MBB1

Question 1

lecture 1

history of the brain

Answer 1

. adult weight is around 1400 grams

. 3% of our body weight and 20% of our energy resources are found in our brain

. Hippocrates said it was the centre of control

. Galen discovered sensory and muscle nerves

. Vesalius discovered the cortex which is composed of our gyri and sulci and meninges

. Descartes discovered link between the physical brain and non physical mind

. Galvani noticed that there is electricity that occurs with neural communication

. Gall noticed that facial features can be matched to our personality

. Broca discovered that the LFC is the site of expressive language

. Moniz relieved anxiety with Prefrontal leucotomy which is now banned

Question 2

lecture 2 - M.S and neuron function

• what are symptoms of MS

Answer 2

paraplegia, weakness, numbness, visual problems and slurred speech

• this is because their immune system attacks the myelin sheath that surrounds our axons of neuron disturbing the transmission of action potential/stops communication

Question 3

lecture 2 - MS and neuron function

• what is the role of myelin sheath?

Answer 3

allows electrical impulses to transmit quickly and efficiently along the nerve cells

Question 4

lecture 2 - MS and neuron function

-functioning of a cell

Answer 4

. Dendrites allow neurons to communicate

. Axon is a passage that carries signals from the cell body

. Action potential is the signal that gets carried

. Terminal buttons secreted neurotransmitters to either excite or inhibit

. Cytoplasm has mitochondria which uses glucose to produce energy

Question 5

lecture 2 - MS and neuron function

what does a change in membrane permeability cause?

Answer 5

action potential

Question 6

lecture 2 - MS and neuron function

4 types of glial cells

Answer 6

1. astrocytes which provide physical support and clean up waste to keep the extracellular fluids around cells in good condition
2. oligodendrocytes which TOO give physical support but also insulation to axons alongside myelin
3. microglia which act as phagocytes
4. schwann cells which are like oligodendrocytes but for the PNS

Question 7

lecture 2 - MS and neuron function

depolarisation

Answer 7

…occurs when a positive electrical current passes through making the sodium channels open

…membrane potential goes from a negative charge to a positive

…the current must be between -70mvs to 40mvs

Question 8

lecture 2 - MS and neuron function

repolarisation

Answer 8

…occurs after depolarisation and potassium channels now open to bring back a balance as there is too much positive potassium now in the axon

Question 9

lecture 2 - MS and neuron function

refractory period

Answer 9

…occurs when sodium channels close and cannot re open until the membrane reaches its resting potential again which is -70mvs

Question 10

lecture 2 - MS and neuron function

role of the sodium potassium pump

Answer 10

…allows a cell to have both sodium and potassium inside during the change in membrane potential which is crucial for normal functioning

Question 11

lecture 2 - MS and neuron function

hyperpolorisation

Answer 11

…potassium ions start to move out and the process of action potential can start again

Question 12

lecture 2 - MS and neuron function

what medicine can be administered to allivieate MS

Answer 12

interferon b - aids the Nodes of Ranvier which have been disrupted

Question 13

lecture 2 - MS and neuron function

what are the advantages of the action potential jumping along myelinated axons

Answer 13

1 it saves energy

2 it increases the speed therefore our reaction time is faster

Question 14

lecture 2 - MS and neuron function

where are sodium ions most concentrated?

Answer 14

…outside of the neuron making the membrane potential more positive

…efflux of potassium however makes the membrane potential more negative

Question 15

lecture 3

what is myasthenia gravis?

Answer 15

…a disorder of synaptic transmission

Question 16

lecture 3

steps of neurotransmitter release

Answer 16

1. enzymes
2. NT release from the top
3. NT binds to vesicles
4. some enzymes degrade
5. those that haven’t leave the pre synapse and attach to the post synaptic receptor

Question 17

lecture 3

EPSP vs IPSP

Answer 17

EPSP - depolorises the postsynaptic cell and increases the chance of an action potential

IPSP - hyperpolorises the postsynaptic cell and decreases the chances of an action potential

Question 18

lecture 3

what is reuptake?

Answer 18

occurs in the synaptic cleft and ensure there are no lingering NTs that did not make it into the postsynapse

Question 19

lecture 3

what is enzymatic deactivation?

Answer 19

…deactivates enzymes after termination of postsynaptic potentials

Question 20

lecture 3

types of amino acids and what they do

Answer 20

firstly, amino acids give our cells structure - building blocks

… one type is GABA which are inhibitory
… second is glutamate which are excitatory
…monomines which include seretonin and dopamine
… and then there are acetlycholine

Question 21

lecture 3

agonist drugs vs antagonist

Answer 21

agonist - increase flow in synapse

antagonist - decrease ion flow at synapse

Question 22

lecture 4 - structure and function of nervous system

• positions of our brain

Answer 22

1. rostral (anterior)
2. caudal (posterior)
3. dorsal (fin/up)
4. ventral (heart/below us)

Question 23

lecture 4 - structure and function of nervous system

the meninges and what is involved in the meninges structure

Answer 23

the main role of the meninges is to protect our CNS and is made up of:

1. the dura mater - protects skull
2. arachnoid mater - allows CSF to flow through
3. pia mater - only the PNS has pia mater and dura mater

Question 24

lecture 4 - structure and function of nervous system

CSF

Answer 24

…is created by chorois plexus and re-absorbed into bloodstream. The lateral ventricle lets it flow out
…those with a blockage of CSF get a condition called obstructive hydrocephalus

Question 25

lecture 5 - structure and function of nervous system what do darker ares of the brain show?

Answer 25

...more neuron cell bodies

Question 26

lecture 5 - structure and function of nervous system hypothalamus vs thalamus

Answer 26

H --> controls our autonomic nervous system and endocrine system which regulates our survival behaviours T --> the relay station for sensory inputs to the cerebral cortex

Question 27

lecture 5 structure and function of nervous system the spine

Answer 27

...we have 24 vertebrae in the spine ...spinal foramen is where the spinal cord passes through ...31 pairs of spinal nerves that receive and convey information ...12 cranial nerves associated with the sending and receiving of signals

Question 28

lecture 6 - methods of testing peoples biological systems

Answer 28

...clinical neuropsychology attempts to explain brain behaviour relationships by looking at functioning patterns after damage. To be able to do this researchers look at patterns of association and dissociation ...limitations of clinical neuropsychology is that it cannot test in depth, hard to replicate and assumptions can be made that are incorrect

Question 29

lecture 6 - methods of testing people overcoming limitations of clinical neuropsychology with ablation studies

Answer 29

...ablation studies are means of testing animals

Question 30

lecture 6 broca aphasic vs wernickes aphasia

Answer 30

B.A --> loss of speech | W.A--> cannot comprehend language

Question 31

lecture 6 | other methods of testing (other than clinical neuropsychology and ablation)

Answer 31

1. structural brain imaging - ct scans and MRI | 2. functional brain imaging - EEG, ERP AND fMRI

Question 32

lecture 6 - methods of testing | fMRI

Answer 32

fMRI looks at oxyhaemoglobin which is diamagnetic and deoxyhaemoglobin levels which is paramagnetic

Question 33

lecture 7 - visual system | cells of our retina

Answer 33

...1. ganglion cells ...2. bipolar cells ...3. photoreceptor layer signals from cones and rods go from the bipolar cels to the ganglion cells photoreceptor and bipolar cells do not produce action potentials instead they release neurotransmitters that either increase of decrease the firing rate of action potentials that are generated by ganglion cells the retina has around 120million rods and 6 million cones

Question 34

lecture 7 - visual system wavelengths of cones

Answer 34

shortwavelength - blue light and most sensitive to 440nm midwavelength - green light and most sensitive to 500nm long wavelength - red light and most sensitive to 560nm

Question 35

lecture 7 - visual system rods vs cones

Answer 35

cones - active when there is more light and colour rods - active when it is dark/monochromatic light

Question 36

lecture 7 - visual system | ON and OFF cells

Answer 36

within the ganglion and bipolar cells; ON cells are excited by light in their centre and inhibited by light in their surrounding field OFF cells are inhibited by light in their centre and excited by light in their surrounding areas ...a bar of light that passes over the oN region will increase firing rate of neuron and a bar of light that passes over the OFF region will decrease firing rate

Question 37

lecture 7 - visual system | areas of vision in the brain

Answer 37

Primary visual cortex - V1/ injuries to this causes interruption of flow of visual info to the brain V4 - neurons sensitive to colour MT - neurons sensitive to movement Inferior temporal cortex - aids recognition of complex objects and faces damage to v4 - see things in black and white damage to MT - akinestopsia/ unable to judge speed propsopagnosia - cannot recognise famous faces

Question 38

lecture 8 - auditory system - basic knowledge; key words

Answer 38

as humans we can hear from 30-20,000 Hz loudness = amplitude pitch = frequency timbre = complexity - inner ear contains the cochlea which is the most important system for our hearing as sound waves cause the stapes to move in and out making fluid movement to the baslir membrane

Question 39

lecture 8 - auditory system how we hear

Answer 39

bending of hair cels is what produces receptor potentials converting sound waves in neural signals

Question 40

lecture 8 - auditory system cochlea implantation

Answer 40

- creates more excitation of inner hair cells while decoding complex sounds into individual frequencies

Question 41

lecture 8 - auditory system what is the somatosensory system?

Answer 41

- is the part of the sensory system concerned with the conscious perception of touch, pressure, pain, temperature, position, movement, and vibration, which arise from the muscles, joints, skin, and fascia - within this is cutaneous sense which is incharge of touch e.g. pain

Question 42

lecture 8 - auditory system | skin properties

Answer 42

hairy skin has rapid vibrations and free nerve endings that detect a change in temperature glabrous skin = a more complex array of receptors found in areas that need is such as our fingers, mouth and palms meissners corpuscles = are nerve endings that respond to taps, light touches and frequent vibrations (10-50Hz) morkels disks = respond to indenting of skin nocirecptor = respond to pain ATP receptors = respond to muscle damage Capsaicin receptors = respond to extreme heat mechanoreceptors = respond to hitting, stretching or pinching Phantom limbs = sensations from a limb that are no longer there

Question 43

lecture 9 - sensorimotor system how are our muscles fibres stimulated?

Answer 43

...neural signals from motor neurons in our spine exit via the ventral root to create an action potential which releases acetylcholine that stimulates the muscle fibres to change their length accordingly to perform the movement

Question 44

lecture 9 - sensorimotor system flexors, extensors, muscle spindles, reflex arc

Answer 44

flexors = flex a joint extensors = straighten a joint muscle spindles = provide information to the CNS regarding muscle lenght reflex arc = helps maintain position of body such that when someone bumps you when you have hot tea for example your stretch reflex compensates to prevent you from falling over and spilling this hot tea over you that would hurt you can test your relex arc with a patellar tendon test

Question 45

lecture 9 - sensorimotor system hierarchical organisation in sensorimotor system in the brain

Answer 45

1. highest level of control patterns = association cortex e.g. prefrontal cortex and parietal 2. motor cortex 3. primary motor cortex 4. brainstem motor nuclei 5. spinal motor circuits

Question 46

lecture 9 - sensorimotor system senses controlled in the brain

Answer 46

...basil ganglia - controls motor behaviour such as sequencing of movement and voluntary movement ...huntingdons disease and parkinsons are due to damage to the basil ganglia ...lesions to cerebellum disrupts a persons ability to control direction, force etc. of voluntary movements and cannot adjust to walking on different surfaces such as a bumpy road