Week 4 Flashcards
(167 cards)
1
Q
What are the 2 ways a person can be unconscious?
A
Sleep
Coma
2
Q
What are the 3 levels of Consciousness?
A
Wakefulness (alert, detects objects)
Core Consciousness (wakefulness + emotional response and memory)
Extended Consciousness (all above + self awareness, language and creativity)
3
Q
How does an EEG (electroencephalogram) work?
A
Picks up activity of synchronised dendritic activity (the more neurons synchronised, the bigger the peaks on EEH)
Doesn’t pick up individual neurons
4
Q
How do neurons become synchronised?
A
Either by neuronal interconnections or by pacemaker
5
Q
How many pairs of electrodes are used in an EEG?
A
19 pairs
6
Q
List the stages of sleep?
A
Awake
Stage 1-4
REM
7
Q
Describe the Awake stage of sleep
A
Eyes closed - alpha high frequency + low amp
Eyes open - beta waves + waves of activity
8
Q
Describe Stage 1 of sleep
A
Easily roused, slow rolling eye movements
Some theta waves w/ slower freq + higher amp waves
9
Q
Describe Stage 2 of sleep
A
Begin K complexes & sleep spindles
No eye movement but body movement still possible
10
Q
Describe Stage 3 of sleep
A
Slower freq w/ delta waves
Harder to rouse
Few spindles
11
Q
Describe Stage 4 of sleep
A
Deepest sleep, hardest to rouse
High amplitude (delta waves)
Heart rate & BP lower
12
Q
Describe REM sleep
A
Fast beta waves and REM
Easier to rouse than stage 4
Dreaming, recalled + low muscle tone
13
Q
What structure in the brain helps turn on and off sleep?
A
Reticular formation through interactions w/ thalamus
14
Q
Excitation of the reticular formation will lead to what result in the context of sleep?
A
Depolarisation of thalamus (excitation) which will lead to non-rhythmic output from thalamus, therefore Increased arousal
15
Q
Inhibition of the reticular formation will lead to what result in the context of sleep?
A
Hyperpolarisation of the thalamus (less excited) which will lead to rhythmic output of the thalamus, therefore slow EEG waves in cerebral cortex
16
Q
What is the broad definition of Epilepsy?
A
A continuing tendency to have recurrent, unprovoked seizures
17
Q
What are individuals w/ epilepsy at risk of?
A
SUDEP
Sudden Unexpected Death
1 in 1,000 epileptics
18
Q
How do you realistically determine what type of epileptic seizures an individual suffers from?
A
History taking and witness testimony of the seizure
+/- Aura, Deja vu, Fear, Warning
Abnormal Movements
Memory loss after, confusion
19
Q
What are the 3 main categories of epileptic seizures?
A
Focal (Aware / Unaware)
Generalised seizures
Unclassified seizures
20
Q
What are all the subtypes of Generalised seizures?
A
Absence (typical / atypical)
Myoclonic
Clonic
Clonic-tonic
Tonic
Atonic
21
Q
What are some potential symptoms of Focal aware seizures?
A
Consciousness is preserved
Aura
Elaborate motor output
Rhythmic movement
May see faces
Contralateral visual hallucination
Underwater hearing
Hear music
22
Q
What are some symptoms of Focal unaware seizures?
A
May be impaired consciousness
Temporal lobe seizures not common (40% of all cases)
Often benign with aura, linked to location
Automatisms & unusual sounds
Occasionally autonomic responses
Post ictal headache w/ confusion
May evolve into Generalised seizures
23
Q
Describe Typical Absence seizures
A
Sudden onset (no aura)
Abrupt cessation
Brief duration (20s)
May be w/ clonic jerking of eyelids
24
Q
Describe Atypical Absence seizures
A
Postural tone changes
Autonomic phenomena
Automatisms
25
What can't be used to treat Myoclonic seizures?
Carbamazepine
26
Describe Atonic seizures
Sudden loss of postural tone; often in children but can be present w/ adults
27
Describe Tonic-clonic seizures
Major convulsions w/ rigidity (tonic) and jerking (clonic)
slows over 60-120 sec
28
Describe Status Epilepticus
More than 5 mins of continuous conclusive seizure activity
or
2 or more sequential seizures spanning this period without full recovery between seizure
29
What are some diagnostic tests for Epilepsy?
ECG (cardiac problems can correlate with epilepsy)
EEG
CT scan (only if suspicious of brain tumour)
MRI (areas of scarring, reduced perfusion)
30
What may pre-dispose one to an epileptic seizure?
Scar tissue
Developmental issues
Pyramidal cell damage
Tumours
31
What are examples of potential triggers of epileptic seizures?
Tiredness
Alcohol
Certain drugs
Change of medication
32
Treatment for epilepsy
Anti-Epileptics (AED)
Treats the symptoms of epilepsy but not the cause
33
Targets for AEDs
Supress excit neurotransmitter system (inhib Na channels)
Enhance the inhib neurotransmitter system (GABA (Benzodiazepines))
Block voltage-gated inwards +ve currents (NA+ or Ca++)
Increase outward +ve current (K+)
Many AEDs pleiotropic
34
What is always present in Generalised seizures?
Alteration to consciousness
35
What are some drugs used in the treatment of Focal onset seizures?
Carbamazepine
Lamotrigine
36
What are some drugs used in the treatment of Generalised onset seizure?
Valproic acid
Lamotrigine
37
What drug is used to treat Absence seizures?
Ethosuximide
38
What mechanisms happens to cause Hebbian learning?
Cells fire simultaneously to increase the synaptic associations
39
Define Habituation
The process by which repeated stimulus leads to a decreased response (& decreased NT release)
40
Define Sensitisation
The process by which repeated stimulus leads to an increased response
This is mediated by an interneuron
41
Describe long term potentiation (LTP)
Needed for long term memory, +ve reinforcement of a signal will lead to a strengthened signal
PATH SPECIFIC
42
Describe long term depression (LTD)
Used to modulate LTP or even reverse it
When synapses become less efficient at transmitting signals
43
Describe short term memory
Brief memory (seconds)
Easily displaced by another stimulus
Can be extended into working memory by:
a) repetition in phonic loop or
b) chunking which links familiar chunks together to extend the size of chunk
44
What is the most commonly used clinical test for short term memory chunks?
Digit span - told no. of digits and asked to immediately repeat same numbers (norm is about 6-7 digits)
45
Define working memory
Maintenance and integration of info in an active state for a relatively brief time in order to achieve a short term task/goal
Mixture of short and/or long term memory
46
Long term memory can be divided into what 2 groups?
Declarative memory
&
Non-declarative memory
47
What are the 4 steps in the process of learning?
Encoding (mem created)
Storage (persistence of mem traces)
Retrieval (mem recovery)
Consolidation (strengthening of mem traces)
48
What are some structural changes that happen during consolidation in learning?
Formation of more receptors or even more dendritic spines
49
What structures are involved in non-declarative memory?
Amygdala
Caudate nuc.
Putamen
Cerebellum
50
What's the difference between retrograde and anterograde amnesia?
Retro is losing memories from their past, Antero is when they can't properly form new memories
51
What was one valuable piece of info did we gather from the case of HM?
Declarative, non-declarative, short term and long term memory are not processed in the same place or by the same mechanisms
52
What is the role of association areas along with sub-cortical components within cognition?
Determine the perceptual qualities of the modality
53
What is multi-sensory integration?
Combination of processed sensory perceptions are used to determine what is happening and where it's happening
54
Describe the process by which multi-sensory integration occurs
Sub-cortical structures & association fibres move info through the association cortices for processing + integration to become either a reflex or a cognitive state
55
What does the McGurk effect show?
Visual info is more valuable than auditory info
56
Define Synaesthesia
The conflation of sensory experiences from one sensory domain with those from another, or the mixing of two modalities of the same sensory domain
eg. colour-graphemic synaesthesia
57
What is conduction aphasia?
Link between Wernicke's and Broca's area is damaged
typically means reduced ability to repeat spoken words
58
Define Wernicke's aphasia
Nonsensical speech due to reduced comprehension of speech
Can't understand their own or others speech (also affects reading words)
59
Define Broca's aphasia
Aka motor or non-fluent aphasia
Patients have difficulty speaking - often stuttering to find right word. Aware they are making little sense. No problem responding to the spoken or written word, can comprehend
60
Define Aprosodia
Robotic or monotonic speech patterns due to damage in non dominant lobe affecting variation in tone of voice
61
What is a unique trait about split brain patients and describing objects felt in either hand?
Assuming L dom hemisphere, they wont be able to describe objects felt in left hand nor objects seen on left side
62
What are potential causes of a lesion from fastest onset of symptoms to slowest?
Vascular risk factors
Infectious
Autoimmune
Tumour / Metastasis
Degenerative neuron disease
63
If a patient presents with problems with eye movement, where is there likely to be a problem in the brainstem?
Midbrain
64
If a patient presents with problems with mastication, where is there likely to be a problem in the brainstem?
Pons
65
If a patient presents with problems with phonation, speech and/or swallowing, where is there likely to be a problem in the brainstem?
Medulla
66
What are the 4 general functions of the limbic system?
Emotion + drives (amygdala)
Homeostasis + motivation (hypothalamus)
Olfaction (olfactory cortex)
Memory (hippocampus)
67
Where is the Amygdala located?
Anterior to the tip of the hippocampus in the temporal lobe
68
Where are the Amygdala's most significant afferent fibres from?
Frontal, Temporal and Parietal lobes receiving cognitive info
69
Where are the amygdala's most significant efferent fibres going to?
Hypothalamus and limbic cortex providing emotional cognisance, and visceral/homeostatic info
70
What is Kluver-Bucy syndrome?
Bilateral temporal lobe lesions often affecting hippocampus and/or amygdala
71
What are symptoms of Kluver-Bucy syndrome?
Visual recognition impairment for fear in others
Heightened sexual appetite
Flattened emotions
Oral tendencies (hyperorality)
72
What are common symptoms of lesions in the amygdala?
A loss of recognition of fear and anger in other's faces
73
What is the main effector of the limbic system?
Hypothalamus
74
What are the main groups of functions of the Hypothalamus?
Vegetative functions (Homeostasis)
Endocrine functions (Hypophyseal)
Behavioural functions
75
What is the role of the anterior Insular cortex
Provides introspection that allows the interpretation of sensation as joy or disgust
76
What sections of the limbic system has reduced activity in depression?
Ventromedial portion of prefrontal cortex (goal setting / planning)
Cingulate Gyrus (emotion / cognition)
77
The Medial Longitudinal Fasciculus connects links what 3 CN's in eye movement?
Oculomotor III
Trochlear IV
Abducens VI
78
Hypothalamus receives afferents from what structures?
Neocortex
Eyes
Amygdala
Spinal cord
Pain & sens integration in brainstem nuclei
79
Hypothalamus sends efferents to what structures?
Neocortex
Spinal cord
Amygdala
Medulla
Ant. & Post. Hypophyseal
Pain & sens integration in brainstem nuclei
80
Describe the Limbic reward loop
Originates in the Ventral Tegmentum (dopamine) and projects to the medial prefrontal cortex (mPFC), amygdala & hippocampus as well as nuc. accumbens and ventral pallidum
Big role in Motivations and Addictions
81
How does limbic system help with pain management?
Limbic system interconnects with PAG (periaqueductal grey matter). PAG can reduce activity in ascending pain pathway w/ its effects agonised by endorphins (and opiates)
82
What is the relationship between Bipolar disorder and the Ventromedial portion of the Prefrontal cortex?
In depressive phase this is virtually inactive
In manic phase this is hyperactive
83
What is the relationship between Bipolar disorder and the Cingulate gyrus?
ant. portion is more active during depressive phase and less active during manic
Opposite for the post. portion
84
What is the mortality from meningococcal Meningitis as well as meningococcal Sepsis?
15% & 40% respectively
85
What are some possible complications of meningitis?
Seizures
Hearing issues
Other CN problems
Focal paralysis
ect.
86
What are some possible complications of sepsis?
Limb amputations
Arthritis + joint pain
Skin necrosis + scarring
Organ dysfunction
87
What is the difference between Meningitis and Encephalitis?
Meningitis is inflammation of the meninges, Encephalitis is inflammation of the brain parenchyma
88
Define sepsis
Life-threatening organ dysfunction caused by body's extreme, dysregulated response to infection
89
If infectious agents breach the BBB, what condition will this person get?
Encephalitis
90
If infectious agents breach the Blood-CSF barrier, what condition will this person get?
Meningitis
91
What are the 3 main causes of meningitis?
---Infection---
Auto-immune disease
Malignancy
92
How could you roughly identify what bacteria may be causing meningitis when a patient comes to you?
By their age
Different bacteria will cause meningitis based on age
93
Describe Neisseria Meningitidis
G -ve Bacteria
Normal microbiota in nasopharynx
transmission via droplet spread
94
Describe Haemophilus Influenzae
G -ve Bacteria
6 capsular serotypes (a-f)
95
Describe Streptococcus Pneumoniae
G +ve Bacteria
Normal microbiota in nasopharynx
Common cause of meningitis in young children and adults with specific risk factors
96
What are the 3 main bacteria that cause meningitis?
Neisseria Meningitidis
Haemophilus Influenzae
Streptococcus Pneumoniae
97
What are some clinical features of Meningitis in babies/young children?
Fever
Headache
Non-blanching rash
Photophobia
Seizures
98
What are some diagnostic blood tests you can do to look for meningitis?
Biochemistry - U&E, lactate, glucose
Haematology - FBC, clotting
Microbiology - blood culture, PCR
99
What are some diagnostic CSF tests you can do to look for meningitis?
Biochemistry - protein & glucose
Microbiology - WBC count, PCR, Bacteria culture
100
How do you typically treat bacterial meningitis?
Antibiotics
+/-
Steroids
101
How do we prevent bacterial meningitis?
Routine vaccinations
102
What is different between bacterial and viral meningitis?
Viral is less severe and more common than bacterial
103
How do we identify viral meningitis?
PCR or CSF
104
What treatment is there for viral meningitis?
None as it's regarded as 'benign' & self limiting
105
What is the most common cause of Encephalitis?
Herpes Simplex Virus - 1
(HSV-1)
106
What are the main symptoms & signs of encephalitis?
Altered Cerebration:
confusion, abnormal behaviour, seizures, fever
107
How do we treat Encephalitis?
High dose IV Aciclovir
108
What often cause brain abscess'?
Oral nasopharyngeal microbiota
109
What is the pathophysiology of brain abscess'?
Diffuse inflammation -> focal lesion and pia matter suppuration
110
What are the symptoms & signs of a brain abscess?
Headache, focal neurology, seizures
111
How do we test for brain abscess'?
CT / MRI scan
+/- invasive sampling
112
How do we treat brain abscess'?
Antibiotics
113
What are the 2 segments of the eye called?
Ant. and Post. Segment
114
What is the largest layer of the Cornea?
Stroma
115
What is the role of the Endothelial cells in the Cornea?
Remove water/moisture from the stroma to keep it dry (allows clear vision)
116
What is the Near Triad?
Miosis
Convergence
Accommodation
Related to looking at a very close object
117
What is the name of a refractive error in the eye?
Presbyopia (need glasses)
118
What is it called to be near sighted?
Myopia
119
What is it called to be long sighted?
Hypermetropia
120
What is an individual with Myopia more at risk of also getting?
Open angle glaucoma
Retinal detachment
121
What is an individual with Hypermetropia more at risk of also getting?
Angle closure glaucoma
Ischaemic optic neuropathy
122
What is the main cause of visual impairment in the world?
Uncorrected refractive error (URE)
123
What is the main cause of blindness in the world?
Cataracts
124
What is the difference between a Snellen chart and an Arclight chart?
Arclight is 50% smaller w/ 50% smaller letters (also use at 50% distance ie. 3m instead of 6m)
125
When is a person deemed blind by WHO?
When they can't read any letters from 3m (worse than 3/60 vision)
126
What is Trachoma?
Scarring of cornea due to Chlamydia
127
Name all structures in the Ant. Segment of eye
^^^
128
What are the differences between Rods and Cones in the Eye?
^^^
129
What cells deal with peripheral vision?
Rods
130
What cells deal with focused vision?
Cones
131
What vitamin is important for retinal health and what will be a result of deficiency in this vitamin?
Vit A
Night blindness -> Total blindness -> Death
132
What retinal issue is more apparent in richer countries?
Age related Macular Degeneration (AMD)
133
What structures act as innate defence for the eye?
Orbit & eyelids
Tears + mucin
Ocular Epithelium
134
What structures act as adaptive defence for the eye?
Eye-associated lymphoid tissue
Langerhan's cells
Lymphocytes
135
What is the function of Lysozyme and where is it found?
Enzyme that cleaves bacterial peptidoglycans and also helps to protect against viruses and fungi
Found in tears, saliva, and mucous
136
What is the function of Lactoferrin and where is it found?
Binds iron - starves bacteria and fungi, disrupts cell walls, anti-viral
Found in tears, saliva, mucous, and milk
137
Lysozyme and Lactoferrin work together to help protect against what type of Bacteria?
Gramm -ve
138
What are some common eye infections?
Conjunctivitis
Keratitis (viral, bacterial)
Onchocerciasis (parasitic infection)
Orbital Cellulitis (pre/post septal)
139
What are 2 common causes of conjunctivitis in baby?
Gonorrhoea and Chlamydia
140
What is one risk factor for Bacterial Keratitis?
Contact lenses that are left in for too long
141
What are some causes of Corneal ulcers?
Tear film deficiencies
Eyelid malformation / dysfunction
Endogenous cause
Exogenous cause
142
What are some symptoms of HSV Keratitis?
Always unilateral
Painful, red, watery, photophobic
Dendritic ulcer, new vessels, scarring
143
What is used to treat HSV Keratitis?
Topical and oral Aciclovir
144
What may cause Trachoma?
Chlamydia trachomatis infection
Chronic Keratoconjunctivitis
145
What is used to treat Onchocerciasis?
Ivermectin
146
What are some signs of Orbital Cellulitis?
Swelling
Redness
Limited eye movement
Proptosis
Diplopia w/ pain
147
What pathogens may cause Orbital Cellulitis?
Haemophilus Influenzae
Staphylococcus Aureus
148
What is Retinochoroiditis often related with?
HIV / AIDS / Toxoplasma
149
What is used to treat Toxoplasmosis due to Retinochroiditis?
Corticosteroids
150
What is used to treat Cytomegalovirus retinitis during late HIV disease?
Antiviral Ganciclovir
151
What may cause Endophthalmitis in the eye AND how is it treated?
Post intra-ocular operation
Trauma w/ inoculation of foreign body
Intra-ocular & systemic antibiotics
152
What are some common infections of the ear and nose?
Otitis Externa (bac + fungal / acute or chronic)
Otitis Media (viral + bac / acute, chronic, suppurative)
Mastoiditis (bac)
Sinusitis (acute or chronic)
153
Who is most effected by Otitis Media AND what are some signs?
Small children, 50% viral in origin
Red ears, fever, poor feeding, restlessness, hearing difficulties
154
What is Mastoiditis a severe complication of AND what are some symptoms and treatments?
Otitis Media
Redness, tenderness and pain behind ear
Treat w/ IV antibiotics
155
What does sinusitis often follow?
Common cold
156
What are some common issues of the throat?
Common cold
Acute Pharyngitis - sore throat
Cytomegalovirus
Tonsilitis
157
What are some common symptoms of Viral Conjunctivitis?
Sticky eyes
Watery
Pink
Itchy
158
What pathogens cause Viral Conjunctivitis?
Coronaviruses
&
Rhinoviruses
159
What are some common symptoms of Adenovirus Conjunctivitis?
Bilateral, v sticky, red and painful eye
Enlarged ipsilateral Periauricular lymph node
160
What are some common symptoms of Bacterial Conjunctivitis?
Similar to viral (sticky, red and painful)
Discharge more yellow and thick
161
What are some potential causes of Bacterial Conjuntivitis?
Haemophilus Influenzae
Streptococcus Pneumoniae
162
Name some drugs that could be used to treat Bacterial Conjunctivitis?
Chloramphenicol
Fusidic Acid
163
What are some symptoms of Cytomegalovirus infections?
Cold-like symptoms
Sore throat
Fever
Fatigue
Swollen glands
164
What would be used to treat Cytomegalovirus infections?
Ganciclovir
165
What is a Quinsy Peritonsillar Abscess?
Collection of pus between tonsillar capsule and sup. constrictor muscles
166
How do we treat Quinsy Peritonsillar Abscess'?
Needle aspiration / drainage
IV antibiotics
IV steroids
167
What is the name of the position children w/ acute Epiglottitis may take?
Tripod position
