lec 3 biology of the mind part 1 (neurons,neurotransmitters etc)

Question 1

What is the path that communications take thru the neuron?

Answer 1

Info received at dendrites –> soma along axon(myelin quickens)–>terminal buttons–>dendrites of other cells at meeting points (synapses)

Question 2

what is the important concept with respect to psychology and biology?

Answer 2

everything psychological is simultaneously biological

Question 3

humans are biopsychosocial systems, what does this mean?

Answer 3

biological, psychological and social cultural factors interact to influence everything we are/do

Question 4

what were the 4 things research discovered when looking at biology of the mind?

Answer 4

-adaptive brain wired by experiences

-nerve cells conduct electricity+communicate thru chemical messages, across tiny gaps

-specific brain systems serve specific functions

-info integrated to construct experiences

Question 5

what are the 2 major types of cells that comprise the nervous system?

Answer 5

Neurons, glial cells (glia)

Question 6

what is the function of neurons? are the easily replaceable?

Answer 6

receive, integrate + transmit info

less able than other cells to replace themselves

Question 7

what are the features of a neuron?

Answer 7

stoma with nucleus
dendrites
axon and myelin sheath
terminal branches

Question 8

what is the function of a glial cell? how often are they replacing themselves?

Answer 8

support + nourishment to neurons, remove waste, insulate axons

constantly replacing themselves

Question 9

what do glial cells play a role in?

Answer 9

thinking, learning + memory

Question 10

what are the 5 parts of a neuron?

Answer 10

Cell body
Dendrites
Axon
Myelin Sheath
Terminal branches of axon

Question 11

What is the function of each part of a neuron?

Answer 11

Cell body- support center

Dendrites- receive messages from other cells

Axon-passes info

Myelin Sheath- insulation, protection, speeds transmission

Terminal branches of axon- form junctions with other cells

Question 12

What is the function of the myelin sheath? When does it develop?

Answer 12

-insulation layer for axon
-protects from unwanted messages from other cells
-speeds up transmission

not present at birth, develops at diff times in diff regions. Stops at age 25

Question 13

What increases during myelination?

Answer 13

-neural efficiency
-judgement
-self control

Question 14

What are the areas where myelin is thin/absent called? What is the purpose?

Answer 14

Nodes of Ranvier, allow ions to diffuse in/out of neuron

Question 15

What happens if the myelin sheath degrades?

Answer 15

-results in multiple sclerosis

-communication to muscles slowed
-eventual loss of muscle control and sometimes sensation

Question 16

how do neurons transmit signals?

Answer 16

electrochemically
-neurons generate electricity from chemical events

Question 17

what are the 2 types of signals a neuron receives?

Answer 17

excitatory(‘the gas’)
inhibitory (‘the brake’)

from many other neurons

Question 18

what is an action potential?

Answer 18

when excitatory signals minus inhibitory signals exceed minimum threshold, neuron fires

Question 19

What causes positive sodium ions to flow into neuron

Answer 19

stimulation (axon firing) causes membrane to open, allowing them to flow in

Question 20

What is resting potential?

Answer 20

the positive/negative state between a neuron outside neuron

neurons ‘at rest’ = negative charge

fluid inside+outside of neuron contain electrically charged ions

Question 21

What is depolarization? What does it influence?

Answer 21

shift from negative to positive voltage in a neuron

influences next section of axon, causing its channels to open

Question 22

What is the refractory period?

Answer 22

sodium channels close, positive potassium ions pumped out of cell

allows cells negative resting potential to be restored

Question 23

what is the all or none response with respect to action potential?

Answer 23

-neuron either fires, or doesn’t
-increasing level of stimulation above threshold will NOT increase intensity of impulse
-intensity of action potential same thruout length of axon

Question 24

How is intensity of a stimulus detected?

Answer 24

strong stimulus causes MORE neurons to fire and fire more OFTEN

Question 25

what is the synapse? where are 3 places connections can occur?

Answer 25

junction b/w terminal button on end of axon from one neuron (pre-synaptic) and either:

1. dendrite of another neuron (post synaptic)
2. membrane of a muscle fiber
3. a gland

Question 26

what is the synaptic cleft?

Answer 26

gap b/w terminal button of pre-synaptic neuron and cell membrane of post synaptic neuron

Question 27

what are neurotransmitters responsible for?

Answer 27

transmitting info from one neuron to another thru synaptic gap

Question 28

where do neurotransmitters bind on post-synaptic cell

Answer 28

after diffusing across synaptic cleft, bind to receptor sites

Question 29

What is important about neurotransmitters binding to receptor sites? What kind of mechanism is it?

Answer 29

each neurotransmitter will bind to specific receptor site

lock and key mechanism

Question 30

what happens to excess neurotransmitters left in synaptic cleft?

Answer 30

either…
1. drift away
2. broken down by enzymes
3. re-absorbed by pre-synaptic neuron, used to produce more later (reuptake)

Question 31

what are neurotransmitters? function?

Answer 31

chemical messengers released by terminal buttons of one neuron so it can communicate with other neurons thru synaptic cleft

each has specific function, sometimes many

Question 32

What is a chemical that increases action of a neurotransmitter called?

Answer 32

agonist

Question 33

What is an antagonist

Answer 33

chemical that blocks/opposes action of a neurotransmitter

key fits, but doesn’t turn lock

Question 34

What does Acetylcholine (ACh) play a role in? What happens if there isn’t enough ?

Answer 34

-learning and memory
-voluntary muscle activity
-ONLY neurotransmitter b/w neurons and motor neurons (reason we move)

inadequate ACh results in type of memory loss seen in Alzheimer’s

Question 35

What is the role of Dopamine(DA)?

Answer 35

-both inhibits+excites neuron, depends on receptor it binds too

-controls voluntary movement

-pleasurable emotions

-affects sleep, mood, attention and motivation

Question 36

What is the dopamine hypothesis?

Answer 36

over activity and under activity in dopamine circuits are associated w/ positive + negative symptoms of schizophrenia

Question 37

What are endorphins?

Answer 37

-natural pain killers (mainly stimulate)
-internally produced chemicals
-shield body from pain
-elevate pleasure feelings

Question 38

What can endorphin disruption lead to?

Answer 38

-behavioral disorders
-increase risk of body aches and pains
-sleep probs
-depression

Question 39

What is the role of Norepinephrine? What happens with too little? too much?

Answer 39

-alertness and arousal

too little: depression
too much: agitated (similar to cocaine effects)

Question 40

What is the role of serotonin?

Answer 40

-mood, hunger, sleep, arousal

too little: depression

Question 41

What happens if you take to much drugs that effect neurotransmitters?

Answer 41

Brain can stop producing neurotransmitter b/c thinks it doesn’t need too

cause of withdrawals