The Nervous System: The Forebrain

Question 1

Explain the steps of detection and transmission of sensory signals

Answer 1

1. specialised receptor cells respond to environmental changes (connected to sensory neuron)
2. axons of sensory neuron, not in head, enter spinal cord via dorsal root of spinal nerves
3. sensory from head send axons to head via cranial nerves
4. retina= signals integrated with photoreceptors, ganglion cells, bipolar cells (lower processing)

Question 2

When does most info processing occur?

Answer 2

before a signal has reached the brain

Question 3

What direction do neurons transmit signals? and despite what?

Answer 3

one direction despite receiving signals from different sources (higher, lower and same processing areas)
-means every input already decided by brain

Question 4

What structures are in the Brain stem?

Answer 4

Hindbrain and midbrain

Question 5

What structures are in the hindbrain?

Answer 5

Medulla, pons + cerebellum

Question 6

What are the medulla + pons function?

Answer 6

It is where the spinal cord enters the brain and contains several nuclei of ANS

Question 7

What is the function of the cerebellum?

Answer 7

the little brain
responsible for balance and motor learning

Question 8

What does the midbrain do?

Answer 8

its above pons and is responsible for the combination of info from different sense modalities and direction of attention

Question 9

What is inside the forebrain beginning with D and what is inside this?

Answer 9

The diencephalon
The thalamus + hypothalamus

Question 10

What does the thalamus do?

Answer 10

main relay station for SS and receives download-going input from higher areas

Question 11

What does the hypothalamus do?

Answer 11

in front and below of thalamus
It is the gateway to the ES

Question 12

What are the two hemispheres in the cerebrum covered in\/

Answer 12

cerebal cortex (neurons) and contains sub-cortical nucei (cluster of neurons cell bodies)

Question 13

What is inside the forebrain beginning with T and what is inside this?

Answer 13

The telencephalon
The basal ganglia, limbic system, cortex + corpus callosum

Question 14

What is the basal ganglias function?

Answer 14

motor control process
-structures inside referred to as corpus striatum

Question 15

what function does the limbic system?

Answer 15

memory and emotion

Question 16

What are the cortical and sub-cortical areas in the limbic system?

Answer 16

Cortical: cingulate cortex, above corpus callosum
Sub-cortical: almost complete circle formed by fornix and hippocampus

Question 17

What functions does the cerebral cortex have?

Answer 17

perception, action, cognition (signal transfer between hemis)

Question 18

What is the difference between cortex and corpus callosum structures?

Answer 18

cerebral c= thin layers of neurons covering whole hemi
corpus c= thick bundle of axons connecting hemis

Question 19

What creates the folded appearence of the brain found in the cerebral cortex?

Answer 19

gyri- out folded areas
sulci- inward folded areas

Question 20

Outline the signal transmission and interpretation in the brain (SS)

Answer 20

ss from diencephalon relayed to appropriate primary centre cortex (all these signs are identical- depending on location for interpretation

Question 21

Outline signal transmission and interpretation in the brain (topographic maps)

Answer 21

inside sensory areas, signals arrive at a similar position of receptor cells (topographic representation)

Question 22

Why are there different maps for signal transmission?

Answer 22

for sense modaility

Question 23

What does the somatotopic map do?

Answer 23

Signal from hand arrives at somatosensory area, which is next to arm, next to shoulder

Question 24

What does the retinotopic map do?

Answer 24

visual signals from neighbouring retinal positions arrive at neighbouring positions in visual cortex

Question 25

What does a tonotopic map do?

Answer 25

auditory signals from adjacent areas of chochlea arrive at adjacent areas in auditory cortex

Question 26

What does the supplemetary premotor and motor cortex do?

Answer 26

involved in planning and guidance of sensory movements

Question 27

What does the primary motor cortex do?

Answer 27

motor neurons send axons to spinal cord