Limbic System

Question 1

Cortical structures in the limbic system

-also called the…

Answer 1

also called the "Limbic Lobe"
structures
-septal area
-cingulate gyrus
-parahippocampal gyrus
-hippicampus
related areas
-orbitofrontal cortex
-prefrontal cortex

Question 2

where is the septal area

Answer 2

area surrounding end of rostrum of corpus callosum

Question 3

associated subcortical nuclei of the limbic system

Answer 3

amygdala
hypothalamus
septal nuclei
anterior thalamic group

Question 4

amygdala location

Answer 4

located deep to the uncus

Question 5

septal nuclei location

Answer 5

deep to septal cortical region

near the fornix and anterior comissure

Question 6

nerve fiber pathways in the limbic system

Answer 6

mamillothalamic tract
fornix
stria terminalis
medial forebrain bundle

Question 7

limbic lobe connections

Answer 7

organizes as a complex loop

• mamillary bodies to anterior thalamic group via mamillothalmic tract
• anterior thalamic group to cingulate gyrus
• cingulate gyrus to parahippocalpal gyrus
• parahippocampal gyrus to hippocampus
• hippocampus to mamillary bodies and septal region via the fornix

Question 8

amygdala is connected to the limbic circuit via the….

Answer 8

connections to the septal region and hypothalamus via stria terminalis

Question 9

limbic system afferents

Answer 9

cortex

reticular formation

Question 10

cortex

-projects to what parts of limbic system

Answer 10

all parts of limbic lobe
amygdala
hypothalamus

Question 11

RF

-projects to what parts of limbic system

Answer 11

all parts of limbic lobe
amygdala
hypothalamus

Question 12

efferents

-limbic lobe projects to…

Answer 12

all parts of cortex

hypothalamus and RF

Question 13

limbic lobe projects to cortex by way of…

Answer 13

thalamic gating

Question 14

efferents

-what structures does the amygdala project to….

Answer 14

dorsomedial thalamic nucleus

brainstem RF

Question 15

efferents

-amygdala projects to dorsomedial thalamic nucleus, which projects to _____

Answer 15

dorso medial thalamic nucleus, which in turn projects to prefrontal cortex (medial forebrain bundle)

Question 16

efferents

-how does the amygdala project to the brainstem RF

Answer 16

both directly an indirectly via the hypothalamus (medial forebrain bundle)

Question 17

limbic system function

Answer 17

generates behaviors necessary for preservation of the individual and the species (motivation, emotion, learning, and memory)

Question 18

limbic system has very powerful effect on which systems

Answer 18

hypothalamus

ANS

Question 19

lesions of the hippocampus and amygdala must be _____ to result in major deficits of normal behavior

Answer 19

bilateral

Question 20

_____ stimulation of the limbic system may result in abnormal behavior

Answer 20

unilateral

Question 21

limbic system has been labeled the _____ system

-what do these stand for?

Answer 21

3-F, 1-R system

• fighting
• fleeing
• feeding
• sexual behavior

Question 22

hippocampus

-functions

Answer 22

attention
memory
spatial orientation
stress

Question 23

hippocampus: attention
- what type of stimulation produces alertness and searching behavior?
- alertness runs through what other circuitry

Answer 23

unilateral or bilateral stimulation

alertness and awareness are cycled through the RF as the reticular activating system

Question 24

hippocampus: memory

- bilateral lesion results in…

Answer 24

results in loss of recent memory and inability to form new memories

Question 25

hippocampus: memory system | - involved in...

Answer 25

formation of declarative (explicit; memory of facts) memories, not procedural (implicit; motor memory) memory

Question 26

hippocampus: memory | - what is the process of consolidation

Answer 26

transfer of short-term memories into lasting memories

Question 27

hippocampus: spacial orientation | - hippocampus has a _____, which makes what possible

Answer 27

cognitive mapping system | makes it possible for us to compare present spatial situation with those already experienced

Question 28

hippocampus: stress | - projections go to...

Answer 28

anterior hypothalamus

Question 29

hippocampus: stress pathway - stress causes this pathway to... - what is the result of this?

Answer 29

``` release CRF (corticotropin releasing factor) this then acts at the pituitary to release ACTH (adrenocorticotropic hormone) ```

Question 30

hippocampus: stress pathway | - ACTH function

Answer 30

acts on the adrenal glands to secrete cortisol and vasopressin

Question 31

hippocampus: stress pathway - what type of stress is this - what type of stress is this not

Answer 31

the stress the body senses when there is an injury, not stress related to fear or neuroscience

Question 32

stress related to fear releases _____ from _____ and results in _____

Answer 32

releases norepinephrine from adrenal medulla and increases sympathetic output

Question 33

septal nuclei | -responsible for...

Answer 33

pleasure | rage

Question 34

septal nuclei: pleasure | -stimulation of septal nuclei and _____ can result in...

Answer 34

surrounding hypothalamus (parts of the anterior division) can result in sexual arousal; pleasure/euphoria from drug activation

Question 35

septal nuclei: rage | -bilateral lesions of the septal region result in...

Answer 35

hyperexcitability (exaggerated jumping when startled) | rage (unprovoked attacks)

Question 36

amygdala functions

Answer 36

sensory-affective interactions emotion modulator or controller of hypothalamic activities

Question 37

amygdala: sensory-affective interactions - explain this role - lesions produce...

Answer 37

amygdala is important for instinctive reactions to sensory stimuli, including the motivational and emotional significance of sensations lesions produce inappropriate emotional responses to sensory stimuli

Question 38

amygdala: emotion - emotional component of... - important for...

Answer 38

emotional component of learning important for developing emotional reactions to new experiences, which, if repeated, become instinctive emotional reactions.

Question 39

amygdala: emotion nuclei | - implicated in...

Answer 39

learned memory of fear

Question 40

amygdala: modulator or controller of hypothalamic activities | - stimulation or lesion of the amygdala can produce...

Answer 40

autonomic effects, arousal, sexual activity, motor activity related to eating, aggressive behavior

Question 41

amygdala: modulator or controller of hypothalamic activities | - functional locations within the amygdala

Answer 41

lateral amygdala | medial amygdala

Question 42

lateral amygdala - stimulation produces... - based on the...

Answer 42

produces -a gradual build up of aggressive behavior (anger) -hyperphagia (overeating - lateral hypothalamus) -pleasure reactions -tameness based on the normal social behaviors of an individual

Question 43

medial amygdala | -stimulation produces...

Answer 43

decreased aggressive behavior aphagia (medial hypothalamus) decreased sadness decreased fear-associated defensive behavior

Question 44

limbic system interaction with hypo | -generally throught to be displayed as...

Answer 44

autonomic component of aggressive or defensive behaviors

Question 45

limbic system interaction with hypo | -medial limbic of amygdala to medial hypo are more attuned to what behaviors?

Answer 45

behaviors generated out of defense of self

Question 46

limbic system interaction with hypo: lateral limbic parts of amygdala - receive _____ from _____ - connected more with... - region is associated with _____ behaviors

Answer 46

receive powerful sensory association cortical input connected more with lateral divisions of the hypo more associated with predatory or feeding behaviors

Question 47

anterior septal region - more attuned to acting in _____ - this region is thought to function in the _____

Answer 47

acting in satisfaction or pleasure | this region is thought to function in the euphoria associated with the onset of addictions: cocaine, methamphetamines