cogs 107a final

labeled line model

each cell represents a taste quality and communicates info to the CNS separate afferent pathways to the gustatory corext

one odor** receptor cell but each receptor responds to a range

each olfactory sensory neruron expresses

10th (vagus) cranial nerve

epiglottis and down into gut

how is vertical cleft formed

even amount of notch 1 and numb

what happens if K channels are blocked from PKA low gK

extended depolarization prolongs the action potential - more ca comes in - more transmitters

5 prolific positions

extension migration - DNA replication return to ventricular surface retraction divison (stay or go)

ionotropic

fast and brief mediates behavior

advantages of working with invertebrates

small nervous systems large neurons identifiable neurons and circuits simple genetics

supporting cells

similar to glia help produce mucus

olfactory receptor cells

site of transduction

metabotropic

slow and lasts long changes quality of behavior

other things that help you taste

tongue mouth palate pharynx epiglottis

analog signal intensity

transformed into a digital pulse code

circumvallate

type of papilla

thalamus regions

ventral posterior medial (bottom, back, midline) -

how to communicate sensory info

- receptor cells make contact sensory axons from CN 10, 9, 7

cell activated during associtie learning

5HT

NMDA is a function of

AMPA

purinergic

Atp receptors are called

how does cAMP effect protein kinases A

Causes subunits to dissociate

CNS

Cb1 is in the

what mediates bitter

G Protein coupled receptor families (GPCRs) type 2 ATP

transduction mechanism for bitter, sweet, umami

G protein activates phospholipase -c increases synthesis of IP3 OP3 triggers release of Ca, and taste specific Na channel opens membrane depolarizes and xmtr releases(ATP) diffuses through ATP permeable channels

no

are taste receptor cells neurons

NMDA channels

Mg acts as a voltage sensor at resting membrane potential, Mg++ is stuck in the channel as the membrane is depolarized (flow of ions in AMPA) Mg is dislodged and the current can flow NMDA is also permeable to Ca++ magnitide of Ca is proportional to the co activation levels of the pre and post synaptic cells at the synapse

Hebbian learning rule #2

Neurons that fire out of sink lose their link

role of creb

PKA phosphorylates creb is a transcription factor helps to grow new synapses

facial nerve (7) anterior part of tongue

PNS can have fibers that do different functions - somatic - movement - special sensory - taste

CB2

PNS, immune, and metabolic

NMDA acts like

a voltage sensor (mg block)

ventrical zone

above ventricular surface

coincidence detector

adenylyl cyclase acts like a __________ in classical conditioning

1 olfactory nerve

alfactory system is mediated by this cranial nerve

receptor potential

amplitude and duration tells us about the stimulis

7th (facial) cranial nerve

anterior (tip) of tongue

taste receptor cells

apical near surface of the cell chemically sensitive to TRC microvilli project into the pore synapse onto gustatory afferent axons chemical and electrical synapses onto basal cells

3 phases of pathway formation

axon chooses the correct path (cross or stay the same) determine where to stop (target) must synapse at the correct spot (info you transmit should be meaningful)

marginal zone

below pial

induction of LTP

biochemical reactions that come out of tetanic stimulation

olfactory receptor cells are

bipolar olfactory neurons penetrates into CNS axons bundle and become cranial nerve

CREB 1

cAMP response element binding protein

what makes adenylyl cyclase

ca binding to calmodulin

molecular basis for clasical conditioning in Aplysia

ca is elevated and adenylyl cyclase increases cAMP more cAMP- more PKA - phosphorylates K channels -- decreases K current decreased gK-- prolonged AP-- more CA is released increased post synaptic response

why does sensory neurons activity have a specific effect on sensory experience

central connections not bc of taste receptor that evokes the activity

what do classes of receptor cells do

changes one type of stimulus into electrical signals that are encoded as action potentials

pain

chemo and mechano

4 types of guidance mechanisms

chemoattraction - contact and attraction - netrin chemorepulsion - contact and repulsion - slit and robo

transforms smell, taste

chemoreceptor

what determines if daughter cells stay or go

cleavage plane determines distribution of transcription factors vertical - both stay and replicate horizontal - top daughter migrates

how we perceive complex flavors

combination of chemoreceptors with different strengths for ligands

subplate

contains the first neural precursor cells to migrate from the ventricular zone and is transient

papilla

contains the tastebuds

habituation and importance

continued stimulus lessons the response learns what it can safely ignore important for

endocannabinoid system

controls excitatory behavior on a synapse by synapse level

types of memory

declarative -- facts, events, places cerebral cortex (conscious memory formation) procedural -- motor skills, habits striatum/ basal galglia

long term habituation is caused by

decrease in amount of synaptic contacts between sensory and motor neurons

important parts of the hippocampus

dentate gyrus - direct pathway -CA1 neuron layer 3 of Entorhinal cortex -trisynaptic pathway - different part of CA1 layer 2 of Entorhinal cortex perferant pathway

ubicutin

destroys response subunit

ventricals out

direction that brain develops

distributive model

each cell detects all tastes and the CNS makes sense of all the input (tells which is strongest)

how do daughter cells know where to migrate

form subplate - helps with migration but doesn't stay there forever next batch of cells form layer 6 5th layer is formed by going through the 6th layer but never the cortical plate

stimulis intensity

frequency is proportional to

non associative learning

habituation sensitization

Protein Kinase A

heterotetrameric enzyme that consists of two regulatory subunits and two catalytic subunits

LTD or LTP depends on

how much ca comes in

Salt- Na has inward current Sour blocks because K is permeable to hydrogen- faster membrane depolarization

how to distinguish salt and sour

perception

how we perceive it

how to tastes help us

identifies dietary components salt- electrolytes sour- protects - can be bad on the gut bitter- toxin detector sweet- energy rich umami - glutamate

G protein coupled receptor**

in resting state, G protein binds to a molecule of GTP when transmitter binds to receptor exposes a binding site for the G protein G protein comes over and binds to receptor GTP phosphorylation (activated for GTP GDP exchange) changing GDP for GTP causes subunit to dissociate which exposes a binding site of adenylyl cyclase produces many molecules of cAMP which is converted to ATP

ageusia

inability to detect taste qualties

anosmia

inability to smell

long term potentiation

induced by synaptic activity homosynaptic -- one synapse

amiloride sensitive Na channel s

insensitive to voltage (concentration drives) like a leak channel, stays open

how are the cortical layers formed

inside out 6 to 5 to 4...

sensory receptors encode

intensity of the stimulus by looking at the frequency

glutamatergic receptors

kainate AMPA -Na NMDA - voltage gated Mg2 clogs groups of metabrotopic glutamate receptors

expression of LTP

long term changes that take place in the synapse AMPA receptor is inserted into postsynaptic cell so nextime glutamate is released there is a higher chance of opening MNDA

pyramidal neuron

looks like a pyramid apical dendrite that goes straight up

where do cranial nerves synapse

low in the brainstem nucleus of solitary tract (glustatoty cortex) goes through the thalamus go upward to cortex (insula-- activated with disgust, primary gustatory) hypothalamus and amygdala

sensitization and purpose

meaningful strong stimulus heightens responses learned fear -- survival

transforms touch

mechanoreceptor

where is explicit memory stored

medial temporal lobe

modifiable synapses are

modifiable in both directions

Eric Kandel

molecular mechanisms that lead to synaptic plasticity what is the physical basis

more Ca signaling same amount of glutamate has a better chance of having Na coming in so there is a higher EPSP

more AMPA receptors results from and causes

nasal

nasal or temporal crosses

guidance cues

neuron goes to corresponding receptors

Hebbian learning rule #1

neurons that fire together wire together when presynaptic neuron is activated at the same time as postsynaptic (from another neuron) then the synapse is strengthened

when os endocannabinoid really important

newborns, puberty

distributed memory storage

no single neuron represents a memory allows for graceful degradation of memories

mossy fiber LTP what mediates

not NMDA PKA* phosphorylates proteins at the snare complex where vesicles dock and more transmitter is released

where are odor molecules detected

odorant receptors in olfactory cilia

first order neuron

sensory neuron that delivers sensations to the CNS

what mediates salt and sour

serotonin

olfacory transduciton

odorants find to ordoratn receptor proteins Golf stimulation activation of adenylyl cyclase formation of camp using ATP opens Ca and Na channels ca activates cl channels (normally causes IPSP but this is EPSP due to the concentration) membrane depolarization (receptor potential)

3 types of cells in the ofacotry epithelium

olfacotry receptor cells supporting cells basal cells

how is horizontal cleft formed

one daughter has all the notch and migrates

classical conditioning

one stimulus (CS) predicts another (US)

omnivore

opportunistic eaters

inferotemporal cortex area IT responds to complex shapes and images

part of brain that responds to faces

transforms light

photoreceptor

sensation

physical component

perferant pathway

pokes holes to become direct or trisynaptic pathway allows for multimodal sensory and spatial info

strong NMDA activation means

post synapse is strengthened

retrograde endocannabinoid signaling

post synaptic tells pre to stop synthesized when there is too much is a lipid so it is not bound by membranes and diffuses into extracellular space Cb1 receptor receptors it - Gprotien - intercellular signaling block ca channel on presynaptic channel - cannot release transmitter contents

9th (glossopharyngeal) cranial nerve

posterior - back of tongue

central olfactory pathways

receptor neurons - olfactory bulbs olfactory axon synapses on second order neurons in the glomerulus second order neurons send axons through olfactory tract

rapidly adapting mechanoreceptor

responds at the beginning and the end of the stimulus

instrumental learning

reward and punishment

how they know what neuron to become

semaphorin 3a-- apical dendrite grows toward dendrite grows away GROWTH CONE filapodia contain chemical sensors that help it know where to go lamelpodia

olfactory epithelium looks like a qtip

sense of smell is dependent on this

flow of sensory info into long term

sensory experience (memory acquisition) -- short term (memory consolidation) -- long term mem

mixed nerves

somatic and visseral carry info from different regions of the body to the CNS

glossopharyngeal (9) different functions

somatic motor - movement of muscles in the throat visceral motor - control of salivary glands special sensory - taste on posterior (back) 1/3 of the tongue visceral sensory - detects blood pressure

basal cells

source of new receptor cells

where is the physical change during habituation

still is an action potential less glutamate is released and receptors maintain sensitivity

ltm in sensitization

synthesis of new proteins alterations in gene expression growth of new synaptic connections

excitatory amino acid transporters

take up glutamate (excitatory amino acid) -- too much leads to too much ca exist on astrocyte, pre, and post only work under normal conditions how endocannabinoid system helps

mechanisms of taste transduction (salt examples)

tastant channel permeable to NA Na diffuses in according to concentration gradient sensitive to amiloride as it is depolarized voltage gated na and ca channels open serotonin is released (5HT)

slowly adapting mechanoreceptor

tells the entire period stimulus is present

transforms thermal

thermal receptors

Ca

what activates taste specific ion channel

NMDA activation

what determines how much ca comes in

G Protein coupled receptor families (GPCRs) type 1 ATP

what mediates sweet, umami

camp cyclic nucleotide gated ion channels

what opens Ca during olfactory

why do the neurons from each eye grow together

when they are neighbors there is correlated activity (left goes to a, right goes to b) patterned spontaneous activity also determined by what the visual field is seeing

pial zone

where DNA replication happens