Norden - Reticular Formation

Question 1

Where is the nucleus basalis of Meynert?

Answer 1

Basal forebrain

Question 2

The nucleus basalis of Meynert has neurons which use acetylcholine as the neurotransmitter. These project widely to the cerebral cortex ______ a synapse in the thalamus

Answer 2

Without

Question 3

Works to gate thalamo-cortical relay neurons so that all sensory input gets to the cortex at the same time.
Only has connections with other nuclei in the thalamus
Receives input from other thalamic nuclei and gets widespread information from the cortex

Answer 3

Reticular nucleus of the Thalamus

Question 4

Part of reticular formation in the midbrain that plays a role in determining whether pain info will be transmitted to higher centers of the brain

Answer 4

Periaqueductal gray

Question 5

5HT / serotonergic neurons that have widespread projections to the frontal lobe including cortex w/o relay in thalamus. Plays role in regulation of consciousness, mood, and attention.

Answer 5

Dorsal Raphe Nuclei

In midbrain

Question 6

Pigmented neurons that use epinephrine.

Has widespread projection to; limbic structures, cortex w/o thalamic relay, dorsal horn of spinal cord

Plays role in; arousal, response to stress, mood, pain modulation, selective attention

Answer 6

Nucleus locus coeruleus

(In pons

Question 7

Two nuclei.
Cholinergic
Involved in wakefullness, REM sleep, and indirect arousal system.
Must be suppressed in order for sleep to occur

Answer 7

Pedunculo-pontine nucleus

Laterodorsal tegmental nucleus

Question 8

Abnormalities in the maturation of spines of respiratory center neurons are seen in the reticular formation in?

Answer 8

Infants who have died from SIDS

Question 9

Two nuclei, both with descending projections to lamina of rexed II (substantia gelatinosa).

Help modulate the transmission of pain in the nervous system

Answer 9

Nucleus raphe magnus

Rostral ventral medulla area

Question 10

Rostral ventral medulla area (RVM) neurotransmitter

Answer 10

Glutamate

Question 11

Nucleus raphe magnus Neurotransmitter

Answer 11

Serotonin 5 HT

Question 12

The reticular formation nuclei play a role in the maintenance of __?

Answer 12

Consciousness
Wakefullnes
Arousal
Attention

Question 13

Activated exclusively during the waking state

Answer 13

Nucleus locus coeruleus, raphe nucleus of ret. form. And tuberomammillary nuclei

Question 14

Indirect system, activated during the waking state and during REM sleep

Answer 14

Pedunculo-pontine and laterodorsal tegmental nuclei

Question 15

The projections of ARAS function to _____ cortex to allow for incoming sensory info to be processed

Answer 15

Prime

Question 16

You are not conscious or aware unless

Answer 16

Your reticular formation stimulates your cortex

Question 17

The ARAS is believed to be responsible for shunting of potentially life-threatening or fearful info directly to the ____ from the _____

Answer 17

Amygdala

Thalamus

Question 18

The ARAS performs _____ gating of information

Answer 18

Bottom up

Question 19

The cortex can exert _____ gating of information

Answer 19

Top down

Question 20

For normal consciousness / wakefullness, both the ++++ and the ____- must be activated

Answer 20

ARAS and cortex

Question 21

A prolonged an profound loss of consciousness and responsiveness.
Both wakefulness/ arousal and awareness are lost.
Sleep/wake cycles absent
Brainstem reflexes may be elicited, but no visual tracking.
Unarousable and unresponsive

Answer 21

COMA

Question 22

Consists of :
Periods of responsiveness/ wakefullness
Minimal/variable awareness
Sleep wake cycles are present
Highly variable EEG
Visual tracking occurs

Answer 22

Minimally conscious state

Question 23

Consists of :
NO visual tracking
NO awareness
Variable periods of wakefulness and arousal
Sleep / wake - variable but intact
Brainstem function intact
May be aroused to noxious stimuli

Answer 23

Vegetative state

Question 24

A persistent vegetative state is when a vegetative state lasts_ _- _

Answer 24

1 month

Question 25

Causes of COMA

Answer 25

Bilateral lesion of the brainstem (specifically ARAS at the ponto-mesencephalic - diencephalic junction) Bilateral lesion of the hemisphere leading to compromise (most commonly from encephalopathy due to anoxic, toxic, or metabolic insult; increased ICP; overdose Bilateral lesion of the thalamus

Question 26

Irreversible unconsciousness w/ complete loss of brain function, including irreversible loss of the ability to breath

Answer 26

Brain death

Question 27

Major transmitters used in the reticular formation:

Answer 27

Dopamine Serotonin Norepinephrine

Question 28

Reticular formation projections modulate the activity of ____ and ____

Answer 28

Glutamate and GABA

Question 29

What are the 4 dopaminergic pathways in the brain?

Answer 29

Substantia nigra —> neostriatum. [extrapyramidal motor system] Ventral Tegmental area (VTA) —> nucleus accumbens septi [reward system] VTA —> cortex ( especially prefrontal areas ) Arcuate nucleus (of tuberal region of hypothalamus —> anterior pituitary [inhibition of the synthesis and release of prolactin]

Question 30

Positive signs and symptoms of schizophrenia (hallucinations, delusions, psychosis) are due to?

Answer 30

Too much dopamine in meso-limbic circuits

Question 31

Negative signs and symptoms of schizophrenia (cognitive dysfunction, difficulty concentrating, difficulty w/ memory) are due to ?

Answer 31

Too little dopamine in meso-cortical circuits

Question 32

Why does haldol exacerbate the negative s/s of schizophrenia?

Answer 32

Haldol blocks the dopamine in the meso-limbic circuit, effectively stopping the positive symptoms. It also blocks the already too little dopamine in the meso-cortical circuit, exacerbating the negative s/s.

Question 33

Tardive dyskinesia is caused by?

Answer 33

Hypersensitization of the dopamine receptors in the extrapyramidal motor system, secondary to haloperidol usage.

Question 34

Uncontrolled movement, especially of the upper limbs and face

Answer 34

Tardive dyskinesia

Question 35

The ______, located in the pontine reticular formation provides the majority of norepinephrine input in the nucleus

Answer 35

Nucleus locus coeruleus

Question 36

5HT/serotonin is a major neurotransmitter used in

Answer 36

Raphe nuclie

Question 37

Dorsal raphe nucleus has a critical role in the modulation of

Answer 37

Mood

Question 38

This nucleus in the medullary reticular formation receives input from the periaqueductal gray and sends to the substantia gelatinosa in the spinal cord to modulate pain

Answer 38

Nucleus raphe magnus

Question 39

Sends acetylcholine to the cortex w/o relay in thalamus. Has role in human behavior

Answer 39

Nucleus basalis of meynert

Question 40

What physical changes can be seen in adults whom were abused (sexual, neglect, emotional) as children

Answer 40

- decreased limbic structure volume (left greater than right ) - cerebral cortex (prefrontal and temporal) - hippocampus and dentate nucleus (these people have decreased scores on verbal memory tests) - amygdala - cerebellar vermis - corpus callosum

Question 41

What areas see increased activation in adults who were abused as children?

Answer 41

Amygdala HPA axis ARAS - hyperalertness and arousability

Question 42

The greatest effect of abuse from males comes from childhood experiences of ?

Answer 42

Neglect

Question 43

The greatest effect of abuse from females comes from childhood experiences of ?

Answer 43

Sexual abuse (from family member especially)

Question 44

Altered protein subunits of GABA receptors in the amygdala secondary to childhood abuse can cause?

Answer 44

Decreased inhibitory circuits —> hyperactivation