Case 7 anatomy

Question 1

what are the four pairs of nuclei in the cerebellum?

Answer 1

fasitigial, globose, emboliform (em’s body form), dentate

Question 2

where do these cerebellar nuclei receive information from?

Answer 2

• spinal cord
• olives
• vestibular nuclei
• pons
• reticular formation

Question 3

where do efferent fibres from the cerebellar nuclei project to

Answer 3

• reticular and vestibular nuclei of the pons and medulla
• red nucleus of the midbrain
• ventral lateral nucleus of the thalamus

Question 4

what are the subdivisions of the cerebellum?

Answer 4

• vestibulocerebellum (archicerebellum)
• spinocerebellum (paleocerebellum)
• cerebrocerebellum (neocerebellum)

Question 5

what does the vestibulocerebellum consist of?

Answer 5

flocculonodular node and fastigial nucleus

Question 6

what does the spinocerebellum consist of?

Answer 6

vermis, paravermis, globose and emboliform nuclei

Question 7

what does the cerebrocerebellum consist of?

Answer 7

anterior and posterior cerebellar hemispheres and the dentate nucleus

Question 8

what does the superior cerebellar peduncle contain?

Answer 8

• efferent fibres which arise in the dentate nucleus (largest single structure linking the cerebellum to the rest of the brain) and project to the red nucleus, thalamus and cortex
• afferent tectocerebellar fibres and afferent fibres from the anterior spinocerebellar tract

Question 9

what does the middle cerebellar peduncle contain?

Answer 9

afferent fibres from the opposite pontine nucleus

Question 10

what does the inferior cerebellar peduncle contain?

Answer 10

• afferent fibres from the posterior spinocerebellar tract and from the olivocerebellar tracts
• both afferent and efferent fibres which originate or terminate in the vestibular nucleus

Question 11

what are the names for collections of different nuclei in the basal ganglia?

Answer 11

• Corpus striatum = caudate nucleus, putamen and globus pallidus
• Lentiform nucleus = putamen and globus pallidus

Question 12

what is the limbic system involved in?

Answer 12

• memory
• behaviour
• emotion
• olfaction
• The main purpose of the limbic system is in the preservation of the species and in order to achieve this it has to ensure the safety of the individual and the passing on of his/her genes
• It prepares the individual to deal with hostile circumstances by developing the short-term memory and allowing stimulation of its various parts to produce pleasure or aversion
• It affects motivation, controls sexual behaviour and promotes caring of offspring

Question 13

what does the limbic system consist of? where is afferent information received from and where do efferent fibres project to?

Answer 13

• The functioning of the limbic system is complex and not fully understood
• The limbic system consists of a collection of cortical and subcortical neurons and their interconnections
• Afferent information is received from the association cortex and fibres leaving the limbic system project to the hypothalamus

Question 14

where is the limbic lobe? what does it consist of?

Answer 14

• border around the corpus callosum and rostral brain stem (limbic means border)
• consists of cingulate gyrus, parahippocampal gyrus and subcallosal gyrus

Question 15

what does the hippocampal formation consist of?

Answer 15

• hippocampus
• dentate gyrus
• parahippocampal gyrus

Question 16

what does the hippocampal formation play a major part in?

Answer 16

memory, learning and spatial navigation

Question 17

where does the hippocampal formation receive input from?

Answer 17

the entorhinal area of the parahippocampal gyrus

Question 18

where does the hippocampus lie?

Answer 18

along the floor of the inferior horn of the lateral ventricle

Question 19

where is the dentate gyrus?

Answer 19

dentate gyrus extends between the hippocampus on a coronal brain slice; it is a C-shaped structure on the inferomedial aspect of the temporal lobe

Question 20

what is the amygdaloid body involved in?

Answer 20

• formation and storage of memories
• associated with acquisition and expression of fear conditioning
• sense of smell

Question 21

where does the amygdala receive input from?

Answer 21

• association cortices
• cingulate gryrus
• olfactory bulb
• brain stem visceral pathways

Question 22

where is the amygdala?

Answer 22

lies in the temporal lobe close to the uncus, overlying the anterior part of the inferior horn of the lateral ventricle

Question 23

what are the connecting pathways in the limbic system?

Answer 23

number of structures connect the various parts of the limbic system to each other and to the hypothalamus:

• fornix = posterior part of hippocampus with mamillary bodies of hypothalamus (can be divided up into anterior columns, body, commissure and crus)
• stria terminalis = amygdaloid body with anterior hypothalamus and septal nuclei
• mamillothalamic tract = mamillary bodies of hypothalamus with anterior nuclei of thalamus

Question 24

what is anosmia?

Answer 24

loss of sense of smell

Question 25

what's covered in the olfactory mucosa?

Answer 25

superior nasal conchae and the upper part of the nasal septum

Question 26

describe the primary olfactory neurons

Answer 26

- Primary olfactory neurons are bipolar neurons which posses a peripheral and a central process - The peripheral process possesses ciliated receptors that are dispersed throughout the olfactory mucosa - The central processes unit to form olfactory nerves

Question 27

describe the olfactory pathway

Answer 27

* Olfactory nerves enter the skull by passing through the cribriform plate of the ethmoid bone * Olfactory nerves terminate in the olfactory bulb by synapsing with mitral and tufted cells * Axons of the mitral and tufted cells enter the olfactory tract * The fibres of the olfactory tract divide into the medial and lateral striae * Fibres in the medial stria pass through the anterior commissure to the contralateral olfactory bulb * Most fibres enter the lateral stria and project to the primary olfactory cortex

Question 28

what does the primary olfactory cortex consist of?

Answer 28

- uncus | - amygdala

Question 29

where is the thalamus situated? what connects the two?

Answer 29

- contributes to the lateral wall of the third ventricle and extends anteriorly to the interventricular foramen - it lies medial to the posterior limb of the internal capsule and is connected to the opposite side by the massa intermedia (interthalamic adhesion)

Question 30

where is the hypothalamus situated? what does it contribute to?

Answer 30

contributes to the lateral wall of the third ventricle, located inferior to the thalamus – it is attached by the pituitary stalk to the pituitary gland

Question 31

where are the epithalamus and subthalamus located?

Answer 31

* Epithalamus = the most posterior structure of the diencephalon, located rostral to the superior colliculus * Subthalamus = located inferior to the thalamus, dorsolateral to the hypothalamus and superior to the tegmentum of the midbrain

Question 32

what are the mammillary bodies? what are they involved in?

Answer 32

- The mammillary bodies are two rounded elevations that overlie the mammillary nuclei of the hypothalamus - They are involved in limbic function

Question 33

what does the subthalamic nucleus have connections with?

Answer 33

globus pallidus and substantia nigra

Question 34

what are the main components of the epithalamus? what do they do?

Answer 34

- habenacular nucleus - connections with the limbic system | - pineal gland - produces melatonin