Neuro Lecture notes Flashcards
1
Q
What are the general functions of the left hemisphere?
A
Verbal, linguistic description, mathematical, sequential, analytical and direct link to conscious mind
2
Q
What are the general functions of the right hemisphere?
A
Almost non-verbal, musical, geometrical, spatial comprehension, temporal synthesis, possible link to conscious mind
3
Q
What are the four lobes of the brain?
A
Frontal
Temporal
Parietal
Occipital
4
Q
What is the central sulcus?
A
A division between the frontal and parietal lobe
5
Q
What is the lateral sulcus?
A
A division between the temporal and the frontal&parietal.
6
Q
What are the clinical signs of UMN lesion?
A
No change in aspect
Increased tone- spasticity
Pyramidal weakness
Increased reflexes
7
Q
What are the clinical signs of LMN lesion?
A
Muscular atrophy
Decreased tone
Focal weakness
8
Q
What are the four ventricles?
A
A pair of lateral ventricles
III
IV
9
Q
What are the cranial nerves?
A
Olfactory Tract Optic Occulomotor Trochlear Trigeminal Abducens Facial Vestibulochlear Glossopharyngeal Vagus Accessory Hypoglossal
10
Q
What are the arteries feeding into the Circle of Willis?
A
The internal carotid artery- a branch of the common carotid artery
The vertebral arteries
11
Q
What are the main branches of the Circle of Willis?
A
Anterior cerebral artery
Middle cerebral artery
Posterior cerebral artery
12
Q
What do the vertebral arteries merge to form?
A
The basilar artery
13
Q
What percentage of the brain is water?
A
80%
14
Q
What are the principles of dualism?
A
There are 2 kinds of “foundation”- mental and body
The mental cannot exist without the body; and the mind cannot think
15
Q
What is reductive physicalism?
A
Everything is applicable to the physical
16
Q
What is interactionism?
A
Entities have an effect on one another
17
Q
What is epiphenomenalism?
A
Physical affects mental but mental can’t effect physical
18
Q
What is mysterism?
A
Mind is only understood by reflection
19
Q
Why does the biomedical model predominate?
A
Power, economics, convenient, familiar, reductionism
20
Q
What is neurology?
A
Looking for abnormal brain chemistry, genetics, perfusion, structure
21
Q
What is psychiatry?
A
The functional consequences of distress and interaction with environment, interpersonal, psychological, social and cultural issues
22
Q
What are the functions of the dopamine pathways?
A
Reward, pleasure, motor function, compulsion, preservation
23
Q
What are the functions of the serotonin pathways?
A
Mood, memory processing, sleep, cognition
24
Q
Name 3 tests of executive function
A
Wisconsin card-sorting test
Proverb interpretation
Similarities test
25
How common is schizophrenia?
Affects roughly 1 in 100
26
What are the positive symptoms of schizophrenia?
Delusions, thought disorder, hallucinations
27
What are the negative symptoms of schizophrenia?
Withdrawal, can't carry on normal activities
28
What are the biological correlations of schizophrenia?
Brain Volume
Functional imaging
Dopamine theory
Genetic factors
29
What are the non-biological correlations of schizophrenia?
Urbanicity
Childhood trauma
Stress
30
Why may it be good to classify a mental disorder?
```
Public health issues e.g. allocation of resources
Facilitates meaningful communication
Feeling of being understood
Framework for research
Treatment and prognosis
```
31
Why may it be bad to classify a mental disorder?
Arbatory thresholds
Stigma and prejudice
Over simplification and reductionism
32
What are the two divisions of the vertebrate nervous system?
- CNS= within the skull and spine
| - PNS= Outside the skull and spine
33
What is the difference between the somatic and automatic nervous system?
The somatic is the part that interacts with the external environment, the automatic is the part that regulates the bodies internal environment: organs
34
What type of sensory input is received by the spinal cord?
Nervous or contact stimuli
35
What type of sensory input is received by the hind brain?
Sudden distal stimuli
36
What type of sensory input is received by the midbrain and hypothalamus?
Species specific threat stimuli
37
What type of sensory input is received by the thalamus?
Neural stimuli
38
What type of sensory input is received by the sensory cortex?
Complex neural stimuli
39
What type of sensory input is received by the hippocampus and septum?
Context
40
What type of sensory input is recieved by the frontal cortex?
Cognitive analysis
41
What type of output is produced by the frontal cortex?
Response supression
42
What type of output is produced by the amygdala?
Conditioned, emotional response
43
What type of output is produced by the midbrain and hypothalamus?
Species-specific response
44
What type of output is produced by the hind brain?
"Startle" response
45
What type of output is produced by the spinal cord?
Reflexive withdrawal
46
Is the dorsal root afferent or efferent?
Afferent
47
Is the ventral root afferent or efferent?
Efferent
48
What is the role of the medulla?
Low level sensorimotor control
| Same with vital functions, sleep, motor
49
What is the role of the pons?
Relay from cortex and midbrain to cerebellum
50
What is the role of the cerebellum?
Co-ordinates movement and balance. Mainly fine coordinated voluntary movement
51
What is the difference between the superior colliculus and inferior colliculus?
The superior is sensitive to sensory change- orienting/defence movements
The inferior is similar but for auditory events
52
What are the three components to the tegmentum?
The periaquidal gray
The red nucleus
The substantia Nigra
53
What are the roles of the periaquiductal gray?
Role in defence, pain and reproduction
54
What are the roles of the red nucleus?
Target of cortex and cerebellum, project to spinal cord. Role in pre cortical motor control
55
What are the roles of the specific nuclei within the thalamus?
Relay signals to the cortex/limbic system for all sensations (Exc smell)
56
What are the roles of the non-specific nuclei within the thalamus?
Role in regulating state of sleep, wakefullness, and levels of arousal. Important relays from basal ganglia and cerebellum back to cortex
57
What is the role of the hypothalamus?
Regulates pituitary and role in hormonal role of motivated behaviour- co-ordinates drive related behaviour
58
What are the structures contained within the limbic system?
```
Amygdala
Mammillary body
Hippocampus
Septum
Cingulate Gyrus
Fornix
```
59
What is the role of the amygdala?
Associating sensory stimuli with emotion. Responsible for fear.
60
What is the role of the mammillary body?
Formation of recollective memory
61
What is the role of the hippocampus?
Long term and spatial memory. Critical for episodic memory. Essential for the construction of mental images. Has a vital role in short term memory.
62
What is the role of the septum?
Defense and aggression
63
What is the role of the cingulate gyrus?
Linking behavioural outcomes to motivation
64
What is the role of the fornix?
Carrying signals from the hippocampus to mammillary bodies and septal nucleus
65
What is the role of the precentral gyrus?
Motor instructions
66
What is the role of the primary motor cortex?
Contains many cells giving origin to the descending motor pathways
67
What is the role of the premotor and supplementary motor areas?
Higher level motor plans and initiation of voluntary movements?
68
Where are the precentral gyrus, primary motor cortex, premotor and supplemetary motor areas?
Within the frontal lobe
69
Where is the post-central gyrus and primary somatosensory cortex?
Within the parietal lobe
70
What is the role of the primary somatosensory cortex?
Body and head's position in space
| Permits complicated spacio-temporal predictions
71
Where are the primary auditory complex and inferotemporal cortex found?
Within the temporal lobe
72
What is the role of the inferotemporal cortex?
Recognition of faces and objects
73
Where is the visual corticies?
Within the occipital lobe
74
What is the dorsal stream?
Vision for movement
75
What is the ventral stream?
Vision for identification
76
What are the levels of description within the research of neuroscience?
```
Psychological
Systems
Microcircuit
Neuronal
Intracellular
Molecular
```
77
What are some of the possible constraints of research within neuroscience?
Expertise, facilities, time, money, ethics
78
What is a contrast X-ray?
An x-ray, but using an injected substance. This provides image contrast between intravascular and extravascular components
79
What are the different techniques that can be used successfully on humans within neuroscience?
```
Contrast X-ray
MRI
fMRI
PET
EEG
MEG
TMS&TDCS
```
80
What are the different invasive methods that can be used in animal models of neuroscience research?
Direct measurement of brain activity
Determining connectivity between structures
Distrupting connectivity between structures to determine effects on circuit function
Leison specific structures to inform us about its function
Pharmacological research
Genetic manipulations
Optogenetics
81
What is fMRI?
Altered MRI to be sensitive to oxygenated or deoxygenated blood. Blood changes due to brain activity.
82
How can PET scan be used in neuroscience?
Use a contrast agent that is specific to a biological process. The chemical will bind to the target. Attach a radioisotope to a positron emitter. Inject the tracer then image. Poor spatial and temporal resolution.
83
How can an EEG be used in neuroscience?
Using electrodes on scalp, can analyse regional brain activity. Good temporal resolution and bad spatial resolution. Analysis is complex. Can be used to look at brains response to stimuli.
84
When are neurons formed?
Mainly, but not exclusively, formed during brain development
85
What are the two types of synapse? Which is more common?
Chemical- majority
| Electrical- Less abundant
86
Briefly describe how a synapse works
Nerve travels down axon, causing depolarisation. This opens voltage-gated Ca2+. Neurotransmitter is released into synaptic cleft and attaches to receptor on the post synaptic membrane.
87
What is the importance of neural plasticity?
It is the basis of learning and memory
88
What can change between neurons? (heterogeneity)
Size
Morphology
Electrical properties
Neurotransmitters
89
What is the difference between upper motor neurons and striatal interneurons?
Upper motor neurons- large, excitatory, glutametergic, long projection pyramidal cells.
Striatal interneuron- small, inhibatory, GABAergic
90
Describe olgiodendrocytes
Myelinating cells of the CNS
Unique to vertebrates
Myelin insulates axon segments, enables rapid nerve conduction
Myelin sheath segments interrupted by nodes of ranvier- saltatory conduction
Provides metabolic support for axons
91
What is the myelin sheath?
Formed by wrapping of axons by olgiodendrocyte processes. Highly compacted- 70% lipid, 30% protein.
Myelin specific proteins e.g. MBP, involved in compaction.
92
Describe microglia
Resident immune cells of the CNS. Originate from yolk sac progenitors that migrate into CNS
"Resting" state- highly ramified, motile processes that survey the environment. Upon activation, they retract their processes, becoming "ameoboid" and motile. Proliferate at sites of injury- phagocytic.
93
What are the functions of microglia?
Immune surveillance
Phagocytosis- debris/microbes
Synaptic plasticity- pruning
94
What are astrocytes?
Star-like cells. Most numerous glial cells in the CNS. Highly heterogenous. Common "marker" glial fibrillary acidic protein.
95
What are the functions of astrocytes?
```
Developmental
Structural- define brain architecture
Envelope synapses
Homeostatic- buffer K+, glutamate etc
Metabolic support
Disease- gliosis/astrocytosis
Neurovascular coupling
```
96
What are the features of the blood-brain barrier?
```
Endothelial tight junctions
Astrocyte end feet
Pericytes
Lacks fenestrations
Specific transporters
```
97
What is the choroid plexus formed from?
Modified ependymal cells
98
What is the main site of CSF production?
The choroid plexus, mainly within the lateral ventricles
99
What are the functions of the frontal lobe?
Voluntary movement on opposite side of body
Frontal lobe of dominant area controls speech (Brocas area) and writing
Intellectual functioning, thought processes, reasoning and memory
100
What are the functions of the parietal lobe?
Recieves and interprets sensations, including pain, touch, pressure, size and shape, and body-part awareness
101
What are the functions of the temporal lobe?
Understanding the spoken word, sounds as well as memory and emotion
102
What are the functions of the occipital lobe?
Understanding visual images and meaning of written words
103
How does a neuron stain under H&E?
The haemotoxylin stains the nucleic acids blue, and the eosin stains the proteins red
104
What are the basic components of neurons?
Dendrites
Cell body/Soma
Axon
Presynaptic terminals
105
What are the symptoms of multiple sclerosis?
```
Eye movements are controlled
Slurred speech
Paralysis
Tremor
Loss of co-ordination
Sensory weakness
```
106
What is diffusion?
The force driving molecules to move to areas of lower concentration
107
What is the ratio of sodium ions to potassium ions pumped by the sodium-potassium pump?
Three sodium ions for every two potassium ions
108
What is temporal summation?
One axon firing many times
109
What is spatial summation?
Lots of axons firing once
110
What are the symptoms of novichok poisoning?
```
Muscle convulsions
Paralysis
Heart Failure
Asphyxiation
Constricted Pupils
Vomiting
```
111
What are the five fundamental processes of synaptic transmission?
1. Manufacture
2. Storage
3. Release
4. Receptor activation
5. Inactivation
112
How long do fast neurotransmitters last and give some examples
Short lasting
| Acetyl choline, glutamate, gamma-aminobutyric acid
113
How long do slow neurotransmitters last and give some examples
Slow acting
| Dopamine, Noradrenaline, Serotonin
114
What chemicals affect ACh?
Cigarettes
Poison Arrows
Spider Toxins
Nerve gas
115
What chemicals affect Noradrenaline?
Antidepressants (imipramine blocks reuptake)
Antidepressants (MAO inhibitors block break-down)
Stimulants
116
What chemicals affect dopamine?
Antipsychotic drugs
Stimulants
Antiparkinsons drugs
117
What chemicals affect serotonin?
Antidepressant drugs
Hallucinogens
Ecstacy
118
What are the side effects of GABA?
Anti anxiety
Anti convulsant
Anaesthetic
119
What are the side affects of L-DOPA?
Anti-psychotic
| Causes Parkinsons symptoms at high doses
120
Why may CT Scans be used instead of MRI scans to analyse the brain?
Better for bone and calcification
Quicker scan times than MRI
MRI can be noisy and claustrophobic
121
Why may MRI scans be used instead of CT scans to analyse the brain?
CT scans require ionated contrast media= allergic reaction? (MRI do not)
CT scans use a high dose of X-rays
MRI provides excellent anatomical detail
122
What are the two muscles that control lid position?
```
Orbicularis oculi (Closes lid, controlled by CN VII- facial)
Levator palpebrae muscle (elevates upper lid, sympathetic nervous supply)
```
123
Where are the meibomian glands and why are they important?
There is a series of openings on the lid. The glands themselves lie in the tarsal plate. They secrete the early components of the tear film
124
What is the function of the conjunctiva?
Acts as a barrier
| Produces mucin from the goblet cells and aqueous part of tear film from the accessory lacrimal glands
125
What are the layers of the tear film and roles of each?
Anterior lipid layer- stabilizes tear film and reduces evaporation
Middle aqueous layer- Contain antibodies, enzymes and vitamin C
Deep mucin layer- Allows aqueous layer to spread over relatively hydrophobic cornea apithelial cells
126
What are the general functions of the tear film?
Protects
| Provides smooth, clear, anterior refracting surface for cornea
127
Where are tears produced and what is their function?
Produced by main lacrimal gland in response to stimuli
| Acts as a protective agent when the eye is irritated and helps wash out foreign bodies
128
What is the nervous supply to the cornea?
Opthalmic divison of the trigeminal nerve (CN V)
129
What are the layers of the cornea?
Epithelium (anterior)
Stroma (Middle)
Endothelium (Posterior)
130
Describe the stroma of the cornea
Regular lamina of collagen fibres, dehydrated, no blood vessels, thickest part
131
What is the function of the fluid pump in the endothelium of the cornea?
To counteract the tendancy of the cornea to become cloudy
132
Where does the cornea receive nutrients from?
No vessels (transparent) so receives nutrients from the tear film anteriorly and aqueous humour posteriorly
133
What is the site of the trabecular meshwork?
The anterior chamber angle
134
What are the muscles of the iris and their nervous supply?
```
Dilator muscle (sympathetic branch of nerves to eye, has alpha receptors)
Sphincter muscles (parasympathetic fibres within CN III, contains muscularinic receptors)
```
135
What is the function of the iris?
To control light entry
136
What is the function of the lens?
To focus light onto the retina. Also can alter shape thus increasing or decreasing the refracting power of the eye
137
What is the function of the ciliary body?
Pars plicata: ciliary processes that secrete aqueous humour. Enhanced by folds to increase SA
Pars plana: Thin part which merges with choroid
138
What is the innervation of the ciliary muscle?
Parasympathetic fibres in CN III
139
Where is the vitreous humour found?
Between the posterior lens and retina
140
What does the vitreous humour consist of?
A scaffold of collagen fibres and large, negatively charged molecules.
141
What is the retina made up of?
Outer layer photoreceptors
1st and 2nd order neurons (bipolar and ganglion cells)
Interneurons (amacrine and horizontal cells)
Neuroglial cells
Pigment cells
Supporting membranes
142
What tools would be used to view the surface of the retina?
An opthalmoscope
143
Describe the macula
3mm Central area temporal to optic disc
Thickest part of retina
Highest concentrations of cones
Yellowish pigment
144
Describe the fovea
```
Central zone of macula (concave profile)
Thinnest part of retina
Just consists of cones
No retinal blood vessels
Best visual acuity
```
145
What is the role of the choroid?
Removes heat from retina
146
What is the diameter of the optic disc?
1.5mm
147
What is the general colour of the optic disc and why?
Pink as there are lots of capillaries
148
Where is the blind spot?
In the optic disc
149
What is the sclera?
Tough, protective outer layer of globe. Perforated posteriorly by optic nerve. Openings for vessels. Irregularly arranged collagen fibres for strength. Covered in a thin, vascular episclera
150
What causes the pupil diametre to change?
- Changes in light intensity
- Proximity of object
- State of arousal
151
What are the causes of abnormal light response?
```
Afferent= Optic nerve disease, severe retinal disease
Efferent= Third nerve palsy, adie pupil, damage to iris, atropine
```
152
What is the dark response?
Active dilation by sympathetic stimulation of dilator muscle as well as inhibition of sphincter muscle
153
What is the ciliospinal reflex?
Painful stimulation of neck causes pupil dilation on the same side
154
Why is there a high intraocular pressure?
To allow the eye to move without deforming
155
What tool is used to measure intraocular pressure?
Tonometer
156
What is glaucoma and hypotony?
Glaucoma- high intraocular pressure
| Hypotony- Low intracular pressure
157
What are the branches of the opthalmic artery and what do they supply?
Central retinal artery- inner retina
Ciliary arteries- outer retina and anterior part of globe
Additional Branches
158
Are the retinal capillaries or choroidal capillaries leaky?
Choroidal
159
What are the two visual systems of each eye?
Scotopic (monochromatic, low light conditions, function of rods)
Photopic (chromatic, bright light conditions, function of cones)
160
What is the trichromatic colour theory?
There are three types of cones and they respond differently to wavelengths of light. The maximum response roughly matches red, green and blue light. Different cones response to different wavelengths are perceived as colour.
161
What factors limit visual fields?
Extent of retinal photoreceptors
| Facial anatomy
162
What are the dimensions of the visual fields?
Nasally 60 degrees
Temporally 100 degrees
Superiorly 70 degrees
Inferiorly 80 degrees
163
What is myopia and hyperopia?
Myopia- the eye is too long, short sightedness
| Hyperopia- The eye is too short, long sightedness
164
What happens when images are brought closer to the eye?
Near reflex
- The lens increases its refracting power
- The eyes converge
- The pupils constrict
165
What tool is used to measure visual acuity?
The snellen chart
166
What is a strabismus?
A squint
167
What are the clinical features of a retinal problem?
- Total loss of vision in one eye
- Loss of part of visual field in one eye that mirrors area damage
- Loss of the upper or lower half of field of vision
- Loss of centre of vision; central scotoma
- Tunnel vision
168
What are the clinical features of an optic nerve problem?
- Enlarged blind spot
- Loss of centre of vision
- Loss of vision in arc shape
- Tunnel vision
169
What are the clinical features of an optic chiasm problem?
-Loss of temporal field of vision in both eyes; bitemporal hemianopia
170
What are the clinical features of an optic tract problem?
- Loss of field of vision on the contralateral side to the side of the problem. Problem is homonymous (temporal in one eye and nasal in other), affecting up to 1/2 of the visual field and greater in one eye than the other
171
What are the clinical features of an optic radiation problem?
- Contralateral homonymous field defects that are either predominantly in the inferior visual field (parietal lobe lesion), or the superior visual field (temporal lobe lesion). The effects are similar in both eyes.
172
What are the clinical features of a visual cortex problem?
- Highly congruous, contralateral, homonymous hemianopia
- As they are often vascular and the occipital lobe has a blood supply from the middle and posterior cerebral arteries, the central visual field is often spared.
173
In what order should one clinically examine the eye muscles?
1. Lateral and medial rectus
2. Superior and inferior rectus
3. Inferior and superior oblique
174
How should you examine lateral and medial rectus?
Sit in front of the patient. Place a finger at eye level, at about an arms length from their face and move it right to left. Observe each eye in turn.
175
How should you examine superior and inferior rectus?
Sit in front of the patient. Get the patient to look 23 degrees to the side. Place a finger about an arms length from their face and move it up and down. Observe each eye in turn.
176
How should you examine inferior and superior oblique?
Sit in front of the patient. Place a finger at eye level at about an arms length from their face and out to the side. Move the finger up and down. Repeat on both sides.
177
What are the three semi-circular canals?
Anterior, posterior and lateral
178
Why does dizziness occur?
When the semi-circular canals send signals to the brain when there is no movement.
Physiological cause= after spinning
Pathological cause= Labarynthitis
179
Describe the vestibulo-ocular reflex test
Lie patient on side
Poor ice-cold water in the ear. This creates a convection current in the canal.
This sends a signal to the brian
The eyes should slowly move towards the cold water, then jump back to normal position.
180
Define sensation
The mental process that results from the immediate external stimulation
181
Define perception
The ability to become aware of something, or understand something following sensory stimulation
182
What are the 5 types of perception?
Tactile, gustatory, visual, auditory, olfactory
183
What is the perceptual set?
```
The psychological factors that determine how you perceive your environment.
Context
Culture
Expectations
Mood and motivation
```
184
What is bottom up processing and top down processing?
Broadly speaking, bottom up processing is sensation, and top down processing is perception
185
What is a hallucination?
Experiences involving the apparent perception of something not present.
An error in top down processing. They are unique in individuals due to their different perceptual set.
186
What is the normal human hearing range?
20 Hz- 20 KHz
187
Describe the Pinna
A cartilaginous structure. It is formed from pharyngeal arches 1 and 2 (6x hillocks of his).
188
What is the role of the outer ear?
Direct sound waves towards the ear canal.
189
How much of the outer ear canal is cartilage and how much is bone?
1/3 cartilage, 2/3 bone
190
What is the pars flaccida and pars tensa?
The pars flaccida is the top 1/3 of the tympanic membrane
| The pars tensa is the bottom 1/3 of the tympanic membrane
191
What muscles are within the middle ear, and what bone are they attached to?
```
Tensor Tympani (malleus)
Stapedius (Stapes)
```
192
What is the role of the middle ear?
To amplify air-bone sound vibration
193
What are the roles of the middle ear muscles?
Protection of inner ear from acoustic trauma
Stiffens the ossicular chain
Stapedius is stimulated acoustically
25 ms reaction time in man
Tensor tympany- Voluntary and involuntary control
Chewing
194
What are the roles of the eustachian tube?
Ventilation of the middle ear space, keeping pressure equal
| Drainage of secretions
195
Describe the inner ear
A set of fluid filled sacs, encased in bone
| Innervated by the vestibulocochlear nerve
196
What is the role of the labyrinth?
Balance
197
How many spirals are formed in the cochlear?
2.7
198
What are the two openings of the cochlear?
Round window and oval window
199
What are the three compartments of the cochlear?
Salca tympani
Salca media
Salca vestibuli
200
What are the endolymph and perilymph? Where are they found?
Endolymph- High K+ solution , found in scala media
| Perilymph- like ECF and CSF, Na+ rich, found in Scala tympani and scala vestibuli
201
What is the difference between the basilar membrane base and apex?
```
The base (tympanic membrane) is narrow and stiff. It detects high frequencies.
The apex is wide and floppy. It detects low frequencies.
```
202
What are the roles of the inner and outer hair cells?
```
Inner= mechanical transducens
Outer= Fine tuning
```
203
How does movement of the stereocilia cause release of neurotransmitter?
Movement of sterocilia
Rapid response required
Mechanically gated K+ channels are opened, causing depolarization
This results in opening of voltage-gated Ca2+ channels
Release of neurotransmitter
204
What are the parts of the central auditory pathway? (ECOLI)
```
Eighth nerve
Cochlea
Olive
Lateral lemniscus
Inferior colliculus
```
205
What is conductive hearing loss?
A defective outer or middle ear
206
What is sensorineural hearing loss?
A defective inner ear
207
What are the latin names of the midbrain, forebrain and hindbrain?
Forebrain- Prosencephalon
Midbrain- Mesencephalon
Hindbrain- Rhombencephalon
208
What are the parts of the prosencephalon?
Telencephalon (hemispheres and basal ganglia)
| Diencephalon (thalamus, subthalamus, hypothalamus, epithalamus)
209
Define psychological stress
The state of mental or emotional strain or tension resulting from adverse or demanding circumstances
210
What is eustress?
Positive stress which is beneficial and motivating. Typically the experience of striving for a goal which is within reach,
211
What is distress?
Negative stress which is damaging and harmful. Typically when a challenge is not resolved by coping or adaptation.
212
What is acute stress?
Short lived response to a novel situation experienced by the body as a danger.
213
What is chronic stress?
Arises from repeated or continued exposure to threatening or dangerous situation, especially those that cannot be controlled.
214
What are some causes of chronic stress?
```
Physical illness
Physical or sexual abuse
Poverty
Unemployment
Bullying
Caregiving
```
215
What are the 3 phases of Selye's syndrome?
Alarm- Threat is realised
Adaptation- Body engages defense response
Exhaustion- Body runs out of defensive responses
216
What are the five elements of the human stress response?
```
Biochemical
Physiological
Behavioural
Cognitive
Emotional
```
217
Describe the sympathomedullary path of the stress response
Hypothalamus activates adrenal medulla
Adrenal medulla releases adrenaline and noradrenaline into bloodstream
Body prepares for fight or flight. Adrenaline and noradrenaline reinforces the pattern of sympathetic activation
Energy
218
Describe the pituitary-adrenal system of the stress response
Higher brain centre activates hypothalamus
Hypothalamus releases corticotrophin
Pituitary gland releases adrenocorticotrophic
Adrenal cortex releases corticosteroids
Corticosteroids causes changes- liver releases energy and immune system is suppressed
219
What is the biochemical stress respose?
Glucocorticoids (Cortisol)
Catecholamines (Adrenaline and noradrenaline)
Inflammation and immune response
220
What are the immediate physiological stress responses?
```
Rapid breathing
Increased blood flow
Increase HR and BP
Tense muscles
Glucose release
RBC discharged from spleen
Dry mouth
Sweating
```
221
What are the later physiological stress responses?
```
Headache
Chest pain
Stomach ache
Low energy
Loss of labido
Colds and infections
```
222
What are the behavioural stress responses?
```
Easily startled
Change in appetite
Change in weight
Procrastination or avoiding responsibilities
Alcohol, drugs
Nail biting, fidgeting
Sleep disturbances
Withdrawal
```
223
What are the cognitive stress responses?
```
Worrying
Racing thoughts
Forgetfulness
Inability to focus
Poor judgement
Pessimistic
Learning
```
224
What are the emotional stress responses?
```
Depression and sadness
Tearfulness
Mood swings
Irritibility
Restlessness
Aggression
Low self-esteem
Boredom
Overwhelmed
Rumination, anticipation and avoidance
```
225
What is allostasis?
It refers to how multiple and complex systems adapt collectively in changing environments through dynamic change
226
What are the symptoms of PTSD?
```
Vivid flashbacks and nightmares
Sweating
Nausea
Trembling
Hyper vigilance
Insomnia
Irritibility
```
227
Define natural selection
The differential survival and reproduction of individuals due to differences in phenotype
228
What is evolutionary medicine?
The application of modern evolutionary theory to understand health and disease. It considers a species perspective with related interests to evolutionary psychology and medicine.
229
What are tinbergen's questions?
Mechanism- How does this behavior occur in an individual?
Development- How does this behavior arise in an individual
Evolution- How does this behavior arise in the species
Adaptive value- Why is this behaviour adaptive for the species
230
What is compassion focussed therapy?
Therapy rooting in evolutionary and neuroscience approach to physiological processes. CFT is aimed at facilitating development of soothing and social safeness system
231
What are the three types of retinal ganglion cells and what does each do?
Parvocellular- Low contrast, High linear spatial resolution layers 1 and 2
Konicocellular- Blue-yellow colour oppenency, layers 3 to 6
Magnocellular- High contrast, low resolution, motion detection, colour blind, interspersed
232
What does the brain use for analysing depth perception?
```
Familiar size
Occlusion
Linear perspective
Size perspective
Shadows and illumination
Motion Parallax
```
233
What are the symptoms of a lesion affecting the middle temporal visual area?
Akinetopsia (loss of motion vision)
| Impaired saccades
234
What are the three types of saccades?
Spontaneous
Reflexive
Voluntary
235
What is the function of a vestibular eye movement?
Holds eye steady on retina during brief head rotations or translations
236
What is the function of the visual fixation eye movements?
Holds the image of a stationary object on the fovea by minimising ocular drifts
237
What is the function of the optokinetic eye movement?
Holds images steady on the retina during sustained head rotation
238
What is the function of the smooth pursuit eye movement?
Holds the image of a small moving target on the fovea; or holds the image of a small near target on the retina during linear self-motion
239
What is the function of a nystagmus quick phase eye movement?
Reset the eyes during prolonged rotation and direct gaze towards the oncoming visual scene
240
What is the function of a saccade eye movement?
Bring images of objects of interest onto fovea
241
What is the function of a vergence eye movement?
Moves the eyes in opposite directions so that images of a single object are placed or held simultaneously on the fovea of each eye
242
Where do pyramidal motor pathways originate?
The cerebral cortex
243
Briefly describe the difference between the lateral and anterior corticospinal tract
Lateral- crosses over at medulla, terminates at ventral horn synapsing with lower motor neurons. Carries limb information. Roughly 90% of pyramidal fibres are lateral
Anterior- Remains ipsilateral, terminates at ventral horn of cervical and upper thoracic segments. Carries info about axial muscles. Roughly 10% of pyramidal fibres.
244
Describe the corticobulbar pyramidal tract
Supplies musculature of the head and neck
Terminates at the brainstem on the motor nuclei of the cranial nerves
Lower motor neurons carry motor signals to muscles of face and neck
245
Where do extrapyramidal motor tracts originate?
The brain stem
246
What are the four extrapyamidal tracts and each of their actions?
Tectospinal- head turning in response to visual stimuli
Rubrospinal- Assists in motor function
Vestibulospinal- Muscle tone and posture
Reticulospinal- Spinal reflexes
247
What are the main differences between a UMN lesion and a LMN lesion?
UMN- No muscle wasting, hypertonia, paralysis affects movements of groups of muscles, hypereflexia, absent fasciculation, present babinski sign and clasp-knife reflex
LMN- Atrophy, hypotonia, flaccid paralysis, hyporeflexia, present fasciculation, absent babinski sign and clasp-knife reflex
248
What are the 12 cranial nerves?
```
Olfactory
Optic
Occulomotor
Trochlear
Trigeminal
Abducens
Facial
Vestibulocochlear
Glossopharyngeal
Vagus
Accessory
Hypoglossal
```
249
Which of the cranial nerves have parasympathetic innervations?
3, 7, 9, 10
250
Which cranial nerves have special sensory innervation?
```
Olfactory (smell)
Optic (Vision)
Facial (Taste to anterior 2/3 of tongue)
Vestibulocochlear (Auditory)
Glossopharyngeal (Taste to posterior 1/3 of tonuge)
Vagus (Taste to epiglottis)
```
251
Where does each cranial nerve exit the skull?
```
1- Cribriform plate
2- Optic Canal
3- Superior orbital fissure
4- Superior orbital fissure
5- V1 - Superior orbital fissure
V2- Foramen rotundum
V3- Foramen Ovale
6- Superior orbital fissure
7- Internal acoustic meatus then stylomastoid foramen
8- Internal acoustic meatus
9- Jugular foramen
10- Jugular foramen
11- Jugular foramen
12- Hypoglossal canal
```
252
What are the tests for each cranial nerve?
1- Smell test
2- Snellen chart, Fundoscopy, cover aspects of eye
3,4,6- H eye test
5- Clench teeth, test face sensation
7- Inspect face for asymmetry during facial expression, taste test
8- Whisper number into patients ear
9- Taste test
10- Analyse patients voice, gag reflex test
11- Turn head against resistance, shrug shoulders
12- Protrude tongue, inspect for asymmetry
253
Cranial nerves: Is the optic nerve sensory function, motor function, or both?
2- Sensory (special sense of vision)
254
Cranial nerves: Is the opthalmic nerve sensory function, motor function, or both?
1- Sensory (special sense of smell)
255
Cranial nerves: Is the occulomotor nerve sensory function, motor function, or both?
3- Motor ( Movement of eye muscles)
| Parasympathetic (pupillary reflex)
256
Cranial nerves: Is the trochlear nerve sensory function, motor function, or both?
4- Motor (Movement of superior oblique)
257
Cranial nerves: Is the trigeminal nerve sensory function, motor function, or both?
5- Sensory ( Face and mouth)
| Motor (muscles of mastication by V3)
258
Cranial nerves: Is the abducens nerve sensory function, motor function, or both?
6- Motor (Movement of lateral rectus)
259
Cranial nerves: Is the facial nerve sensory function, motor function, or both?
7- Motor ( Muscles of facial expression and stapedius)
Parasympathetic (Lacrimal gland and submandibular/sublingual glands)
Special sensory (Taste to anterior 2/3 of tongue)
260
Cranial nerves: Is the vestibulocochlear nerve sensory function, motor function, or both?
8- Special sensory (Hearing and balance)
261
Cranial nerves: Is the glossopharyngeal nerve sensory function, motor function, or both?
9- Motor (Stylopharyngeus muscle)
Sensory (Skin of external ear, posterior 1/3 of tongue, carotid body, carotid sinus, eustachian tube)
Special sensory (Taste to posterior 1/3 of tongue)
Parasympathetic (Parotid gland)
262
Cranial nerves: Is the vagus nerve sensory function, motor function, or both?
```
10- Motor (Muscles of pharynx and larynx)
Parasympathetic (Viscera of abdomen and thoracic wall)
Sensory (external ear)
Special sensory (Epiglottis)
```
263
Cranial nerves: Is the accessory nerve sensory function, motor function, or both?
11- Motor (Sternocleidomastoid, trapezius)
264
Cranial nerves: Is the hypoglossal nerve sensory function, motor function, or both?
12- Motor (Intrinsic and extrinsic muscles of the tongue)
265
Define pain
Unpleasent sensory and emotion associated with actual or potential tissue damage or described in terms of such damage
266
Define nociceptive pain
Actual or threatened damage to non-neural tissue and is due to activation of nociceptors
267
Define neuropathic pain
Pain caused by a lesion or disease of the somatosensory nervous system
268
Define allodynia
Pain due to a stimulus that does not normally provoke pain
269
Define dysethesia
An unpleasent abnormal sensation, can be spontaneous or provoked
270
Define hyperalgesia
Increased pain from a stimulus that normally provokes pain
271
What is the difference between acute and chronic pain?
Acute = less than 12 weeks
| Chronic pain= Continuous pain for more than 12 weeks. Pain persisting beyond tissue healing time
272
What are the roles of the insular cortex?
Perception, motor control, self awareness, interpersonal experience
Plays a role in addiction
Degree of pain judged here
273
What are the causes of cancer pain?
1. Pain directly from tumour
2. Cancer therapy pain
3. Pain unrelated to the cancer
274
Describe the pain pathway
1. Initial injury activates nociceptors peripherally
2. Nociceptors begin to fire (inflammatory soup)
3. The impulse within the afferent neuron rapidly goes into the dorsal root ganglion
4. Here, it projects into the 2nd order neuron which travels on the ipsilateral side into the spinolthalamic tract
5. This travels up spinal cord to the thalamus and in the thalamus it projects another impulse into the sensory cortex
275
What are the symptoms of depression?
General- Low mood, anhedonia, low energy
Biological- Poor sleep, Poor appetite, Reduced labido, Poor concentration
Cognitive- Worthlessness, guilt, hopelessness, suicidal thoughts
276
Describe the HPA axis
1. In response to stress, the hypothalamus causes release of corticotropin releasing hormone
2. The anterior pituitary detects this and secretes anderrinotopic hormone
3. The adrenal cortex thus releases cortisone, which acts as a negative feedback loop to inhibit the hypothalamus and anterior pituitary
277
How does the volume of the brain alter in depressed patients?
Large vol loss of dorsolateral prefrontal cortex
| Reduced hippocampus size
278
What affect do antidepressants have on the brain?
Increased GR expression thus regulating HPA activity
Increased neurogenesis
Increased BDNF synthesis, increasing the number of synapses
279
What is the default mode network?
The resting state of the brain- daydreaming and internal flow of consciousness. Includes autobiographical details, self reference and thinking about others.
280
What is a motor unit?
A single alpha motor neuron and all the muscle fibres it innervates. Different motor neurons innervate different numbers of muscle fibres. Fewer fibres means greater movement resolution.
281
What is the motor pool?
All the lower motor neurons that innervate a single muscle. They contain both alpha and gamma motor neurons. They are of ten arranged in a rod-like shape within the ventral horn of the spinal column.
282
What are the two ways in which cell bodies in the ventral horn can be activated?
1. Sensory information from the muscle
| 2. Descending information from the brain
283
Where is the golgi tendon organs and what do they detect?
They are located within the tendon. Mostly, it is sending sensory information to the brain via the spinal cord about the tension in the muscle/ the muscle's force.
284
What is the innervation of intrafusal and extrafusal fibres?
Intrafusal- gamma motor neurons
| Extrafusal- Alpha motor neurons
285
Where are muscle spindles and what do they detect?
They are embedded within most muscles and are composed of intrafusal fibres. They detect stretch regardless of current muscle length.
286
What are the role of sensory fibres within muscle spindle feedback?
They coil around intrafusal fibres and are innervated by gamma motor neurons. They keep the intrafusal fibres set at a length that optimises muscle strength detection.
287
What is the size principle?
Units are recruited in order of size. Fine control is typically required at lower forces.
288
What are the numbers of muscle fibre variants?
1. Level of control
| 2. Strength
289
What are the three fibre types?
Slow
Fast fatigue resistant
Fast fatiguable
290
What is the output of the basal ganglia?
Mainly inhibitory information- travels to the cortex via the thalamus
291
What is centralised selection?
There are multiple command systems that are spatially distributed. They process in parallel and all act through a final common motor path. Centralised selection decides which pathway to choose. It inhibits all other pathways to allow the chosen pathway through. It is done by the basal ganglia.
292
What are the symptoms of cerebellar damage?
```
DANISH
D- Dysdiodochokinesia
A- Ataxia
N- Nystagmus
I- Intention Tremor
S- Slurred speech
H- Hypotonia
```
293
What is a commisure?
A tract connecting one hemisphere to the other
294
What is asynergia?
Loss of co-ordination of motor movement
295
What is nystagmus?
Abnormal eye movements
296
How many layers are there of neocortex?
6
297
What are the inputs/projections of each layer of neocortex?
```
1- No inputs/projections
2- Inputs from other cortical areas
3- Projects to other cortical areas
4- Input from thalamus
5- Project to brainstem and spinal cord
6- Projects to thalamus
```
298
What are the components of the parasympathetic nervous system?
- Cranial outflow- CN 3,7,9,10
| - Sacral outflow
299
What are the components of the the sympathetic nervous system?
Sympathetic chain T1-L2
| Adrenal gland
300
What receptors and neurotransmitters are present in the sympathetic ns?
ACh with a nicotinic receptor, then noradrenaline
| - Receptors are alpha 1 (in smooth muscle) and alpha 2 (in blood vessels)
301
What receptors and neurotransmitters are present in the parasympathetic ns?
ACh with a nicotinic receptor, then ACh with a muscarinic receptor
- Receptors are beta 1 (in heart), beta 2 (in bronchi) or beta 3
302
Give an example of an acute and a chronic primary ANS disorder
Acute- Pan-dysautonomia
| Chronic- Parkinson's disease
303
How can the autonomic NS CVS problems be tested?
Testing BP
Testing BPM
Head up tilt test
304
What are the components of the striatum?
Putamen
| Caudate nucleus
305
What are the components of the globus pallidus?
Internal segment
| External segment
306
Where is dopamine produced and where does it act?
It is produced in the substantia nigra (melanin is produced as a byproduct). It acts on the axons in the striatum.
307
What is the pathalogical cause of parkinsons disease?
There is disease of the dopamine neurons in the substantia nigra so dopamine is not produced effectively.
The subthalamic nucleus is inhibited.
308
What is the pathalogical cause of Huntington's disease?
The head of the caudate and the cortex shrinks making ventricles appear bigger (can be seen on a CT). This means that there is too much dopamine.
It is autosomal dominant and fully penetrant
309
What are the symptoms of Parkinsons?
```
Increased muscle tone
Reduced movement
Not enough dopamine
Problems with doing up buttons/ keyboards
Smaller writing
Deteriorated walking; small steps, dragging one foot, feet close together, etc.
Tremor at rest (may be on one side only)
Pain
```
310
What are the treatments for Parkinsons?
L-DOPA (to correct dopamine deficit)- but becomes less effective and more side effects develop the longer that it is used
Deep brain stimulation- functional lesioning of the subthalamic nucleus
311
What are the symptoms of Huntington's disease?
```
Chorea
Dementia/psychiatric illness
Personality change
Decreased muscle tone
Overshooting movements
Too much dopamine
```
312
What is the treatment for choriform movements?
Dopamine receptor blockers
313
What is the WHO definition of mental health?
Mental health is a state of well being in which every individual realizes his or her own potential, can cope with normal stresses of life, can work productively and fruitfully, and is able to make a contribution to his or her community
314
List some CMHDs
```
Depression
Generalized anxiety disorder
Social Anxiety disorder
Panic Disorder
OCD
PTSD
Phobias
```
315
What are the symptoms of depression?
```
Loss of interest
Decreased energy
Feelings of guilt or low self worth
Disturbed sleep or appetite
Poor concentration
These must last most of each day, every day for more than 2 weeks
```
316
How much more likely are women than men to have a CMHD?
2x more likely
317
What are some social determinants of CMHDs?
```
Low education
Material Disadvantage
Unemployment
Debt
Loneliness
```
318
What are the different levels of interventions for CMHDs?
Individual level
Service level
Community level
319
What is included in individual level intervention?
Medication, psychological therapy, CBT
Culturally sensitive
Collaborative
320
What is included in service level intervention?
Management within primary care, focusing on prevention and early identification
Holistic approach
Outcomes focused
Joining the gaps
321
What is included in community level intervention?
Strengthening protective factors e.g. programmes in schools
| Reducign risk factors
322
What is IAPT and what is its goal?
Improving access to psychological therapy
Low or high intensity
Lower socio-economic groups are more likely to access treatment
Shorter waiting times
323
Describe the "take it easy" trap of chronic pain
Avoidance of activities due to concerns about doing harm, and avoiding activities associated with pain. The patient therefore does less and less over time, and has less contact with others. This can lead to a loss of fitness and depression.
324
What are the three P's of pain management?
Pacing
Planning
Prioritising
325
What cells line the ventricles?
Ciliated ependymal cells
326
How does CSF drain?
Arachnoid granulations
| Peripheral nerves to lymphatics
327
How does interstitial fluid drain into the CSF?
Perivascular channels
328
What nucleus does the superior colliculus communicate with?
Lateral geniculate nucleus of thalamus
329
What nucleus does the inferior colliculus communicate with?
Medial geniculate nucleus of thalamus
330
What does a small response from a NCS suggest?
Axonal degeneration
331
What does a slow response from a NCS suggest?
Demylenation
332
Briefly explain an EMG
Use a needle to pick up electrical activity from a muscle when the patient contracts it. Record the activity of individual motor units. Large motor unit- compensatory innervation, small motor unit- breakdown of muscle
333
Briefly explain an EEG
Electrodes are placed in specific locations on the head. Ask the patient to do various things such as close eyes.
334
What are the characteristics of a frontal lobe seizure?
Brief
Often arise in sleep
Fencing posture
