central nervous system

Question 1

main lobes of the brain

Answer 1

frontal, parietal, temporal and occipital

Question 2

end nearest the brain stem

Answer 2

caudal or dorsal

Question 3

end nearest the frontal lobe

Answer 3

rostral or ventral

Question 4

function of the frontal lobe

Answer 4

located at the front of the brain nd associated wit reasoning, motor skills and high level cognition and expressive language

Question 5

when the frontal lobe is damaged

Answer 5

lead to changes in sexual habits, socialisation and increased risk taking

Question 6

function of parietal lobe

Answer 6

between frontal and occipital and on top of temporal

- associated with processing tactile sensory info such as pressure touch and pain

Question 7

when the parietal lobe is damaged

Answer 7

problems with verbal memory; an impaired ability to control eye gaze and problems with languag

Question 8

occipital function

Answer 8

located at the back ( caudal) .

associated with interpreting visual stimuli and info. The primary visual cortex located in this lobe.

Question 9

when the occipital lobe is damaged

Answer 9

visual problems, such as recognising objects, an inability to identify colours and trouble recognising words

Question 10

temporal function

Answer 10

location of primary AVAITORY CORTEX which is important for interpreting sounds and the language we hear. Hippocampus is also located here and is associated with the formation of memories

Question 11

cerebellum

Answer 11

coordination and balance e.g. walking and posture

Question 12

medulla oblongata

Answer 12

helps regulate breathing, heart rate and blood vessel function, digesting, sneezing and swallowing

Question 13

hypothalamus

Answer 13

controls the release of the 8 major hormones

• controls body temp
• controls food and water intake
• sexual behaviour and reproduction

Question 14

pituitary

Answer 14

• endocronic- releases hormones that regulate the function of other endocrine glands
• anterior and posterior

Question 15

pons

Answer 15

control of breathing and communication b/w diff parts of the brain and sensations such as hearing, taste and balance

Question 16

basal ganglia

Answer 16

voluntary motor control, procedural learning and eye movement
-also emotional and cognitive function

Question 17

hippocampus

Answer 17

long term memory

spatial navigation

Question 18

amygdala

Answer 18

detects fear and prepares for emergency events

Question 19

7 main regions of CNS

Answer 19

spinal cord, medulla, the pons, cerebellum, midbrain, diencephalon, cerebral hemisphere

Question 20

parts of the brain responsible for higher functions

Answer 20

e.g. temporal lobe- emotional reaction and understanding language

frontal lobe- decision making

Question 21

lobes responsible for memories

Answer 21

frontal- (prefrontal cortex)- processes long and short term memories
temporal- integrates senses of smell and sound and vision–> needed form long term memories

Question 22

what is long term potentiation

Answer 22

LTP is an increase in efficacy of synapses with repetitive stimulation- therefore increasing synaptic transmission. New synapses will form by splitting pre-existing ones. First discovered to occur in the hippocapmus

Question 23

mechanism of LTP

Answer 23

weak stimulation of the presynaptic neurone will cause the release f the NT Glutamate. The glutamate will bind to both AMPA (inotropic) and NMDA (metabotropic) receptors. However at weak stimulation glutamate will only activate AMPA receptors. This will only cause slight depolarisation. Therefore v.few ions will flow through NMDA channels since they were blocked with Mg2+. If the stimulation is larger than AMDA receptors can depolarise the membrane sufficiently to expel the Mg2+ from the pore. Therefore glutamate will now be able to flow through the NMDA. Ca2+ will also flow through the open NMDA receptor.

Question 24

synaptic plasticity

Answer 24

the ability of a membrane to change its permeability

Question 25

what effect does Ca2+ have on the post synaptic men.

Answer 25

acts as a second messenger and activates a signalling cascade. 1) some Ca2+ will bind to calmodulin and this activates several protein kinases including calcium/calmodulin dependent kinases. 2) Ca2+ also facilities the release of NT from presynaptic axon terminal via retrograde signals, such as NO

Question 26

CAMkinase effects the AMPA receptors in 2 ways

Answer 26

1) phosphorylates AMDA and this increases their conduction to sodium ions 2) CAMK2 promotes the movement of AMPA receptors from intracellular stores into the membrane- therefore more receptors available

Question 27

result of having more AMPA receptors

Answer 27

the response to a stimulus of a given strength will be stronger than it was before NMDA receptors were activated

Question 28

two cognition enhancing drugs

Answer 28

adderall and modafinil all amphetamines work to increase dopaminergic transmission and therefore has a v similar effect on ACh

Question 29

types of NT in the CNS- 6

Answer 29

``` ACH peptides amino acids biogenic amines purines gases and liquids ```

Question 30

ACH receptors in CNS

Answer 30

nicotinic-inotropic | muscarinic- metabotropic

Question 31

role of ACH nicotinic receptors

Answer 31

1) presynaptic and pre terminal receptors enhance nt release 2) postsynaptic receptors mediate a small minority of fast excitatory transmission some have a role in synaptic plasticity therefore they are important modulators if neuronal excitability.

Question 32

what causes myelination in CNS neurones

Answer 32

glial cells called oligodendrites

Question 33

why are not all neurones in the CNS myelinated

Answer 33

sometimes saltatory conduction just isn't needed due to the neuronal distance being so short -also some neurones are responsible for dull, long lasting pain- therefore no benefit to having it transmitted quickly

Question 34

which enzyme synthesises ACH and which breaks it down

Answer 34

acetyl cholinetransferase | acetyl cholinesterase

Question 35

side effect of cognition enhancing drugs

Answer 35

``` organ damage seizures addiction psychotic behaviour malnutrition ```

Question 36

what is the blood brain barrier

Answer 36

a dynamic interact which separates the brain from the circulatory system and therefore protects the CNS from potentially harmful chemicals -formed by a highly specialised endothelial cells that line the brain capillaries and transduce signals from the vascular system and the brain

Question 37

what keep the endothelial cells tight together

Answer 37

tight junctions--> regulated by cytoplasmic proteins--> keeps the integrity of the barrie

Question 38

role of pericytes in BBB

Answer 38

maintains tight junctions and has contractile properties

Question 39

role of astrocytes (glial cells)

Answer 39

maintenance of BBB

Question 40

why is the capillary highly selective

Answer 40

only permeable to molecules like nutrients that won't damage the brain allows waste products, hormones or excess NT to leave the brain few drugs will pass the barrier REQUIRES LIPOPHILICITY