Neuromodulators

Question 1

Neuromodulators are a set of specific _______ synthesized and released by a specific set of neural _____

Answer 1

neurotransmitters; pathways

Question 2

Common neuromodulator transmitters include

Answer 2

Dopamine
Norepinephrine
Epinephrine
Serotonin
Histamine
Acetylcholine

Question 3

Neuromodulator pathways: each neuromodulator transmitter is synthesized by several small clusters of _____. Most of these clusters are located in the _____. Axons of these neurons project diffusely throughout the brain and ______.

Answer 3

Neurons
brainstem
spinal cord

Question 4

What is a neuromodulator pathway?

Answer 4

nuclei (groups of neurons) that synthesize neuromodulators

Question 5

Where are the neurons that synthesize dopamine located? (2)

Answer 5

1. Substantia Nigra

2. Ventral tegmental area (VTA)

Question 6

Where are the neurons that synthesize norepinephrine located? (1)

Answer 6

the Locus ceruleus

Question 7

Where are the neurons that synthesize serotonin found? (1)

Answer 7

the Raphe nuclei

Question 8

A scary experience that triggers norepinephrine would activate which neuromodulator pathways?

Answer 8

locus ceruleus

Question 9

Serotonin is related to sleeping, eating, digesting and overall feelings of well-being and happiness. What neuromodulator pathway is serotonin synthesis found in?

Answer 9

the Raphe nuclei

Question 10

Dopamine plays a major role in precision of movements (motor function) as well as pleasure, euphoria, compulsion, preservation, reward and addiction. What neuromodulator pathways are dopamine synthesis found in?

Answer 10

1. Substantia Nigra

2. VTA (ventral tegmental area)

Question 11

Acetylcholine has a major function in the parasympathetic nervous system, such as contracting smooth muscle, dilating blood vessels and slowing the heart rate. What neuromodulator pathway is acetylcholine synthesis found in?

Answer 11

Basal forebrain

Question 12

Where are the neurons that synthesize acetylcholine found? (1)

Answer 12

Basal forebrain

Question 13

Neurons that synthesize acetylcholine act at the muscarinic ____tropic receptors

Answer 13

metabotropic

Question 14

Neuromodulators operate almost exclusively through which type of receptors?

Answer 14

G-protein coupled metabotropic receptors

Question 15

Neuromodulators alter the electrical excitability of many other neural pathways and systems involved in ____, _____ and _____ functions.

Answer 15

sensory
motor
cognitive

Question 16

Neuromodulator neurons have ____-like properties and fire regular trains of AP due to __trinsic membrane properties

Answer 16

pacemaker

intrinsic

Question 17

Regular, intrinsic firing patterns of neurons located in the locus coeruleus synthesize which neurotransmitter?

Answer 17

norepinephrine

Question 18

The firing rate of neuromodulator neurons is further modulated by _____ state

Answer 18

behavioral

Question 19

Additional changes in firing rate of neuromodulator neurons may be either ___ (steady) or ___ (brief, time-locked to behavioral events)

Answer 19

tonic

phasic

Question 20

Behavioral states associated w/ change in the level of activity in neuromodulator systems include _____ (reward), _____ (arousal) and __/__ (consciousness)

Answer 20

motivation
attention
sleep/wake

Question 21

There is a ____ firing rate of noradrenergic neurons in the locus ceruleus associated with waking, conscious state

Answer 21

higher

Question 22

_____ axons have very specific projections, contacting very few postsynaptic neurons

Answer 22

glutamatergic

Question 23

____ axons have diffuse projections, contacting MANY postsynaptic neurons

Answer 23

neuromodulator

Question 24

___ numbers of neurons synthesize and release neuromodulators, yet, have a ___ influence on behavior

Answer 24

few; large

Question 25

Varicosities of neuromodulator axons are described as

Answer 25

beads on a string

Question 26

There is a global, ____ release of neuromodulators as the action potential travels down the axon and releases neuromodulators from each ____

Answer 26

diffuse; varicosity

Question 27

___ neuromodulator receptors influence cortical pyramidal neurons.

Answer 27

multiple

Question 28

Different receptors act through different ___ proteins

Answer 28

G

Question 29

There are both ____ and ____ effects on ion channels. The net effect on the neuron depends on which neuromodulator receptors are expressed and the patter of activity in the ______

Answer 29

convergent; divergent | neuromodulator pathways

Question 30

The dopamine system is implicated in which 3 main clinical applications?

Answer 30

1. Parkinson's 2. Addiction 3. Schizophrenia

Question 31

Serotonin and norepinephrine (noradrenaline) systems are implicated in which main clinical application?

Answer 31

depression

Question 32

Loss of the ascending neuromodulator function can contribute to what major issue?

Answer 32

coma

Question 33

Histamine is synthesized in the ______ nucleus of the _____

Answer 33

tuberomammillary; hypothalamus

Question 34

If you began to experience anaphylactic shock from a bee sting, your body would release a ton of histamine to combat the invading toxin. Where would the neuromodulator pathway of histamine be activated?

Answer 34

the tuberomammillary nucleus of the hypothalamus

Question 35

_____ pathways are dysregulated in schizophrenia and addiction, and originate from the _____

Answer 35

dopamine; VTA

Question 36

____ neurons die in Parkinson's disease, and originate from the ____

Answer 36

dopamine; substantia nigra

Question 37

Axons of which brain system target widespread regions in the brain and spinal cord?

Answer 37

locus coeruleus

Question 38

The main catecholamines in the brain are ____ and ____

Answer 38

dopamine; norepinephrine

Question 39

Tyrosine hydroxylase converts tyrosine into ______, which crosses the ____ and is a treatment for Parkinson's.

Answer 39

L-DOPA; BBB

Question 40

Dopa decarboxylase converts _____ into ____ which does NOT cross the BBB.

Answer 40

L-DOPA; dopamine

Question 41

Dopamine b-hydroxylase converts ____ into _____ via one additional step

Answer 41

dopamine; norepinephrine

Question 42

The primary mechanism of DA/NE is _____

Answer 42

uptake

Question 43

The secondary mechanism of DA/NE is ____

Answer 43

enzymatic degradation

Question 44

D1 ____ cAMP whereas D2 ____ cAMP

Answer 44

stimulates; inhibits

Question 45

For DE receptors, cAMP binds to regulatory subunits on which protein?

Answer 45

Protein Kinase A (PKA)

Question 46

For NE receptors, b receptors ___ production of cAMP wherease a2 receptors ____ production of cAMP

Answer 46

increase; decrease

Question 47

Dopamine neurons are ____ when a monkey gets an unexpected reward OR sees a stimulus it has learned to predict rewards for

Answer 47

excited

Question 48

Dopamine neurons are ____ when a monkey expects a reward but doesn't get it

Answer 48

inhibited

Question 49

Reward (prediction error) signal is involved in behavioral reinforcement, ____ and _____

Answer 49

learning | addiction

Question 50

Norepinephrine neurons have a ___ baseline firing rate when the monkey is drowsy

Answer 50

low

Question 51

NE neurons have a ___ baseline rate with phasic responses to stimuli when paying attention and ___ in a task

Answer 51

low; engaged

Question 52

NE neurons have ___ baseline activity without phasic responses when there are alter and ____ tasks

Answer 52

high; switching

Question 53

Neural activity of NE reflects _____ and _____

Answer 53

attention; arousal

Question 54

All addictive drugs ____ the DA levels in part of the reward system called the nucleus _____

Answer 54

increase; accumbens

Question 55

Psychostimulants such as _____ and ______ cause an overall ____ in DA levels

Answer 55

cocaine; amphetamines; increase

Question 56

Cocaine ____ dopamine transporter (DAT) on the __synaptic DA terminals responsible for synaptic uptake of DA.

Answer 56

blocks; pre

Question 57

Amphetamine ____ DA from the synaptic vesicles which ___ through DAT back into the synapse.

Answer 57

releases; leaks

Question 58

Opiates inhibit ______ interneurons in the ____, which suppresses activity of the ____ neurons and increases the firing rate of VTA DA neurons

Answer 58

GABAergic; VTA; GABAergic

Question 59

_____ influence PREsynaptic terminals to increase DA synaptic concentrations in the nucleus _____

Answer 59

psychostimulants; accumbens

Question 60

_____ increase the firing rate of DA neurons in the VTA, ___ing synaptic DA concentrations in the nucleus accumbens

Answer 60

Opiates; increasing

Question 61

Dopamine release is _____ in schizophrenia (SZ) patients

Answer 61

elevated

Question 62

Drugs that elevate ___ levels, such as amphetamines, can cause psychosis. This is why in SZ, even drug-naive patients experience hallucinations.

Answer 62

dopamine

Question 63

Genetic linkage studies implicate mutations in genes related to DA neurotransmission in _______

Answer 63

schizophrenia

Question 64

The clinical efficacy of antipsychotic medications is tightly correlated w/ their ability to bind to which receptors?

Answer 64

D2

Question 65

Serotonin (5-HT) is synthesized by cell bodies in the _____, and different cortical regions express different 5-HT receptor _____

Answer 65

Raphe nuclei; subtypes

Question 66

In Depression, there is altered brain activity in the ____ and ____ areas of the brain

Answer 66

limbic; prefrontal

Question 67

In Depression, there can be changes in the brain's ____

Answer 67

volume

Question 68

Antidepressants ___ synaptic concentrations of monoamines ____ and ____

Answer 68

increase; serotonin; norepinephrine

Question 69

SSRIs are selective serotonin reuptake inhibitors, meaning they ____ uptake

Answer 69

block

Question 70

MAOIs are monoamine oxidase inhibitors, meaning they ____ degradation

Answer 70

block

Question 71

Drugs that INCREASE synaptic concentrations of 5-HT will subsequently

Answer 71

elevate mood