Neuro-thalamus

what type of matter is the thalamus?

gray

how is the collection of nuclei within the thalamus distinguished?

pattern of connections

what type of matter is the thalamus?

gray

how is the collection of nuclei within the thalamus distinguished?

pattern of connections

what are the 3 types of thalamus nucleus?

relay

association

non specific

what is the relay nuclei of the thalamus?

bidirectional connections of sensory cortices

motor control circuit units

what does the association nucleus have connections to?

limbic and association cortices

what does the non-specific nucleus of the thalamus deal with?

arousal of alertness

what is the connection of the non-specific nuclei?

to other thalamic nuclei

what is the thalamus' role in relay?

sensory input passes through unmodified to the targeted region of cortex

what is the gateway role of the thalamus?

decision is made about what input is going to be passed along to the cortex

what is the relay neuron within the thalamus?

principal

what relay neuron is glutamatergic?

principal

where does the principal neuron synapse?

cortex

what is the job of the principal neuron?

convey sensory input to the thalamus from the various receptor organs

what releases glutamate?

NTM of 3rd motor neuron releases at synaptic terminals for receptors

what does it mean that the thalamic relay neuron is bistable?

can exist in 1 or 2 states (can switch, but no middle ground)

what are the states that the thalamic relay neuron can be in?

1. tonic

2. burst

when does tonic firing occur?

awake

what does tonic firing do to membrane potential?

depolarization- EPSP

when does burst firing occur?

sleep drowsiness inattention bored (some wakefulness)

what does burst firing do to the membrane potential?

hyperpolarize

what is the apprx membrane potential of tonic firing?

-60mv

what is the apprx membrane potential of burst firing?

-70mv

what mode is faithfully encoded and what does this mean?

tonic- accurate transimission of detail w/o sig loss in details

what mode pertains to becoming later?

burst

what is neuromodulation?

the physiological process by which a given neuron uses one or more chemicals to regulate diverse populations of neurons

when can information get through burst tone?

important and strong enough

what does the resting membrane potential of relay cells result from?

leak and VG channels

what modulates the resting membrane potential of relay cells?

metabotrophic glutamate receptors

dopamine

NE

where do the neuromodulators arise from?

cortex thalamus reticular outputs

what can influence gating factor of thalmaus?

experience to be trained

what is state of message during burst mode?

message to cortex is bigger, temporal summation

what artery can lead to thalamic CVA?

thalamogeniculate

what body parts does thalamic syndrome effect?

contralateral body and head

what are side effects of thalamic syndrome?

hemianstheia sensory ataxia thalamic pain

what is thalamic pain?

severe contralateral pain with/without provoking stimulus