MCAT Biology Sensation and Perception Part 2 Flashcards
What is the function of the vestibular complex?
The vestibular complex function to detect rotational acceleration
The Vestibular complex is made up of ___,___,__,__
Three semicircular canals,
The utricle
The saccule
The ampullae
Light is ___ as it passes through the cornea
Refracted
The pigmentation of cells here absorbes excess light within the eye
Choroid (contains darkly pigmented cells)
___ is the surface upon which light is focused
Retina
The role of this part of the eye is to fine-tune the anlge of incoming light, so that beams are perfectly focused upon the retina
lens
The curvature of the lens (its refractive power) is vaired by the __
ciliary muscle
The retina contains ___ and __ which are responsible for detecting light
Rods and cones
The rods and cones located in the retina synapse with nerve cells called__
bipolar cells
Bipolar cells synapse with ___ whose axons comprise the optic nerve
Ganglion cells
The point on the retina where many axons from ganglion cells converge to form the optic nerve is the __
optic disk
Why is the optic disk known as the blind spot?
It contains no photoreceptors
In the center of the ___ is the fovea centralis
Macula
The fovea centralis contains only___
cones
The fovea centralis (focal point) is responsible for __
Extreme visual acuity
The special pigment proteins of photoreceptors is termed ___
opsin
Night vision is accomplished by the ___
rods which are more sensitive to dim light and motion
Rods are more concentrated in the ___
periphery of the retina
___ require abundant light and are responsible for color vision and high acuity vision
Cones
Cones are more concentrated in the ___
fovea
What three colors are specialized cones working with?
Blue absorption green absorption and red absorption
Normal vision is termed___
emmetropia
Too much curvature of the cornea or lens causes___
light to be bent too much and to be focused in front of the retina
Too much refraction at the lens or an abnormally long eyeball results in a focal length that is too short
Myopia
Myopia can be corrected by a ___ lens
Concave (diverging) lens
What does a concave (diverging) lens do?
Cuases the light rays to diverge slightly before they reach the cornea
___ farsightedness results from focusing of light behind the retina
Hyperopia
Too little refraction at the lens or an abnormally short eyeball results in a focal length that is too long
Hyperopia (farsightedness)
Hyperopia (farsightedness) can be corrected by a
Convex (converging lens)
__lens causes light rays to converge before reaching the cornea
Convex( converging)
__ is an inability to accomodate (focus)
Presbyopia
___ results from loss of flexibility of the lens, which occurs with aging
Presbyopia
___ is the term to describe how many aspects of a visual stimulus (such as form, motion, color, and depth) are processed simultaneously instead of in a step-by-step or serial fashion
Parallel processing
____explains why a certain area of the brain is activated when looking at a face, a different area is activated when looking at the letters on this page, etc.
Feature detection theory
As we age we lose our ability to detect higher-pitched sounds, why tho?
Loud sounds can mechanically harm the hair cells, causing them to die. When this occurs, hair cell cant send sound signals to the brain. Once they die they never regrow
The ___ is the minimum noticeable difference between any two sensory stimuli, 50% of the time
JND just noticeable difference or Difference threshold
___ dictates that two stimuli must differ by a constant proportion in order for their difference to be perceptible
Weber’s Law
A hit, by definition of signal detection theory refers to when
The signal is present and was detected
A miss by definition of signal detection theory refers to when__
The signal was present but not detected
A false alarm by definition of signal detection theory refers to when___
The signal was not present but the person thought it was
A correct rejection by definition of signal detection theory refers to when__
The signal was not present and the person did not think it was
The four possible outcomes of signal detection theory are_
- a hit
- a miss
- false alarm
- correct rejection
__attempts to predict how and when someone will detect the presence of a given sensory stimulus
Signal detection theory
