EXAM 3 PSYC 4320
collateral sprouting
If some of the axons innervating a given cell are destroyed or if they become inactive, what compensatory process takes place in the remaining presynaptic cells?
are more sensitive to dim light
In comparison to cones, rods:
obstruction; rupture
Ischemia is to ____ as hemorrhage is to ____.
promotes the survival and growth of the axon
Nerve growth factor (NGF) ____
a greater rod to cone ratio
Night-active species are more likely than day-active species to have:
that ordinarily get input from the dorsal retina
Roger speedy cut a newt's optic nerve and rotated the eye. Axons from what used to be the dorsal part of the retina (now located on the ventral side) grew back to the target areas ___
plasticity
The ability of the brain to change its anatomy over time, within limits, is known as ____.
that a target cell has accepted an axon
What is signaled by nerve growth factor (NGF)?
opsins; photopigments
____ modify the ____ sensitivity to different wavelengths of light.
neurotophins
____ steer new axonal branches and synapses in the right direction
microglia
_____ cells proliferate after a stroke.
photopigments
______ are chemicals that release energy when struck by light
phantom limb
a continuing sensation of an amputated body part is called
synaptic reorganization
a cortical cell originally responded to stimulation of the middle finger. after amputation of that finger, it begins responding to the second and fourth fingers. which action most likely accounts for this?
contrasting the activity in one area of the visual field with that of the others
according to retinex theory, we perceive color by ____
which neurons are active
according to the law of specific nerve energies, the brain tells the difference between one sensory modality and another by _____
our perception of color depends on the relative activity of 3 types of cones
according to the trichromatic theory of color vision _____
relative activity of short, medium and long wavelengths
according to the trichromatic theory of color vision, the most important factor in determining the color we see is the ____
3 kinds of cones
according to the young Helmholtz theory, what is the basis for color vision?
migrate
after cells have differentiated as neurons or glia, they:
uninjured axons to form new branches
after damage to a set of axons, neurotrophins induce nearby _____
weaken
after learning strengthens one set of synapses, other synapses ____
dormant
after maturity, the apoptotic mechanisms become:
dendrites
after the migrating neuron reaches its destination, ____ begins to form
opponent process theory
after you stare at a bright green object for a minute and look away, you see red. which theory attempts to explain this finding?
glutamate
alcohol surprises the reals of ____, the brain's main excitatory transmitter
brain responses that were twice as strong as non musicians
an MEG study of professional musicians listening to pure tones showed that professional musicians had ______
degenerate and die
an axon that does not receive enough neurotrophins from a target cell will ____
is a programmed mechanism of cell death
apoptosis
increase the branching of axons
at later stages of the neuron's development, neurotrophins _____
trichromatic; oponent process
at the level of rods and cones, the ____ theory seems to fit best, while at the level of bipolar cells, the _____ theory of color vision
ganglion cells
bipolar cells send their messages to _____, which are located close to the center of the eye
stem cells
brain cells that are neither neurons nor glia, but which are capable of dividing and then differentiating into neurons or glia, are called:
using a chemical gradient
chemicals in the amphibian tectum guide the growth of axons from the retina to their correct location in the tectum by :
immunoglobulins; chemokines
chemicals known as ____ and ____ guide neuron migration
photopigments
chemicals that release energy when struck by light are called ____
the most common cause of brain damage in young adults
closed head injury is _____
rotational forces that push the brain against the inside of the skull
closed head injury results in damage partially because of _____
retinex
color and brightness constancy are best explained by the ___ theory of color vision
recognize the color of an object despite the changes in lighting
color constancy is the ability to _____
neural darwinism
concept that neurons refine their Many connections based on which ones are most successful is known as:
breaks up blood clots
damage due to stroke caused by ischemia can be minimized by administering a drug that _____
immature neurons experimentally transplanted from one part of the developing Cortex to another _____.
develop the properties characteristic of their new location
decreased activity of surviving neurons after other neurons are damaged
diaschisis refers to the _____
red; green
difficulty distinguishing between ___ and ___ is the most common form of color vision deficiency
tub surrounding a fluid filled cavity
early in development, the nervous system begins as a:
ventricular system
fluid filled cavity of the developing neural tube becomes the:
extreme overlap of cortical representation of the fingers
focal dystonia, sometimes called musician's cramp, is caused by ______
synaptogenesis
formation of new synapses is called:
denervation supersensitivity
heightened sensitivity to a neurotransmitter after the destruction of an incoming axon is known as _____
unknown, therefore abstention is recommended
how much alcohol can a pregnant woman drink without worrying about the negative effects on her child?
more responsive
if most of the axons that transmit dopamine to some brain area die or become inactive, the remaining dopamine synapses become _____
the fovea
if you want to see something in fine detail, you should focus the light on which of your retina
sensitive to detail
in comparison to the rods, cones are more _____
preserve neurons; increase neural branching
in development, neurotrophins ____. during adulthood, they ______.
increase regrowth of damaged axons
in response to nervous system injury, neurotrophins
bipolar cells
in the human retina, messages go from receptors at the back of the eye to _____.
to bipolar cells within the retina
in vertebrate retinas, the receptors send their messages ____
receptor cells, bipolar cells, ganglion cells
in what order does visual information pass through the retina
all trans retinal
light energy converts 11-cis-retinal to _____
pupil
light enters the eye through an opening in the center of the iris called the ____
the left half
light from the right hand of the world strikes which part of the retina
a precise chemical environment
migration requires:
continues well into the adult years
myelination in the human brain ____
is a programmed mechanism of cell death
necrosis
is cell death caused by an injury or a toxic substance
necrosis ____
have the amputee learn to use an artificial limb
one way to relieve the pain associated with a phantom limb is to _____
rods
peripheral vision mainly depends upon _____
production of new cells
proliferation is the:
shortly before the stroke
research on laboratory animals indicates that cannabinoids are most effective if taken _____
the peripherally; the fovea
rods are to ____ as cones are to ____
2 types of long wavelength cones
the ability of some women to detect slightly finer discriminations of color than other women is likely due to having ____
be thicker
the areas of the cortex used by expert video game players are most likely to ___ than the same cortical areas of those who do not play video games
trichromatic
the fact that all colors on older TV's were created by combining only 3 different colors of light support the _____ theory of color vision
promote survival of axons
the function of neurotrophins is to _____
every stimulation of the optic nerve I perceived as light
the law of specific nerve energies states that _____
apoptosis
the mechanism of fetal alcohol syndrome relates to
blind spot
the name of the point at which the optic nerve leaves the retina is called the ________
ganglion cells
the optic nerve is composed of axons from which kind of cell
have a greater density of receptors than do humans on the top half of the retina
the retinas of predatory birds such as hawks ______
amacrine cells
various types of ____ cells refine the input to ganglion cells enabling them to respond specifically to shapes, movement of other visual feature
glia releasing chemicals that inhibit axon growth
what is one impediment to the regeneration of axons in the mammalian central nervous system?
differentiation
what is the process called when a primitive neuron begins to develop dendrites and an axon:
iodized salt
what modern day practice helps prevent an inadequate production of thyroid hormones
both axons and target cells
which are selective as axons form synapses with target cells
they follow chemical gradients from the target cell
which best characterizes how axons arrive at the correct target cells
chemical attraction
which best describes the process by which developing axons find their general target areas
ischemia from an obstruction of an artery
which event is the most common cause of a stroke
engaging in physical activity
which factor appears to be particularly important for branching of neurons during brain development
cones only
which receptors are responsible for the perception of color
it has the greatest perception of detail
which statement characterizes the fovea?
it is easier to recognize single objects in the peripherally that are not surrounded by other objects
which statement is TRUE with regard to peripheral vision
far more neurons are produced than will ultimately survive
which statement most accurately describes embryonic development of the nervous system in humans?
retinex theory
which theory can best explain why people that are wearing yellow colored glasses can still identify the color of a green apple
opponent process theory
which theory of color vision is best able to explain negative color afterimages?
giving stimulant drugs combined with physical therapy
which treatment would be most likely to help a patient starting it several days after a stroke
more receptors in the peripherally than in the fovea funnel input to each ganglion cell
why do humans perceive faint light better in the periphery of the eye?
it has tightly packed receptors
why does the fovea provide the clearest, most detailed visual information
if an axon does not make the appropriate connections by a certain age, it dies
why is it that all neurons in a healthy adult brain have made appropriate connections
axons that fail to find a target cell die
why is it that every axon in an adult mammal has a target cells with which it makes synaptic contact?