MCB 461 Final Exam Ques ons and answers Newest
RATED A+ 2025/2026 UPDATED
How does binocular vision develop before birth? - Answers Thalamic inputs represen ng the
le and right eyes segregate from each other to form "ocular dominance" columns of roughly
equal width in the visual cortex
How does binocular vision develop soon a er birth? - Answers During the cri cal period, the
visual experience shapes and combines the representa ons of the 2 eyes in the cortex to make
binocular vision possible
Normal binocular vision consolidates and refines the established pa'erns of ocular
representa on
Depends on correlated pa'erns of ac vity from 2 eyes and convergence of inputs from Layer IV
to III
What happens if you perform monocular depriva on during the cri cal period? - Answers
The LGN axons from the deprived eye in layer 4 will shrink and decrease in synap c strength,
whereas axons from the non-deprived eye expand and increase in synap c strength
What happens if you reinstate normal vision during monocular depriva oN? - Answers This
does not readily restore normal binocular responses in the cortex.
The non deprived eye con nues to dominate the responses of cor cal neurons (even up to 5
years)
A cri cal period of binocular vision - Answers A "cri cal period" to establish binocular
receptor fields
Effects of disrup ons of binocular vision are IRREVERSIBLE when they occur in the cri cal
period. In cats, this begins rapidly at 3 weeks. A er 6 weeks, this period gradually closes.
,What are some mechanisms of binocular plas city? - Answers Modula on of LGN axons that
project to layer 4
Adjust synap c drive by the le and right eyes (NMDA receptor ac va on)
Mechanisms that contribute to synapse forma on or stabiliza on (BDNF, neuromodulators—
acetylcholine, norepinephrine)
PirB or Nogo and its receptors
Precise balance between excitatory and inhibitory inputs
Cri cal period is delayed in GABAA receptor knock out mice
Dark rearing prolongs the cri cal period
Hebbian plas city - Answers Persistent ac va on of a group of simultaneously ac ve neurons
would lead to consolida on of stronger connec on
In response to extrinsic s muli, neurons can change and adapt the strength of their
connec ons. Examples are long term poten a on (LTP) and long term depression (LTD)
Hebbian Plas city is - Answers Associa ve
Rapidly induced
Input specific
Posi ve feedback process
Physiological relevance
Cellular correlate of "learning and memory"
Where does Hebbian synap c plas city happen? - Answers The HIPPOCAMPUS
LTP and LTD are key to forming declara ve memories in the brain
, Pathway from entorhinal cortex - Answers Goes from pyramidal cells in the dentate gyrus to
pyramidal cells in CA3 to pyramidal cells in CA1
Synap c plas city in the hippocampus is the key to forming - Answers Declara ve memories
in the brain
LTP happens at glutamatergic synapses in hippocampus: discovered by - Answers Bliss and
Lomo
Dark circles: POTENTIATED, and their amplitude is higher
In the hippocampus, the EPSP magnitude __________during LTP - Answers Increases
In the hippocampus, the EPSP magnitude _____________ during LTD - Answers Decreases
What's the problem with Hebbian pla city - Answers Eventually, persistently ac va ng
neuronal networks would reach an extreme and become unstable
Homeosta c plas city - Answers Rapid or prolonged process to maintain neuronal firing and
synap c strength *within physiological limit*, thereby preven ng un-restrained increases or
decreases in neuronal ac vity
How does homeosta c plas city work - Answers Induced rapidly or in a long term
Global but unequal scaling
Homeosta c nega ve feedback process
Physiological relevance (Developmental regula on, intraoccular injec on of TTX or dark rearing)
Excitatory inhibitory balance in Vivo
Connec on specific regula on (TTX effect on CA3-CA1 versus CA3 CA3_
Abnormal plas city in disease mechanism
RATED A+ 2025/2026 UPDATED
How does binocular vision develop before birth? - Answers Thalamic inputs represen ng the
le and right eyes segregate from each other to form "ocular dominance" columns of roughly
equal width in the visual cortex
How does binocular vision develop soon a er birth? - Answers During the cri cal period, the
visual experience shapes and combines the representa ons of the 2 eyes in the cortex to make
binocular vision possible
Normal binocular vision consolidates and refines the established pa'erns of ocular
representa on
Depends on correlated pa'erns of ac vity from 2 eyes and convergence of inputs from Layer IV
to III
What happens if you perform monocular depriva on during the cri cal period? - Answers
The LGN axons from the deprived eye in layer 4 will shrink and decrease in synap c strength,
whereas axons from the non-deprived eye expand and increase in synap c strength
What happens if you reinstate normal vision during monocular depriva oN? - Answers This
does not readily restore normal binocular responses in the cortex.
The non deprived eye con nues to dominate the responses of cor cal neurons (even up to 5
years)
A cri cal period of binocular vision - Answers A "cri cal period" to establish binocular
receptor fields
Effects of disrup ons of binocular vision are IRREVERSIBLE when they occur in the cri cal
period. In cats, this begins rapidly at 3 weeks. A er 6 weeks, this period gradually closes.
,What are some mechanisms of binocular plas city? - Answers Modula on of LGN axons that
project to layer 4
Adjust synap c drive by the le and right eyes (NMDA receptor ac va on)
Mechanisms that contribute to synapse forma on or stabiliza on (BDNF, neuromodulators—
acetylcholine, norepinephrine)
PirB or Nogo and its receptors
Precise balance between excitatory and inhibitory inputs
Cri cal period is delayed in GABAA receptor knock out mice
Dark rearing prolongs the cri cal period
Hebbian plas city - Answers Persistent ac va on of a group of simultaneously ac ve neurons
would lead to consolida on of stronger connec on
In response to extrinsic s muli, neurons can change and adapt the strength of their
connec ons. Examples are long term poten a on (LTP) and long term depression (LTD)
Hebbian Plas city is - Answers Associa ve
Rapidly induced
Input specific
Posi ve feedback process
Physiological relevance
Cellular correlate of "learning and memory"
Where does Hebbian synap c plas city happen? - Answers The HIPPOCAMPUS
LTP and LTD are key to forming declara ve memories in the brain
, Pathway from entorhinal cortex - Answers Goes from pyramidal cells in the dentate gyrus to
pyramidal cells in CA3 to pyramidal cells in CA1
Synap c plas city in the hippocampus is the key to forming - Answers Declara ve memories
in the brain
LTP happens at glutamatergic synapses in hippocampus: discovered by - Answers Bliss and
Lomo
Dark circles: POTENTIATED, and their amplitude is higher
In the hippocampus, the EPSP magnitude __________during LTP - Answers Increases
In the hippocampus, the EPSP magnitude _____________ during LTD - Answers Decreases
What's the problem with Hebbian pla city - Answers Eventually, persistently ac va ng
neuronal networks would reach an extreme and become unstable
Homeosta c plas city - Answers Rapid or prolonged process to maintain neuronal firing and
synap c strength *within physiological limit*, thereby preven ng un-restrained increases or
decreases in neuronal ac vity
How does homeosta c plas city work - Answers Induced rapidly or in a long term
Global but unequal scaling
Homeosta c nega ve feedback process
Physiological relevance (Developmental regula on, intraoccular injec on of TTX or dark rearing)
Excitatory inhibitory balance in Vivo
Connec on specific regula on (TTX effect on CA3-CA1 versus CA3 CA3_
Abnormal plas city in disease mechanism
