulus, you must specify its:
spatial frequency, orientation and phase.
spatial frequency, phase and contrast.
orientation, phase and contrast.
spatial frequency, orientation, phase and contrast.
spatial frequency, orientation, phase and contrast.
The vestibulo-ocular reflex:
best stabilizes gaze in response to slow continuously sustained self-rotation
is unique to foveate, frontal eyed species like us
is driven by motion-sensitive ganglion cells in peripheral retina
can be almost perfectly compensatory or can be shut off, depending upon task demands
can be almost perfectly compensatory or can be shut off, depending upon task demands
Which pair of opsin genes share the greatest homology?
L cone opsin and M cone opsin.
If saccades are inadequately inhibited:
A) smooth pursuit may be impossible to generate.
B) fixation should remain undisturbed.
C) normal smooth pursuit may look clinically defective due to the presence of unwanted saccades.
D) it will be impossible to generate reflexive saccades.
C) normal smooth pursuit may look clinically defective due to the presence of unwanted saccades.
Normal smooth pursuit:
A)requires the perception of a smoothly moving object
B)can only be generated when viewing a physical object moving back and forth
C)is essential for normal reading
D)always lags at least 100 ms behind the target
A) requires the perception of a smoothly moving object
Humans make saccadic eye movements throughout their waking lives:
A) because high acuity information about environment only comes in at the fovea so gaze must constantly shift.
B) to identify objects appearing in the periphery that may be potential threats, meals or mates.
C)as occasional corrections to inaccurate smooth pursuit eye movements.
D) all of the other options are correct.
D) all of the other options are correct.
