Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

YR2: Neuroscience and Mental Health > Olfaction and the Limbic System > Flashcards

Olfaction and the Limbic System Flashcards

1
Q

What the 3 types of cell that makes up the olfactory epithelium?

A

Bipolar Olfactory Neurones
Sustentacular Cells: support cells mainly providing metabolic support
Basal Cells: for regeneration in olfactory neurones

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

Where is the olfactory bulb found?

A

Sitting on top of the cribriform plate

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

Which cells synapse within the olfactory bulb?

A

Bipolar cells pass their axons through the cribriform plate to synapse with 2nd order neurones (olfactory bulb mitral cells) in the glomeruli within the olfactory bulb

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

What structure do the 2nd order neurones form and what does this structure split into?

A

Olfactory tract

It splits to form the medial + lateral olfactory stria

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

Where does higher processing of smell take place?

A

Piriform Cortex

Orbitofrontal Cortex

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

What is a clinical deficit in the olfactory system called?

A

Anosmia

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

What is a common cause of anosmia?

A

Mid-face trauma
Impact with enough force could cause a fracture of the cribriform plate, shearing the neurones going from the olfactory epithelium to the olfactory bulb

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

The piriform cortex is found within the temporal lobe. Explain the significance of this with regards to epileptic patients.

A

Epilepsy is often focused in the temporal lobe
Some people experience PRODROMAL AURA (they are aware of an imminent seizure because they’ll get a distinct smell beforehand)

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

Neurodegenerative disease is a relatively common cause of anosmia. State 2 neurodegenerative diseases that could cause anosmia.

A

Alzheimer’s disease

Parkinson’s disease

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

What is the limbic system?

A

A rim of cortex adjacent to the corpus callosum + diencephalon
Structurally + functionally interrelated areas considered as a single functional complex

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

What are 4 roles of the limbic system?

A

Processes aimed at survival of individual:
Homeostasis (hypothalamic functions e.g. reg. of food intake + pituitary hormone release)
Agonistic behaviour (fight or flight)
Sexual + reproductive behaviour
Memory

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

State 2 important parts of the limbic system that are found within the temporal lobes.

A

Hippocampus

Amygdala

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

What circuit are the Hippocampus + Amygdala part of?

A

Papez Circuit

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

What is the cortical representation of the limbic system?

A

Cingulate Cortex

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

What is the function of the Papez circuit?

A

It is a neural circuit for the control of emotional expression

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

Describe/draw the papez circuit.

A

Hippocampus –> (Fornix) –> Mammillary Bodies of Hypothalamus –> (Mammillo-Thalamic Tract (MTT)) –> Anterior Nucleus of the Thalamus –> Cingulate Cortex –> (Cingulum Bundle) –> Hippocampus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is our emotional expression ‘coloured’ by?

A

Neocortex

18
Q

What form of imaging is used to study the limbic system?

A

Digital Tensor Imaging: shows co-instant activity in different parts of the brain thus showing which parts of the brain are working together

19
Q

Describe the afferent pathway of the hippocampus.

A

Afferent Pathway = Perforant Pathway
Entorhinal cortex is linked to the hippocampus via the perforant pathway
Entorhinal cortex receives input from all other parts of the neocortex

20
Q

What is the efferent pathway of the hippocampus called?

A

Fornix

Fimbria when still attached hippocampus

21
Q

What are the functions of the hippocampus?

A

Memory

Learning

22
Q

What happens to the hippocampus in Alzheimer’s disease?

A

It shrinks severely

23
Q

Describe the spatial relations of the hippocampus and the fornix to other important brain structures.

A

Hippocampus lies on the floor of the lateral ventricles
Fornix comes out of the hippocampus + passes under the corpus callosum
It then dives inferior + anteriorly towards the mammillary bodies

24
Q

Describe the appearance of advanced Alzheimer’s disease on a CT head scan in the coronal plane.

A

Extensive cortical atrophy
Ventricles enlarged
Widening of sulci

25
Q

State 2 microscopic hallmarks of neurodegeneration.

A

Tau Immunostaining
Intracellular pathology: cytoskeleton has been compromised
Tau proteins staining highlights the damaged neurones
Senile Plaques
Extracellular pathology
Lumps of protein sitting in between cells in the neuropil

26
Q

Describe the anatomical progression of Alzheimer’s disease, including the symptoms experienced.

A 
Early 
Hippocampus + entorhinal cortex effects 
Short-term memory problems 
Moderate 
Parietal lobe (where you have your procedural memory)
Effects: dressing apraxia 
Late  
Frontal lobe 
Loss of executive skills + personality change
27
Q

Where is the amydala found?

A

In the white matter of anterior temporal lobe

28
Q

What are the afferent connections of the amygdala?

A 
Olfactory Cortex 
Septum (septal nuclei) 
Temporal Neocortex 
Hippocampus  
Brainstem
29
Q

What is the main output pathway of the amygdala?

A

Stria terminalis

30
Q

What is the function of the amygdala?

A

Fear + Anxiety

Fight or flight

31
Q

In Alzheimer’s and Parkinson’s disease, the amygdala starts showing pathology early on. What are the possible outcomes of this?

A

Patients could either become terrified of everything or they could become totally disinhibited + become quite aggressive

32
Q

State and describe a syndrome affecting the amygdala.

A 
Kluver-Bucy Syndrome  
Bilateral lesions of the anterior temporal lobe (including amygdaloid nucleus) 
Symptoms:
Hyperorality
Hypersexuality
Loss of Fear 
Visual Agnosia
33
Q

State 3 structures associated with aggression + the neurotransmitter involved

A

Hypothalamus
Brainstem (periaqueductal grey matter)
Amygdala
5-HT (Serotonin)

34
Q

What are the main afferent connections of the septum?

A

Amygdala
Olfactory Tract
Hippocampus
Brainstem

35
Q

What are the functions of the septum?

A

Reinforcement

Reward

36
Q

Name another structure that is important in the reward system.

A

Nucleus Accumbens

37
Q

Describe another dopaminergic pathway other than the nigro-striatal pathway that is affected in PD

A

Mesolimbic pathway

Ventral Tegmental Area (VTA) of the midbrain –> Median Forebrain Bundles –> Cortex + Nucleus Accumbens + Amygdala

38
Q

Name a structure that is important in drug dependence.

A

Nucleus Accumbens

39
Q

What effect do all drugs of abuse have on the nucleus accumbens?

A

Increase DA release in the NA

Stimulate midbrain neurones, promote DA release or inhibit NA re-uptake

40
Q

Where does the neocortex feed into the Papez Ciruit? What influence does it have?

A

Feeds to the Cingulate cortex

Emotional colouring

YR2: Neuroscience and Mental Health (20 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions