Limbic System

Question 1

2 sulci of the limbic system

Answer 1

Rhinal - anterior

Collateral - posterior

Question 2

Papez circuitry

Answer 2

Hippocampus to mamillary bodies via fornix…mammillary bodies to anterior nucleus via mammillo-thalamic tract…anterior nucleus to cingulate cortex via anterior limb of IC…Cortex to hippocampal region via fornix

Question 3

Entorhinal cortex
Piriform cortex
Perirhinal cortex

Answer 3

Entorhinal is part of parahippocampal gyrus

Prifirom and perirhinal cortices both relatred to olfaction

Question 4

Orbitofrontal cortex role

Answer 4

Planning, decision mking and reinforcement of affective value

Regulates planning behvaior with sensitivoty to reward/[unishment

Question 5

Cingulate gyrus and the cingulum

Answer 5

Cingulum is route form neocrotex into the hippocampus

Question 6

Hippocampal formation

Answer 6

Key compoennts in long term meoryr consolidation and retention

Question 7

Parts of the hippocampus

Answer 7

Lateral (bodering inferiro orn of the lateral ventricle)…hippocampus

Dentate is in between

Subiculum is most medial

Question 8

Main input to hippocampus from the cortex is from the

Answer 8

Perforant pathway - this comes from the entorhinal cortex

Entorhinal cortex receives cortical information from the cingulum

Question 9

Main input to hippocampus from subcortical areas is the

Answer 9

Fornix

Cell bodies arise from glutaminergic cell bodies in the subiculum

Also carries cholinergic inputs from the septal nuclei to the hippocampus nd dentate gyris

Question 10

Crus
Body
Columns
Hippocampal commissure

Answer 10

Crus - part that enters and exits the hippocampal foramtion
Body - arching midlin
Columns - input to the thalamus/hypthalamus (postcommissural) and septal nuclei (precommisual)

Question 11

Basal nucleus of meynert

Answer 11

Main cholinergic inputs to the hippocampus and neocrotex

Question 12

Septal nuclei

Answer 12

Cholinergic nucleus that helps facilitate memory consolidation

Input from amygdala (via stria terminalis)

Question 13

Working memory
Short term memory
LT memory

Answer 13

Wokring - associated with prefrontal cortex
ST - hippocampal circuits
LT - hippocamapl that receive info from all association cortices

Question 14

Papez circuit type of memory

Answer 14

Explicit or declarative memory

Question 15

Regions affected in ALzheimers

Answer 15

Medial and temporal lobes

As stages progress, becomes worse

Question 16

Neuroimaging in Alz

Answer 16

In mild, atrophy of hippocampus and entorhinal cortex

High amyloid binding and hypometabolisn in the cingulate gyrus, precuneus and prefrontal crotex

Question 17

Olfactory system

Answer 17

Sensory are in the mucosa of the roof of the nasal cavity

Mitral cell axons form olfactory tract

Anterior olfactory nucleus helps modulate

Question 18

Medial and lateral olfactory stria

Answer 18

Medial - modify output from contralateral bulb

Lateral - raminder of output to the parahippocampal gyrus and directly to amygdfala

Question 19

Piriform cortex

Answer 19

Projects directly to the thalamus and responsible for perception and discrimination of odors

Projects to hippocampal formation along with perirhinal to bring memory into pathway

Question 20

Amygdala outputs to subcortcial structures

Answer 20

Stria terminalis to hypothalamus, thalamus and septal nuclei

Ventral amygdalogufal pathway to the basal forebain (ncuelus accumbens, basal of meynert)…these forebrain can go to hippocampus

Question 21

Amygdala output to cortcial structures

Answer 21

Ventral amygdalofugal pathway to cingulate gyrus and orbitofrontal cortex to allow influences on behavior

Also to thalamus

Question 22

Vnetral tegmentral area

Answer 22

Dopaminergic

Input from amygdala

Output to nucleus accumbens and prefrontal cortex

Question 23

Nucleus accumbens

Answer 23

Input from VTA

Output to prefrontal cortex and cingulate gyrus

Question 24

Mesocrotcial pathway

Answer 24

VTA projections directly to prefrontal and orbitofrontal cortex

Role in frontal lobe executive function

Question 25

Too little DA

Answer 25

Negative signs because of too little in the mesocortical pathway

Question 26

Mesolimbic pathway

Answer 26

VTA dopaminergic to limbic like amygdala, nucleus accumbens, hippocampus via amygdalofugal pathway

Increases activation of the limbic system

Also indicrrect because the nucleus accumbens projects to the PFC as a GABAnergic…when stimulated by VTA, it inhibits PFC

Question 27

Too much dopamine

Answer 27

Positive signs due to increased dopamine in the mesolimbic pathway