Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

NEUR532 > Limbic System > Flashcards

Limbic System Flashcards

1
Q

what does the limbic system do?

A

-Brings together components of the cerebral hemispheres and the diencephalon

-The limbic system is concerned with memory and with visceral and motor responses involved in defensive and reproductive behaviours

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

describe the limbic lobe

A

-Ring of grey matter on the medial aspect of the each hemisphere
–Parahippocampal and cingulate gyri
–Septal area

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What does the limbic system include?

A

-Limbic lobe
–Hippocampus
–Dentate gyrus
–Amygdaloid body
–Hypothalamus
–Anterior thalamus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

how does the hippocampus develop? and what does it come to occupy?

A

-by a process of continuing the expansion of the medial edge of the temporal lobe
-comes to occupy the floor of the temporal horn of the lateral ventricle
-In the mature brain the parahippocampal gyrus on the external surface is continuous with the concealed hippocampus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the alveus of the hippocampus

A

-layer of white matter on the ventricular surface
–Forms the fimbria
–Continues to the crux of the fornix

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

describe the surface of the dentate gyrus of the hippocampus

A

-surface is toothed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

describe the subiculum of the hippocampus

A

Transition from 3 layered hippocampus to the six layered parahippocampus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what are the 3 main areas of the hippocampus?

A

-CA1 (cornu ammonis)
-CA1 is adjacent to the subiculum

-CA2

-CA3
-CA3 is near the dentate gyrus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the 3 layers of the hippocampal cortex?

A

-pyramidal cell layer (stratum pyamidale)
-molecular layer
-polymorphic layer (stratum oriens)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

describe the pyramidal layer of the hippocampus

A

-Large pyramidal neurons
-Principle cells of the hippocampus
-Dendrites extend into the molecular layer
-Axons traverse the alveus and fimbria
-Branches are called the schaffer collaterals pass through the polymorphic layer
-Synapse with dendrites of other pyramidal cells in the molecular layer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

describe the molecular layer of the hippocampus

A

-Interacting dendrites and axons

-Located in the centre of the hippocampus surrounding the hippocampal sulcus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

describe the polymorphic layer of the hippocampus

A

-Similar to layer 6 of neocortex
-Located beneath the alveus and contains axons, dendrites and interneurons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what are the 3 layers of the dentate gyrus

A

-granule cell layer
-mossy fibres
-hilus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Describe the granule cell layer of the dentate gyrus

A

-Small neurons
-principle cells of the dentate gyrus
-Region of adult neurogenesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

describe the mossy fibres of the dentate gyrus

A

-Efferent fibres of the dentate gyrus
-Many branches that synapse with the principle cells in CA3 and CA2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

describe the hilus layer of the dentate gyrus

A

-Contains the axons of the granule cells and interneurons

17
Q

what are the main afferent connections of the hippocampus

A

-Cerebral cortex
-Septal area
-Contralateral hippocampus
-Various brainstem nuclei

18
Q

describe the cortical afferent connections of the hippocampus

A

-Largest contingent of fibres is from the entorhinal cortex
-Follow two routes to the hippocampus

19
Q

describe the perforant path

A

-From entorhinal cortex through the subiculum across the hippocampal sulcus to the dentate gyrus

20
Q

describe the alvear path

A

-Traverses the subcortical white matter to end in the hippocampus

21
Q

Describe the entorhinal cortex

A

-Part of the primary olfactory area
-Also receives association fibres from the neocortex of the temporal lobe
-Which in turn communicates with various sensory regions of neocortex
-Through these connections via the perforant and alvear paths the hippocampal formation is informed of all sensory information as well as higher brain functions

22
Q

describe the connections of the contralateral hippocampus

A

-commissural fibres cross the midline at the hippocampal commissure

23
Q

describe the septal area afferents

A

-Septal and basal forebrain cholinergic nuclei via the fimbria-fornix (cholinergic and GABAergic)

24
Q

describe the afferent connections from brainstem to hippocampus

A

-Ventral tegmental area (dopamine)
-Locus coeruleus (noradrenalin)
-Raphe nuclei (serotonin)

25
describe the efferent connections of the hippocampus
-Connections through which the hippocampal formation receives information from the entorhinal area and neocortex are paralleled by reciprocal connections -Descending projections to diencephalon and brainstem via the fimbria-fornix
26
describe the fornix
-Contains around 1 million myelinated axons -Most from the subiculum rest from hippocampus or afferents to the hippocampal formation -Efferent fibres first traverse the alveus on the way to the fimbria -Fimbria continues to the crus of the fornix -The crus curves around the thalamus and joins to form the body of the fornix -Above the third ventricle the body of the fornix separates into the columns -Columns innervate the septal area anterior hypothalamus substantia innominata, lateral dorsal thalamus and the mammillary bodies
27
what are the afferents to the circuit of papez
-Neocortex -Thalamus -Septal area -Reticular formation: –Raphe nuclei –Ventral tegmental area –Catacholamine nuclei
28
what are the efferents from the circuit of papez
-Neocortex -Reticular formation: – Raphe nuclei – Ventral tegmental area – Catacholamine nuclei -Brainstem/spinal cord: – Solitary nucleus – Dorsal nucleus of the vagal nerve – Autonomic nuclei of the spinal cord
29
what is the circuit of papez?
going downwards is the circuit -Entorhinal cortex area of the parahippocampal gyrus -VIA Perforant and alvear pathway -Hippocampal formation -VIA Fimbria-fornix -Mammilary body -VIA Mammilothalamic fasciculus - Anterior thalamic nuclei -VIA Internal capsule -Cingulate gyrus -VIA Cingulum -Entorhinal cortex
30
what is the circuit of papez for?
Ring of interconnected nuclei involved in emotion and emotional expression
31
describe the amygdaloid body
-Several nuclei situated between the anterior end of the temporal horn of the lateral ventricle and the ventral surface of the lentiform nucleus -Corticomedial group: –Dorsomedial division of the amygdaloid body, blends in with the cortex of the uncus –Afferent fibres come from the olfactory bulb - Ventrolateral division: – Basolateral – Central: * No input from olfactory bulb * Connect with the corticomedial group and entorhinal cortex * Included in the limbic system
32
what are the reciprocal connections with cortex from basolateral amygdala
-Frontal –Temporal –Cingulate gyrus
33
what are the subcortical connections of basolateral amygdala
– Thalamus – intralaminar nuclei – Catecholamine nuclei – Raphe nuclei – serotonin – Parabrachial nuclei – substance P – Ventral tegmental area - dopamine – Basal forebrain nuclei – acetylcholine
34
what are the afferents of central nuclei of amygdala
-Receives afferents from the corticomedial and basolateral nuclei
35
what are the reciprocal connections with cortex of central nuclei of amygdala
– Prefrontal – Temporal – Anterior cingulate gyrus
36
what are the efferent connections of central nuclei of amygdala
-Septal area, preoptic area, anterior hypothalamus – Via the stria terminalis - Vagus nerve and the solitary nucleus – Via the medial forebrain bundle - Nucleus accumbens and the dorsomedial nucleus of the thalamus –Via the ventral amygdalofugal pathway
37
describe the habenular nuclei connections
-Habenular nuclei –Via the stria medullaris thalami -Habenula innervates the interpeduncular nucleus –Via the habenulointerpeduncular tract -Habenular nuclei also receive afferents from globus pallidus providing a pathway by which the neocortex can influence autonomic function
38
What are the functions of the amygdaloid body?
-Central and basolateral nuclei are chiefly responsible for the behavioural and emotional functions of the limbic system -Emotion – activities of the brain evoked by incentives for survival -strong affective reactions such as: –Fear and anger –Sexual behaviour -Electrical stimulation of the amygdala: –Increased heart rate and respiration –Suppression of salivation –Pupillary dilation –Changes in facial expression -Therefore, the amygdala may give rise to the automatic and somatic accompaniments of fear and anxiety

NEUR532 (14 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions