Neuro 6 - Thalamus and Hypothalamus

Question 1

Where is the thalamus found within the brain?

Answer 1

Right in the middle of the brain just under the posterior half of the corpus callosum

Question 2

What separates the two halves of the thalamus?

Answer 2

3rd ventricle

Question 3

Describe the connections of the thalamus with the forebrain.

Answer 3

Each half has ipsilateral connections with the forebrain

Question 4

What is the main function of the thalamus?

Answer 4

Relay centre between cerebral cortex and rest of CNS

Question 5

What is the only function not represented within the thalamus?

Answer 5

Olfaction

Question 6

What is the classification of thalamic nuclei based on and what are the 4 different classes?

Answer 6

The classification is based on the connections of the thalamic nuclei with the cortex
SPECIFIC – connected to primary cortical areas
ASSOCIATION – connected to association cortex
INTRALAMINAR – connected to ALL cortical areas
RETICULAR – not connected to the cortex

Question 7

Which nuclei connect within the motor cortex?

Answer 7

Ventral lateral

Ventral anterior

Question 8

Which nuclei relay sensory information from different parts of the body?

Answer 8

Head - Ventral Posteromedial

Below the neck - Ventral Posterolateral

Question 9

Which nucleus connect with the primary visual cortex?

Answer 9

Lateral geniculate nucleus

Question 10

Which nucleus is connected with the primary auditory cortex?

Answer 10

Medial geniculate nucles

Question 11

The association cortex can be divided into three areas based on thalamic function. What are these 3 areas?

Answer 11

Prefrontal cortex
Pareito-temporal-occipital cortex
Cingulate cortex

Question 12

What do the anterior, lateral dorsal and dorsomedial nuclei connect with?

Answer 12

Prefrontal and cingulate cortex

Question 13

What do the lateral posterior and pulvinar nucleus connect with?

Answer 13

Prefrontal and parieto-tempero-occipital cortex

Question 14

What important system are the intralaminar and reticular nuclei a part of?

Answer 14

Reticular activating system - involved in maintaining conciousness

Question 15

Describe how the reticular nuclei affect cortical activity?

Answer 15

don’t have direct connections with the cortex

but they have widespread intrathalamic connections so can influence the flow of information from other nuclei to the cortex

Question 16

What is the core of grey matter that runs through the brainstem and is involved in the reticular activating system?

Answer 16

Reticular formation

Question 17

How do he intralaminar nuclei modulate the activity of the cortex?

Answer 17

The reticular formation projects up to the thalamus to the intralaminar nuclei

have diffuse cortical projections so can modulate cortical activity

Question 18

What is thalamic syndrome?

Answer 18

syndrome that develops after thalamic stroke

symptoms depend on which part affected

Question 19

What 3 main changes occur in thalamic syndrome?

Answer 19

1) change in sensation
2) pain - central - non localised
3) emotional disturbance

Question 20

Describe the location and structure of the hypothalamus.

Answer 20

just below the thalamus and divided by the 3rd ventricle

Question 21

How is the hypothalamus involved in maintaining homeostasis?

Answer 21

• autonomic nervous system
• endocrine
• behaviour

Question 22

State some forebrain structures that the hypothalamus has very close connections with?

Answer 22

Olfactory system

Limbic system

Question 23

List some structures of the limbic system

Answer 23

hippocampus
amygdala
cingulate cortex
septal nuclei

Question 24

What does the behavioural control exerted by the hypothalamus include?

Answer 24

eating and drinking
emotion
sexual behaviour
circadian rhythm
memory

Question 25

Which nucleus is involved in the circadian rhythm?

Answer 25

Suprachiasmatic nucleus

Question 26

How is behaviour directed towards our homeostatic goals?

Answer 26

Pleasure centre within the limbic system

when you’ve achieved homeostasis, pleasure centre activity increases

Question 27

What are the presenting symptoms of hypothalamic tumour?

Answer 27

Polydipsia
Polyuria
Absent menses

Question 28

What are some later symptoms of hypothalamic tumour?

Answer 28

Rage
Inappropriate sexual behaviour
memory lapses
temperature fluctuation
thyroid
hyperphagia