bbb 2 Flashcards
(233 cards)
1
Q
How much does the brain weigh on average?
A
1.5 kg,
2
Q
Which neurone is most frequently found in the brain?
A
Interneurons (Relay neurons),
3
Q
What are the two neuron ‘processes’? (2)
A
- Axons 2. Dendrites,
4
Q
What is the function of axons?
A
Transmit information from the neuron onto the others to which it is connected.,
5
Q
What is the function of dendrites?
A
They receive the information being transmitted by the axons of other neurons.,
6
Q
What are the functions of the spinal cord? (2)
A
- Simple and complex reflexes 2. It forms a highway between the body and the brain for information travelling in both directions.,
7
Q
What is the diencephalon is divided into? (2)
A
- Thalamus 2. Hypothalamus,
8
Q
Function of the basal ganglia
A
Has a central role in the initiation and control of movement.,
9
Q
How are the left and right hemispheres connected?
A
Corpus Callosum,
10
Q
Who drew the first pictures of neurons and denrites?
A
Ramon y Cajal in 1890,
11
Q
How do dendrites change shape?
A
They sprout new connections and withdraw others,
12
Q
What are dendritic spines?
A
Tiny protuberances that stick out from the dendrites,
13
Q
Function of dendritic spines
A
These are where incoming axons make most of their connections.,
14
Q
What do the end-points of the axons respond to?
A
Growth factors,
15
Q
How do growth factors influence axons?
A
These factors are taken up inside and then transported to the cell body where they influence the expression of neuronal genes (manufacture of new proteins). These enable the neuron to grow longer dendrites or make dynamic changes to its shape or function.,
16
Q
Where does the word ‘synapse’ stem from?
A
Classical Greek words that mean “to clasp together”.,
17
Q
What happens when the dendrite receives a chemical messenger? (2)
A
Miniature electrical currents are set up inside the receiving dendritic spine these are either: 1. Currents that come into the cell (excitation) 2. Currents that move out of the cell (inhibition),
18
Q
What does the myelin sheath do?
A
It prevents the ionic currents from leaking out in the wrong place,
19
Q
What do clusters of ion channels serve to do?
A
Boost and maintain the action potential as it skips along the nerve.,
20
Q
Where are neurotransmitters found?
A
Synaptic vesicles in the endings of axons.,
21
Q
What happens after neurotransmitters are released into the synaptic cleft? (2)
A
- Attaches to post-synapse receptors 2. Returns into the synaptic cleft by transporters on glial cells,
22
Q
What are ionotropic receptors?
A
When the attachment of the transmitter (the key) to the receptors (the lock) causes the opening of an ion channel,
23
Q
What is the main excitatory neurotransmitter in the brain?
A
Glutamate,
24
Q
What are the names of the inhibitory neurotransmitters? (2)
A
- GABA 2. Glycine,
25
What are the characteristics of metabotrophic receptors? (3)
1. Do not contain ion channels 2. Are not localised in the region of the synapse 3. Do not lead to the initiation of action potentials,
26
What is the action of metabolic receptors called?
Neuromodulation,
27
What receptors neuromodulate?
Metabotrophic receptors,
28
Where are metabotrophic receptors found?
In complex particles linking the outside of the cell to enzymes inside the cell that affect cell metabolism.,
29
What effects can neuromodulation cause? (4)
Changes in: 1. Ion channels 2. Receptors 3. Transporters 4. Expression of genes,
30
Which messengers act on G-protein coupled receptors? (3)
1. Acetylcholine 2. Dopamine 3. Noradrenaline,
31
What is noradrenaline?
Noradrenaline is released in response to various forms of novelty and stress and helps to organise the complex response of the individual to these challenges. Lots of networks may need to “know” that the organism is under stress.,
32
How does acetylcholine work ionically?
It uses ionic mechanisms to signal across the neuromuscular junction from motor neurons to striated muscle fibres.,
33
What receptors does actylcholine work on?
Ionotropic and metabotropic receptors.,
34
How can actylcholine act as a neuromodulator?
When you want to focus attention on something - fine-tuning neurons in the brain to the task of taking in only relevant information.,
35
What ability do addictive drugs share?
They promote the release of the chemical messenger dopamine in certain brain regions.,
36
How does alcohol work?
Alcohol acts on neurotransmitter systems in the brain to dampen down excitatory messages and promote inhibition of neural activity.,
37
How does nicotine work?
Nicotine acts on brain receptors that normally recognise the neurotransmitter acetylcholine; it tends to activate natural alerting mechanisms in the brain.,
38
Consequence of alcoholism (2)
1. Damages the body (liver and brain) 2. Pregnant mothers who drink run the risk of having babies with damaged brains and low IQ’s.,
39
Consequence of a nicotine addiction
Tobacco smoke is extremely damaging to the lungs and long-term exposure can lead to lung cancer and also to other lung and heart diseases.,
40
What two neurotransmitters do amphetamines release? (2)
1. Dopamine (strong arousal and pleasurable effects) 2. Serotonin (sense of well-being and a dream-like state that can include hallucinations).,
41
What are the consequences of amphetamine use? (3)
1. Permanent reduction of serotonin cells. 2. Death 3. Schizophrenia-like psychosis,
42
How does heroin work?
It hijacks a system in the brain that employs naturally occurring neurotransmitters known as endorphins (pain control).,
43
How does cocaine work?
Cocaine makes more dopamine and serotonin available in the brain.,
44
What aspect of touch do the Pacinian and Meissner corpuscles respond to? (2)
Sense of: 1. Vibration 2. Flutter,
45
What aspect of touch does Merkel's disk respond to?
Sense of pressure,
46
What aspect of touch do Ruffini endings respond to?
Slowly changing indentations,
47
Which corpuscle has the largest receptive field?
Pacinian,
48
What happens once a somatosensory receptor detects a stimulus?
The receptors send impulses along the sensory nerves that enter the dorsal roots of the spinal cord.,
49
How is touch involved in the active control of movement?
Neurons in the motor cortex controlling the muscles in your arm that move your fingers get sensory input from touch receptors in the finger tips.,
50
Why is it unsurprising that touch has a relationship with motor?
The primary sensory and motor cortices are right beside each other in the brain.,
51
What is a pain receptor called?
Nociceptor,
52
What types of stimulus do nociceptors respond to? (3)
1. Heat above 46C 2. Tissue acidity 3. The active ingredient of chilli peppers.,
53
What peripheral afferent fibres repond to noxious stimuli? (2)
1. Αδ fibres 2. C fibres,
54
What is noxious stimuli?
An actually or potentially tissue damaging event,
55
Which parts of the brain deal with pain? (2)
1. Anterior cingulate (ACC) 2. Insular,
56
Why is pain important? (2)
1. Allows us to learn and avoid threatening situations 2. Inhibit activity to allow healing,
57
How is pain supressed in a survival situation?
Via the release of endogenous analgesics,
58
What can be done to elevate the pain threshold?
Electrically stimulate the aqueductal grey matter,
59
What chemical transmitters are involved in pain mediation?
Endogenous opioids,
60
What is an example of an endogenous opioid?
Met-enkaphalin.,
61
What receptors does morphine act on?
The same receptors at which some the endogenous opioids act.,
62
What is enhanced pain called?
Hyperalgesia,
63
What are the symptoms of hyperalgesia? (4)
1. Lowering of the pain threshold 2. An increase in the intensity of pain 3. A broadening of the area over which pain is felt 4. Pain in the absence of noxious stimulation.,
64
What causes hyperalgesia?
Sensitisation of the peripheral receptors as well as complex phenomena at various levels of the ascending pain pathways.,
65
How does the human eye detect light?
Light entering the eye is focused by the lens onto the retina located at the back. Receptors there detect the energy and by a process of transduction initiate action-potentials that travel in the optic nerve.,
66
Which photoreceptor is more sensitive to light?
Rods are 1000 times more sensitive to light than cones.,
67
Which photoceptor do you use during the day and which at night?
You see at night with your rods but by day with your cones.,
68
What is phototransduction?
The conversion of light into electrical signals in the rods and cones,
69
What feature of the eye projects to the brain?
The optic nerve,
70
Where do the fibres of the optic nerve meet?
At the optic chiasm,
71
What happens to the fibres of the optic nerve once they've met at the optic chiasm?
Half of them “cross” to the other side where they join the other half from the other optic nerve that have stayed “uncrossed”.,
72
What are the connected pathways of the optic nerves called?
Optic tracts,
73
How do optic tracts project to the cerebral cortex?
Via a synaptic relay in a structure called the lateral geniculate nucleus,
74
What is it called since the occipital lobe reponds to imput from either eye?
Binocularity,
75
What is a receptive field (vision)?
The region of retina over which the cell will respond to the prefered kind of image.,
76
Which is the first stage of cortical processing (vision)?
V1,
77
What do the V1 neurones respond to?
Lines or edges in a particular orientation.,
78
How does blind sight work?
It is probably mediated by parallel connections from the eyes to other parts of the cortex.,
79
What does the activity of the cells in V5 reflect?
It reflects the strength of the movement signal.,
80
What does V5 do? (2)
1. Register the motion of visual stimuli 2. Register perceived motion,
81
What does 'EMGs' stand for?
Electro-myographic recordings,
82
How can EMGs be used?
To measure the level of activity in each muscle,
83
What is a population code?
Actions are specified by the firing of an ensemble of neurons. (such as with movement),
84
What is the function of the pre-motor cortex? (3)
1. Planning actions 2. Preparing spinal circuits for movement 3. Establish links between seeing movements and understanding gestures.,
85
Why are mirror neurones important?
They are important in imitating and understanding actions.,
86
What is behind the motor cortex?
Parietal lobe,
87
Where do the basal ganglia send impulses?
Motor cortical areas,
88
What area of the brain causes Parkinson's disease?
Degeneration of neurons in an area of the brain called the substantia nigra,
89
What part of the brain does alcohol have a big effect on?
Cerebellum,
90
Functions of the cerebellum (3)
1. Skilful smooth movements 2. Motor learning and adaptation 3. Optimal adjustment (timing),
91
What symptoms occur when there is damage to the cerebellum? (4)
1. Poorly coordinated movements 2. Loss of balance 3. Slurred speech 4. Cognitive difficulties,
92
What areas are in the anterior half of the cortex? (4)
1. Sensory 2. Motor 3. Prefrontal 4. Limbic regions,
93
Which structure does the brain form from in early embryonic development?
Neural plate,
94
How does the neural tube form?
The neural plate rolls up,
95
What happens if the neural tube fails to close (at the lower end)?
Causes spina bifida (a condition confined to the lower spinal cord),
96
What happens when the head of the neural tube fails to close?
Causes the complete absence of an organised brain (anecephaly),
97
What is 'patterning' and why is it necessary in brain formation?
A mechanism resulting in fine levels of resolution causing neurones to obtain an individual identity,
98
Why is patterning in brain formation essential?
Cells get to know their position relative to the principal axes of the nervous system. Each cell measures its position with respect to these orthogonal coordinates.,
99
What happens after a neuron has aquired its individual identity?
It stops dividing and extends its axon with an englarged tip known as a growth cone,
100
Why do new neurons have axons with growth cones?
It is specialised for moving through tissue using its skills to select a favourable path,
101
What happens once a growth cone has reached its desired destination?
The growth cone loses its power of movement and forms a synapse,
102
What is it called when the growth cone on the axon grows towards where it needs to go?
Axonal guidance,
103
How do growth cones find their way?
Guidance cues that attract (+) or repel (-) the growth cones. The molecular mechanisms responsible for regulating the expression of these cues remain poorly understood.,
104
When are the majority of initial conntects made?
During the critical period (this finished after 1 year in humans),
105
What is the alphabetic visual symbols (in the right order) of a language called?
Orthography,
106
What allows symbols (alphabets) to be translated into the correct sounds?
Phonemic structure,
107
What is visuomotor integration?
The letters are identified during each fixation of the eye but their order is given by where the eye was pointing when each letter was seen. What the eyes see has to be integrated with motor signals from the eye movement system.,
108
What conducts visual control of the eye movement system?
The magnocellular system,
109
What does the magnocellular cells in a dyslexic look like?
Disorganisation of of the lateral geniculate nucleus.,
110
How do we distinguish letter sounds (phonemes)?
Detecting the subtle differences in the sound frequency and intensity changes that characterise them. Detecting these acoustic modulations is carried out by a system of large auditory neurons that track changes in sound frequency and intensity.,
111
What is the link between a dyslexics clumsiness and poor handwriting?
The magnocellular system provides a large input to the cerebellum,
112
What two processes cause long-lasting changes in synaptic strength due to brief periods of neuronal activity?
1. Long-term potentiation (LTP) 2. Long-term depression (LTD),
113
Where are glutamate receptors found?
On the receiving side of the synapse,
114
What are the 4 types of glutamate receptors? (2)
1. 3 ionotrophic receptors 2. 1 metabotrophic receptor,
115
What are the 3 ionotrophic glutamate receptors called? (3)
1. AMPA 2. NMDA 3. Kainate,
116
What is the 1 metabotrophic glutamate receptor called?
mGluR,
117
What are the fuctions of the ionotrophic and metabotrophic glutamate receptors? (2)
1. The ionotropic glutamate receptors use their ion channels to generate an excitatory post-synaptic potential (epsp) 2. The metabotropic glutamate receptors modulate the size and nature of this response,
118
Which glutamate receptor acts the quickest?
AMPA,
119
What is the function of NMDA?
Trigger synaptic plasticity,
120
Which neurotransmitter is associated with heightened attention?
Acetylcholine,
121
Which neurotransmitters are associated with stress and anxiety? (3)
1. Dopamine 2. Noradrenaline 3. Steroid hormones (cortisol),
122
What controls the flow of information entering the brain?
A central executive system,
123
What supports the central executive system? (2)
1. Phonological store 2. Silent rehearsal loop,
124
What allows us to hold on to images of objects for long enough to be able to manipulate them in your mind’s eye?
A visual sketchpad,
125
Where is the visual sketchpad?
Right hemisphere,
126
Which lobes is working memory largely located? (2)
1. Frontal lobe 2. Parietal lobe,
127
Where are the auditory parts of working-memory lateralised? (2)
1. Left frontal lobe 2. Parietal lobe,
128
What did working-memory co-evolve alongside?
Speech,
129
What is the function of perceptual representation?
This is used to store and later recognise things around us (e.g. identifying familiar people in newspaper cartoons),
130
What is semantic memory?
A vast storehouse of factual knowledge that we have all accumulated about the world.,
131
Why is sematic memory effective?
Facts are organised into categories,
132
Which parts of the brain are essential for skill-learning? (2)
1. Basal ganglia 2. Cerebellum,
133
Which parts of the brain are essential for emotional-learning?
Amygdala,
134
What is the function of episodic memory?
Used to keep track of personal experience.,
135
What is retrograde amnesia?
Memory loss of events 30 minutes earlier,
136
Which areas of the mid-brain are critical for memory? (3)
1. Mamillary bodies 2. Thalamus 3. Hippocampus,
137
What structures are important for episodic memory? (2)
1. Perirhinal cortex (PRH) 2. Hippocampus (HIPPO),
138
What is the function of the perirhinal cortex in episodic memory?
Mediates the sense of familiarity about the past,
139
What is the function of the hippocampus in episodic memory?
Encodes events and places,
140
What are place cells?
These are neurons in the hippocampus that fire action-potentials only when an animal explores a familiar place.,
141
Why do we believe that NMDA receptors are associated with place memory?
Learning about places is impaired when a drug that blocks NMDA receptors is applied to the hippocampus.,
142
How may we alleviate forgetfullness? (2)
Using drugs that: 1. Enhance NMDA or AMPA receptors 2. Stimulate the cascade of second-messenger signals,
143
What body signals does the brain interpret? (4)
1. Hormones 2. Nutrients 3. Inflammatory molecules 4. Information from peripheral nerves monitoring vital organs and sensations.,
144
What hormone causes the 'fight or flight' response?
Noradrenaline,
145
What is experienced during 'fight or flight'? (6)
1. Initial tingling sensation 2. Sweating 3. Heightened awareness 4. Rapid pulse rate 5. Higher blood pressure 6. General feelings of fear,
146
How does the body prepare for 'fight or flight'? (4)
1. Blood pressure shoots up 2. Heart rate accelerates (palpitations) 3. Receptors in the skin causing hairs to erect (goosebumps) 4. Disconcerting abdominal sensations in gut,
147
What is this called?
The hypothalamic-pituitary-adrenal (HPA) axis,
148
What makes up the HPA axis? (4)
1. Hypothalamus 2. Pituitary gland 3. Adrenal cortex 4. Hippocampus,
149
How are the glands in the HPA axis linked?
By a bloodstream highway,
150
What areas feed strong signals to the hypothalamus during stress?
Regions of the brainstem controlling sympathetic nervous responses (amygdala).,
151
Where can cortisol act? (2)
1. Hippocampus 2. Amygdala,
152
What is the net affect of cortisol when stressed (on the hippocampus and amygdala)?
The net effect is to turn on the amygdala - to allow learning of fear-related information; and to turn off the hippocampus,
153
Why does cortisol activate the amgydala more than the hippocampus?
To ensure that resources are not wasted on more complex but unnecessary aspects of learning.,
154
What cortisol receptors does the hippocampus have? (2)
1. Low MR 2. High GR,
155
How is the low MR receptor in the hippocampus activated?
By the normally circulating levels of cortisol in the bloodstream highway of the HPA axis.,
156
What happens in the hippocampus when cortisol begins to rise (in the morning)?
The high GR receptor becomes progressively more occupied. Activation of this receptor is sustained and the hippocampus is then shut down by a genetically controlled program.,
157
What are cortisol levels like in a severely depressed person?
Cortisol is over-produced so it is high,
158
How do anti-depressants work?
Normalise the overactive HPA axis (which is over-producing cortisol).,
159
How can the affect of severe-depression be decreased?
By blocking the production or action of cortisol,
160
What happens in terms of cortisol levels as in successful/unsuccessful ageing?
Cortisol levels are higher in unsuccessful than in successful ageing. This rise precedes the fall in mental abilities and the associated decline in the size of the hippocampus seen in brain scans.,
161
How do individuals who get more memory loss and other cognitive disorders with advancing years respond to stress?
They have excessive hormone responses to stress (not necessarily more stress but the greatest responses to stressors),
162
How may we be able to decrease memory loss as we age?
By exploiting antidepressant drugs that keep the HPA stress system under control.,
163
What cells does the immune system trigger? (3)
1. Macrophages 2. Acute phase proteins 3. Leucocytes,
164
What symptoms does the acute phase response have? (5)
1. Fever 2. Aches and pains 3. Sleepiness 4. Loss of appetite 5. Disinterest,
165
What does the immune response serve to do? (3)
1. Combat infection 2. Conserve energy 3. Aid repair,
166
How are neural signals detected by the brain?
Via sensory nerves,
167
How are humoral signals detected by the brain?
Via circulating molecules,
168
Which fibres specifically communicate neural signals (immune response)? (2)
1. C-fibres 2. Vagus nerve from the liver,
169
Why is the vagus nerve from the liver involved in neural signalling? (immune response)
Its a key site for production of acute phase proteins.,
170
Which proteins are involed in the main circulating signals to the brain (immune response)? (3)
1. Prostaglandins 2. Complement proteins 3. Cytokines,
171
What inhibits prostagladins?
Aspirin,
172
What are complement proteins?
A cascade of proteins important in killing invader cells,
173
Examples of cytokines (4)
1. Interferons 2. Interleukins 3. Tumour necrosis factors 4. Chemokines.,
174
What triggers cytokine production? (3)
1. Bacterial or viral products 2. Damage to cells 3. Threats to cell survival (toxins or low levels of oxygen),
175
How do cytokines stimulate inflammation? (3)
1. Swelling 2. Local changes in blood flow 3. The release of a second wave of inflammatory molecules.,
176
How do cytokines stimulate the immune system?
They act on the liver where they stimulate the acute phase proteins.,
177
What affects the effects of stress on the immune system?
It depends on the type of stress and how we respond,
178
What type of rhythm is the sleep-wake cycle?
Endogenous rhythm (circadian rhythm),
179
What controls locking in sleep and wakefulness to the day-night cycle?
A small group of cells in the hypothalamus just above the optic chiasm called the suprachiasmatic nucleus.,
180
What are the descrete stages of sleep called?
Slow-wave sleep,
181
What does REM sleep stand for?
Rapid-eye movement,
182
Why is it called REM sleep?
The EEG becomes like the waking state again and our eyes jerk back and forth beneath our closed eyelids.,
183
What symptoms occur during extreme lack of sleep? (4)
1. Difficulties with speech 2. Inability to concentrate 3. Lapses of memory 4. hallucinatory daydreaming,
184
What two genes are involved in our biological clock? (2)
1. PER 2. TIM,
185
What causes the local increase in cerebral blood flow in active areas?
The neurovascular link,
186
Who cannot recieve a PET scan? (2)
1. Children 2. Child-bearing women,
187
What techniques produces images from MRI scans?
Diffusion tensor imaging (DTI) (for images of the white matter tracts of fibres that connect brain regions).,
188
How does fMRI work?
This technique is based on the difference in magnetic properties of oxyhaemoglobin and deoxygenated haemoglobin in blood,
189
What does BOLD (the fMRI signal) in fMRI stand for?
Blood-Oxygenation-Level-Dependent signal,
190
How does event-related fMRI work?
Two very similar tasks are designed with one to be done immediately after the other. The first task should involve the brain process an experimenter is interested in and the other should not. The succession of brain images obtained are then subtracted from each other to yield a pixellated 2D image of what changes in activity are specifically associated with performing the critical brain process. These images are stacked up by the computer to yield an effective subtraction of the image in 3 dimensions.,
191
What does SPM stand for?
Statistical parametric mapping,
192
What is effective conntectivity?
How the neural activity of different brain regions interacts and correlates during complex tasks,
193
How can epileptic seizures be provoked? (5)
1. Tiredness 2. Missed meals 3. Low blood sugar 4. Alcohol 5. Flickering television screens.,
194
How can epilsepsy be treated? (2)
1. Drugs that dampen down abnormal seizure activity without damping down normal brain activity 2. It is possible to localise the source of their seizures and for a neurosurgeon to cut out this diseased brain tissue,
195
What happens when diseased tissue is removed in epileptics? (2)
1. Decrease in seizure frequency 2. Reduced risk of it spreading to brain tissue that is still unaffected.,
196
What is the most common cause of headaches?
Muscle tension,
197
What are the symptoms of a migraine? (3)
1. Feel sick 2. Find bright lights or loud noises discomforting 3. Experience a migrainous aura consisting of flashing lights or jagged lines.,
198
What treament exists for migraines?
Tripans that activate a subgroup of serotonin receptors (serotonin (5-HT) receptors),
199
What causes a weakness down one side of the body?
Stroke,
200
Why does a stroke cause weakness?
Interruption of the energy supply that the brain needs to function. Neurons and glia need fuel to work and to survive. That fuel is delivered through the four major blood vessels that supply the brain which can be blocked.,
201
What fuel does the brain need? (2)
1. Oxygen 2. Carbohydrate (glucose),
202
Why do brains need ATP?
This energy is necessary for driving the flow of charged ions that underlie the electrical activity of neurons. Most is used to fuel an enzyme called Sodium/Potassium ATPase which recharges the ionic gradients of sodium and potassium after an action potential has occurred.,
203
What happens in a transient ischaemic attack (TIA)?
The blood supply to a part of the brain fails and the supply of ATP is interrupted. Neurons cannot recharge their ionic gradients and so can no longer conduct action potentials,
204
What the most common cause of stroke?
Blood clots blocking vessels,
205
How can strokes be treated?
Tissue plasminogen activator (TPA) can break up the clot and restore blood flow.,
206
How else can a stroke be treated other than dealing with the clot directly?
Drugs that block neurotransmitters including glutamate that accumulate to toxic levels during a stroke. These drugs can either block glutamate receptors themselves or the intracellular signalling pathways that are turned on by glutamate. Many such drugs are in development. (Not yet working),
207
What are the symptoms of Huntington's disease?
Abnormal involuntary movements,
208
What are the symptoms of Parkinson's disease? (4)
1. Slowness 2. Stiffness 3. Tremors 4. Unsteadiness,
209
What causes Parkinson's disease?
Problems in genes coding for Parkin,
210
What are the symptoms of multiple sclerosis? (4)
1. Weakness 2. Numbness 3. Double vision 4. Poor balance,
211
What is slightly unusual about multiple sclerosis?
There is a cycle between periods of illness and remission every few weeks,
212
What causes multiple sclerosis?
Inflammation in the nervous system that flares up and then settles down again.,
213
Why is it hard to treat multiple sclerosis?
We do not yet know what triggers inflammation,
214
What is currently used to treat mild multiple sclerosis?
Steroids that dampen down the immune system.,
215
What is currently used to treat severe multiple sclerosis?
Permanently dampening down certain parts of the immune system with drugs like azathioprine or ß-interferon,
216
What disease occurs when the immune system attacks the junctions where nerves connect with muscles?
Myasthenia gravis,
217
What disease occurs when the immune system attacks the nerves as they emerge from the spinal cord?
Guillain Barré syndrome.,
218
What happens as Alzheimer's progesses? (3)
1. Brain cells die 2. The cortex thins 3. The ventricles enlarge.,
219
When is Alzheimer's confirmed?
Post-mortem when microscopic examination of the brain reveals the cell loss,
220
What can be observed in the post-mortem brain of someone with Alzheimers? (3)
1. Cell death 2. Deposition of an amyloid protein in scattered small degenerating amyloid plaques 3. A tangled mess of rod-like proteins that are normal constituents of brain cells (fibrillary tangles),
221
What mutations are believed to cause Alzheimers?
Mutations in genes that encode amyloid precursor protein (from which amyloid is made) and the presenilins (which encode enzymes that break the precursor protein down).,
222
What gene carries a big risk factor of Alzheimers?
A particular variation of the apolipoprotein E (apoE) gene designated apoE-4,
223
What environmental factors contribute to Alzheimers? (2)
1. Toxins 2. Traumatic brain injury,
224
Which transmitter is vulnerable to attack in Alzheimers?
Acetylcholine,
225
How are we currently 'treating' Alzheimers?
Drugs that boost the action of the remaining acetylcholine by blocking the effect of enzymes that normally destroy this neurotransmitter have a modest treatment effect in both animal models and some clinical cases.,
226
Symptoms of depression (4)
1. Disturbed sleep 2. Lowered appetite 3. Failing concentration and memory 4. Loss of interest in life,
227
How do antidepressants work?
Enhance the effects of neuromodulatory transmitters such as serotonin and noradrenaline,
228
How do anti-depressants protect against increased cortisol levels?
They promote the integrity of brain cells and increase the rate at which new neurons are produced in the hippocampus.,
229
What are the core symptoms of schizophrenia? (5)
1. Delusions 2. Hallucinations 3. Decline in cognitive ability 4. Decline in social interaction 5. Inability to work.,
230
What are delusions?
Abnormal beliefs – commonly bizarre ideas which are often persecutory in nature,
231
What are physical indicators of schizophrenia? (2)
1. Ventricles of the brain enlarge 2. The activity of the frontal lobes becomes impaired,
232
How can we reduce the symptoms of schizophrenia?
Using drugs that block dopamine receptors,
233
What are possible neuro causes of schizophrenia?
1. Abnormalities in the release of dopamine 2. Neurons have connected up during development may be abnormal 3. Neurotransmitter systems (glutamate) may be malfunctioning.,
