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Functional Neuranatomy > Limbic system > Flashcards

Flashcards in Limbic system Deck (28):
1

paleocortex

-oldest "phylogentic" age
-associated with olfaction and contributes to survival behavior

2

archicortex

-the hippocampus
-contributes to behavior through an organism's ability to learn and remember significant events

3

allocortex

-i think refers to the hippocampus and paleocortex
-usually are three-layered

4

mesocortex

-typically 5 layered
-can be peri-allocortex (closer to the allocortex)
-can be pro-isocortex (closer to the isocortex)

5

isocortex

-determined to be phylogenetically "newer"
-6 layers

6

Describe the Papez Limbic circuit

-hippocampus to the mamillary bodies (hypothalamus) via the fornix
-the mamillary bodies to the anterior thalamus via the mammillothalamic tract
-the anterior thalamus to the cingulate cortex via the thalamocortical projections
-the cingulate back to the hippocampal region

7

What are the main problems with Papez's limbic circuit

-the hippocampus is not a main regulator of the hypothalamus
*the hippocampus does provide important contextual information to emotional experience
* the hippocampus only has minor projections to area of the hypothalamus that are actually outside of the mammillary bodies

8

Areas that are damaged in Korsakoff's amnesia that indicates their importance in memory formation

-mammillary bodies and anterior thalamus

9

Kluver-Bucy symptom

-visual agnosia
-hypersexuality
-hyperorality
-emotional blunting/placidity
-willingness to approach previously fearful stimuli

**later studies showed the importance of the amygdala

10

amygadala

-key regulator of the hypothalamus
-is located deep within the temporal lobe

11

the amgydala is essential for conditioned learning of:

-emotions... particularly fear
-

12

the amygdala receives sensory information from the ____ and ____ into its ___ nucleus

-cortex and thalamus
-lateral

13

the output of the amygdala arises mainly from the _____ and targets:

-central nucleus
-hypothalamus and the brainstem

14

amygdala efferents:
periaqueductal gray to _____
lateral and paraventricular hypothalamus to regulate ____

-periaqueductal gray to regulate skeletomotor behaviors
-lateral and perivenricular hypothalamus to regulate autonomic and endocrine responses

15

What did Joseph LeDoux demonstrate about the amygdala ?

-he found that certain sensory stimuli reach the amygdala directly by way of the thalamus before being routed through cortex (low road)
-more processed sensory information arrives from the cortex at a later time (high road)

16

Cognitive behavioral therapy

-ability of cognitive reasoning to correct and reverse maladaptive emotions is the basis for this therapy
-ventromedial and orbital divisions of the prefrontal cortex can suppress emotional expression by inhibiting the amygdala output

17

Describe the paradox of major depressive disorders

-early functional imaging studies showed reduced blood flow in orbitofrontal and cingulate regions. This correlated withb reduced gray matter volume in these regions.

-recent studies show that these areas are actually hyperactive in depression and they are targeted for therapy by deep brain stimulation

18

orbitofrontal cortex

-helps to guide behavior based on past rewards and punishments

19

damage to the oribitofrontal cortex would result in

-associated with blunted or inappropriate emotions
-poor judgement
often due to failure to inhibit maladaptive responses

20

what were often performed on patients with violent mental illnesses to try to calm them down?

-frontal lobotomies and cingulatomies

21

Targeted cingulatomies are still performed in cases of:

-medically intractable obsessive compulsive disorder
-chronic pain syndromes
-refractory depression or bipolar disorder

22

cingulate gyrus

-lies immediately above the corpus collosum
-is visceromotor
-can produce some somatic function and even produce aggressive reactions
-major area involved in conscious perception of pain and other emotions

23

septum

-a telencephalic structure lying beneath the corpus callosum
-inputs: hippocampus and cingulate cortex
-projections: amygdala, hypothalamus, and brainstem
lesions alter aggressive and sexual behaviors

24

nucleus accumbens

-ventral extension of the striatum
-limbic-motor interface
-processes limbic cortical input and provides adaptive motor strategies for motivated behaviors

25

visceral sensory input to the hypothalamus and amygdala arises from

-nucleus of the solitary tract

26

multimodal processed sensory input derives from association cortices to:

-amygdala, hippocampal region, cingulate and prefrontal cortex

27

motor output of the limbic system:
visceral motor

visceral motor output originates from the hypothalamus and amygdala to brainstem autonomic centers

28

somatic motor output of the limbic system

-comes from prefrontal to premotor cortex
-it is relayed through the basal ganglia nucleus accumbens
aka the limbic motor interface