Chapter 16 The Limbic System and Cerebral Circuits

Question 1

Amygdala

Answer 1

-Participates in emotions
-Coordinates body’s response to stressful or threatening situations
(diencephalaon and midbrain also part of limbic)

Question 2

Hippocampal formation

Answer 2

-Learning and memory (plays essential role in consolidation of explicit memories (facts))
-Limbic association cortex provides major input

Question 3

4 Components of Limbic System

Answer 3

-Limbic association cortex
-Hippocampal formation and fornix (memory)
-Amygdala (emotions)
Ventral striatum (reward)

Question 4

Components of Limbic System

Answer 4

-Cingulate cortex (frontal and parietal lobes)
-Orbitofrontal cortex
-Temporal pole
-Parahippocampal gyrus (temporal lobe)

Question 5

Where does Limbic Association Cortex receive input from?

Answer 5

-Higher order sensory areas in temporal lobe
-Prefrontal association cortex
-Parietal-temporal-occipital association cortex

Question 6

Cingulum

Answer 6

-Tract that connects prefrontal association cortex, orbitofrontal cortex, and the cingulate gyrus with the parahippocampal gyrus, including the entorhinal cortex

Question 7

3 Components of the Hippocampal Formation

Answer 7

-Dentate gyrus
-Hippocampus
-Subiculum

Question 8

Hippocampal Inputs

Answer 8

Cortical regions and amygdala project to the entorhinal cortex, which projects to hippocampal formation

Question 9

Hippocampal Outputs

Answer 9

Directed back to subcortical structures (e.g. anterior thalamic nuclei), via the fornix and cortical areas via the entorhinal cortex

Question 10

Basic Circuit of the Hippocampal Formation

Answer 10

-Parahippocampal gyrus receives info from limbic association cortex
-Hippocampal efferents originate from the hippocampus and the subiculum
-Fornix is the major output tract
(Dentate gyrus contains neurons that only make connections with hippocampal formation)

Question 11

Mesolimbic Dopamine System

Answer 11

-Originates from ventral tegmental area
-Provides dopaminergic innervation to nucleus accumbens, amygdala, and various parts of cortex (especially prefrontal)
-Axons travel in the medial forebrain bundle

Question 12

Ventral Striatum

Answer 12

-Ventromedial caudate nucleus
-Nucleus accumbens
-Ventromedial putamen
(Drugs, nicotine, and ethanol produce an increase in dopamine in several target areas)