Structure And Function Of The Central Nervous System Flashcards
(62 cards)
1
Q
What are the cerebral hemispheres?
A
- two half globes
- cerebrum = the largest portion of the brain in terms of volume
2
Q
What is the surface of the cerebrum characterised by/
A
- thick folds called gyri
- grooves called sulci
3
Q
Where is the pre central gyrus compared to the central sulcus?
A
Above it
4
Q
Where is the post central gyrus compared to the central sulcus?
A
Below it
5
Q
What separates the cerebral hemispheres?
A
- longitudinal fissure
6
Q
How to the cerebral hemispheres communicate with each other?
A
- via the corpus callosum
7
Q
Structure of the corpus callosum:
A
- cerebral cortex = grey matter = outer layer
- white matter = inside layer
- corpus callosum = right up the middle
- has basal ganglia
- temporal lobe = bottom left
- internal capsule = middle ish
8
Q
What is the outer layer of the cerebrum?
A
- grey matter / cerebral cortex
- has very little myelin
9
Q
What is the inner layer of the cerebrum?
A
- inner white matter
- myelin rich
10
Q
How many lobes does the cerebral cortex have?
A
- four
11
Q
What is the function of the frontal lobe?
A
- intelligence = problem solving
- moral judgement
- voluntary motor activity
- speech articulation
12
Q
What is the prefrontal area of the frontal lobe associated with?
A
- intelligence
- problem solving
- moral judgement
13
Q
What is the motor area of the frontal lobe associated with?
A
- control of skeletal muscle activity
14
Q
What is Broca’s area of the frontal lobe associated with?
A
- articulation of speech
15
Q
What is the function of the parietal lobe?
A
- sensory functions
- primary
- somatic
- somatic interpretive areas
16
Q
What is the function of the temporal lobe?
A
- hearing
- forming long term memories
- language use
- comprehension
17
Q
What are the primary auditory & auditory interpretive areas of the temporal lobe’s functions’?
A
- linked to hearing
18
Q
What is the function of Wernicke’s area of the temporal lobe?
A
- language use
- comprehension
19
Q
What is the function of the occipital lobe?
A
- vision
20
Q
What are the functions of the primary visual and visual interpretative areas of the occipital lobe?
A
- enable the perception of visual stimuli
21
Q
What is the limbic system?
A
- a ring of interconnected structures underneath the cerebral cortex
22
Q
What is the function of the limbic system?
A
- to generate emotions and motivational drives
23
Q
Limbic system structure description:
A
- cingulate gyrus = outer layer
- hippocampus
- amygdaloid body = end of hippocampus
- mammillary body = just in from amygdaloid
- hypothalamus = just in from that
- thalamic nuclei = just in from that
- parahippocampal gyrus = just in from hippocampus
- pineal gland = beside parahippocampal
- corpus callosum = just in from the hippocampus at top
- formix = inner bit
24
Q
What allows neuronal transmission in the limbic system?
A
- serotonin
25
What may depression be caused by?
- deficiency of serotonin in the brain
- due to it being characterised my misery & apathy
- this is why antidepressant drugs are used
26
How do antidepressant drugs work?
- inhibit the reuptake of serotonin from the synaptic cleft
- allowing it to have more time to excite the post synaptic neurones
- known as = selective serotonin reuptake inhibitors
27
What do stimulation of punishment areas do?
- evoke fear in humans
- evoke defensive behaviour in other animals
28
What does stimulation of reward areas do?
- humans = feeling of well-being
- other animals = placid behaviour
29
What does stimulation of punishment and reward areas do?
- helps the brain decide what information is kept as memories and what should be discarded
- as sensory experiences that do not activate a response, aren’t likely to be remembered
30
Most potent reward area?
- the nucleus accumbens in the hypothalamus
- known as the pleasure centre
31
What are reward responses dependent on?
- the neurotransmitter = dopamine
32
How do illegal drugs become addictive?
- they activate a reward response in the nucleus accumbens
- cocaine, methamphetamine
- codeine can initiate a reward response as well
- this is why they are labelled for three days of use only, as they can start an addiction
33
What is the hypothalamus mainly important for?
- controlling a range of homeostatic functions
- regulating appetite
- body water
- body temperature
- control of pituitary gland secretion
- fight or flight response
34
What is the amygdala responsible for?
- initiating sexual behaviour
- erections
- ejaculation
- ovulation
- uterine activity
35
What is the hippocampus responsible for?
- important for the formation of long term memories
36
What happens if the hippocampus is removed?
- causes anterograde amnesia
- unable to form long term memories
37
What exactly is a memory?
- changes in the sensitivity of synaptic transmission between neurones,
- which occurs as a result of previous neuronal activity
38
What are neuronal circuits called?
Memory traces
39
Where are elements of a memory stored?
- visual elements = occipital lobe
- auditory elements = temporal lobe
40
How does a memory trace become a long term memory?
- there must be an increase in the number of pre synaptic terminals connecting a series of neurones
41
What is a short term memory known as?
- a temporary memory trace
- the structural change does not occur
42
What does the hippocampus decide?
- whether a sensory experiences is important enough to be stored as a long term memory
43
What is the thalamus?
- mass of grey matter under the cerebral hemispheres, but above the midbrain of the brain stem
44
What do all pathways from sensory receptors and organs do with the thalamus?
- go through the thalamus to get to the cortex
45
What does every individual area of the thalamus activate?
- its own specific region of the cortex
46
Why is activation of each specific area of the cortex vital?
- disruption of signals travelling to the cortex from the brain stem can cause an unremitting coma
47
Why is the thalamus important for memory retrieval?
- damage to thalamic areas leads to retrograde amnesia
- not able to access your long term memories
48
What does the brain stem link?
- links the spinal cord with the higher centres of the brain
49
What region is farthest from the spinal cord and what does it do?
- midbrain
- concerned with pupillary responses of the eyes and eyeball orientation
50
What area is below the midbrain and what does it do?
- pons
- control of urination
- pneumotaxic centre = controls the rate and depth of breathing
51
Why does the pneumotaxic centre communicate with the lowest region of the brain stem, the medulla oblongata?
- to control the rate & depth of breathing
52
What is called the respiratory centre?
- pons & medulla oblongata of the brain stem
- neurones within it stimulate muscles to contract for inspiration to happen
53
What controls cardiac output and blood pressure?
- medulla oblongata
- pons
54
What is the cardioacceleratory centre?
- the output that increases heart rate
55
What is the vasomotor centre?
- controls blood vessel diameter
56
What does the cardiac slowing area do?
- slows the heart down
57
What is the spinal cord?
- a cylinder of nervous tissue, which starts in the brain stem and passes through the vertebral canal
58
How many regions does the spinal cord have?
- five
59
What is a function of the spinal cord?
- it carries both ascending and descending signals
60
Ascending (sensory) pathway?
- sensory neurone
- to brainstem
- to brain
61
Descending (motor) pathway?
- brain
- brainstem
- muscle is effected by
62
What is the other function of the spinal cord?
- mediates reflexes, protective in nature
- mediates defaecation & urination
