Thalamus and hypothalamus

Question 1

Where is the thalamus

Answer 1

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

Question 2

What is in the middle of the two halves of the thalamus

Answer 2

The third ventricle

Question 3

What does ipsilateral mean?

Answer 3

Belonging to or occurring on the same side of the body

Question 4

What is the function of the thalamus?

Answer 4

It is a relay centre between the cerebral cortex and the rest of the CNS. There is also integration and modification of information as it goes through the thalamus

Question 5

There is a nucleus within the thalamus for pretty much every function except for one, which one?

Answer 5

Olfaction

Question 6

What is the classification of thalamic nuclei based on?

Answer 6

It is based on the connection of the nuclei with the cortex (SARI):
Specific- Connected to primary cortical areas
Association- Connected to associated cortical areas
Reticular- Not connected to the cortex
Intralaminar- Connected to all cortical areas

Question 7

What are the two thalamic nuclei that relay sensory information?

Answer 7

Ventral posterolateral- Below the neck

Ventral posteromedial- Head

Question 8

What do the lateral geniculate and medial geniculate relay information from?

Answer 8

Lateral- From retina to primary visual cortex

Medial- From inner ear to primary auditory cortex

Question 9

What is the prefrontal cortex?

Answer 9

Most of the frontal lobe except from the primary motor cortex and some other motor cortical areas

Question 10

What is the parietno-tempero-occipital cortex?

Answer 10

Consists of all the cortex in the parietal, temporal and occipital lobes except for the primary cortical areas

Question 11

Where is the cingulate cortex?

Answer 11

It follows the line of the corpus callosum

Question 12

What does the reticular activating system do?

Answer 12

Maintains consciousness- consists of intralaminar and reticular nuclei

Question 13

How do the reticular nuclei have an indirect effect on the cortex?

Answer 13

The reticular nucleus has no direct connections with the cortex but has intrathalamic connections with pretty much all other nuclei. Because of this, it is able to influence the flow of information through the other nuclei to the cortex

Question 14

What is the reticular formation?

Answer 14

Core of grey matter through the brainstem which projects up to the thalamus

Question 15

How does reticular formation activity affect cortex activity

Answer 15

The greater the level of activity through the reticular formation, the greater the activity of the cortex so the greater level of consciousness

Question 16

What are the symptoms of thalamic syndrome?

Answer 16

The symptoms often depend on what part of the thalamus has been affected, normally it affects sensation and pain. There is either reduced or exaggerated sensation. There is also central, non-localised pain. There is also emotional disturbance

Question 17

What is the limbic system?

Answer 17

Circuit of structures within the forebrain thats involved with setting your mood and controlling your emotions

Question 18

Where is the hypothalamus

Answer 18

Below the thalamus

Question 19

What is the hypothalamus divided by?

Answer 19

3rd ventricle

Question 20

What two structures are seen just in front of the hypothalamus?

Answer 20

Optic chiasm and pituitary stalk

Question 21

What is the function of the hypothalamus?

Answer 21

It is involved in homeostasis and coordinates autonomic nervous system, endocrine system and behaviour

Question 22

What structures in the forebrain does the hypothalamus have very close connections with?

Answer 22

Olfactory system and limbic system

Question 23

What does behavioural control include?

Answer 23

Eating and drinking, expression of emotion, sexual behaviour, circadian rhythm and memory

Question 24

Which nucleus is involved in controlling circadian rhythm?

Answer 24

Suprachiasmatic

Question 25

What are the effects of a hypothalamic tumour?

Answer 25

Symptoms- Polydipsia, polyuria, labile emotions, rage, inappropriate sexual behaviour, memory lapses, temperature fluctuation, decrease in thyroid, adrenal and gonadal function and hyperphagia