Neurology Flashcards
1
Q
What is the central nervous system (CNS) composed of?
A
The brain and spinal cord.
2
Q
What components make up the peripheral nervous system (PNS)?
A
The somatic nervous system (SNS), autonomic nervous system (ANS), and enteric nervous system (ENS).
3
Q
What are the three basic functions of the nervous system?
A
- Sensory function (detecting stimuli),
- Integrative function (analyzing and storing sensory information)
- Motor function (responding to integrative decisions).
4
Q
What is the function of neuroglia in the CNS?
A
They support, nurture, protect neurons, and maintain the interstitial fluid around them.
5
Q
What are the two types of neuroglia that produce myelin sheaths?
A
Oligodendrocytes (CNS) and Schwann cells (PNS).
6
Q
How much does the human brain weigh?
A
Approximately 1.4 kg.
7
Q
What are the three layers of the spinal meninges?
A
Dura mater, arachnoid mater, and pia mater.
8
Q
What is cerebrospinal fluid (CSF) and what are its functions?
A
CSF is a clear liquid that provides mechanical protection, chemical protection, and circulation for nutrients and waste removal in the CNS.
9
Q
Where is CSF produced and how does it circulate?
A
CSF is produced in the choroid plexuses in the ventricles and circulates through the subarachnoid space around the brain and spinal cord.
10
Q
What is the Monro-Kellie hypothesis?
A
The hypothesis stating that any increase in the volume of one of the cranial components (brain, blood, CSF) must be compensated by a decrease in one or both of the others to maintain normal intracranial pressure (ICP).
11
Q
What is hydrocephalus?
A
A condition caused by the failure of CSF to form or drain normally, leading to increased intracranial pressure (ICP).
12
Q
What is the role of a ventriculoperitoneal (VP) shunt?
A
It is a medical device used to divert cerebrospinal fluid from the brain’s ventricles to the peritoneal cavity, commonly used in treating hydrocephalus.
13
Q
What are the primary arteries supplying blood to the brain?
A
The internal carotid and vertebral arteries.
14
Q
What is the blood-brain barrier (BBB) and its function?
A
The BBB consists of tight junctions between capillary endothelial cells in the brain, which regulate the passage of substances from the blood into the brain, allowing essential substances to pass while excluding harmful ones.
15
Q
What substances can cross the blood-brain barrier easily?
A
Lipid-soluble substances such as O2, CO2, steroid hormones, alcohol, nicotine, caffeine, and water.
16
Q
How can increased intracranial pressure (ICP) be treated?
A
Treatment can involve diuretics (e.g., Acetazolamide, Furosemide), osmotic diuretics (e.g., Mannitol), steroids (e.g., Dexamethasone), and anti-inflammatory medications.
17
Q
What is the pathophysiology of cerebral ischemia?
A
Cerebral ischemia occurs when blood supply to the brain is interrupted, leading to neuronal injury due to lack of oxygen and glucose, which may cause inflammation, increased capillary permeability, and cell death.
18
Q
What are common predisposing factors for Multiple Infarct Dementia (MID)?
A
Hypertension, smoking, hypercholesterolemia, diabetes mellitus, carotid artery stenosis, and cardiac problems such as atrial fibrillation.
19
Q
What is the role of the brain in terms of oxygen and glucose consumption?
A
The brain, which makes up 2% of body weight, consumes about 20% of the body’s oxygen and glucose, even at rest.
20
Q
What happens when blood flow to the brain is interrupted for 1–2 minutes?
A
It impairs neural function. Total deprivation of blood flow for about 4 minutes can cause permanent brain injury.
21
Q
What is the treatment for increased intracranial pressure due to bleeding or ischemia?
A
The treatment can include managing the underlying cause, using medications (e.g., anti-inflammatory drugs, osmotic diuretics), and possibly surgery in severe cases.
22
Q
What is the function of the cerebral cortex?
A
The cerebral cortex is responsible for higher mental functions such as sensory perception, motor control, and complex cognitive processes like memory and decision-making.
23
Q
How many neurons are in the human brain?
A
The human brain contains approximately 100 billion neurons, with about 100 trillion connections between them.
24
Q
What are association areas in the brain?
A
Association areas process and integrate sensory information, enabling higher cognitive functions such as memory, learning, and problem-solving.
25
What is the difference between the right and left hemispheres of the brain?
The right hemisphere is generally responsible for creative and spatial tasks, while the left hemisphere handles language and analytical functions.
26
What are the physical changes in the brain associated with aging?
Aging can lead to brain atrophy, especially in areas responsible for memory and cognitive function, and a decrease in overall brain volume.
27
What is the prevalence of Alzheimer’s disease in different age groups?
40-65 years: 1 in 1000
65-70 years: 1 in 50
70-80 years: 1 in 20
80+ years: 1 in 5
28
What are the key neurological changes in Alzheimer's disease?
Alzheimer's disease affects language, memory, intelligence, and personality, leading to emotional and behavioral changes.
29
How does Alzheimer's disease affect the brain?
Alzheimer's disease causes damage to the hippocampus and other brain regions, with the development of plaques and neurofibrillary tangles that impair neuronal function.
30
What are plaques and neurofibrillary tangles in Alzheimer's disease?
Plaques are abnormal clusters of amyloid-beta proteins, and neurofibrillary tangles are twisted tau proteins inside neurons, both disrupting brain function.
31
Which neurotransmitter is commonly targeted in Alzheimer’s treatment?
Acetylcholine is targeted by medications such as Aricept, Galantamine, and Rivastigmine to improve cognitive function by preventing acetylcholine breakdown.
32
What is multi-infarct dementia?
Multi-infarct dementia is caused by multiple small strokes (cerebral infarcts), gradually impairing mental function as brain tissue is damaged.
33
What are the risk factors for multi-infarct dementia?
Risk factors include hypertension, smoking, hypercholesterolemia, diabetes, carotid artery stenosis, and atrial fibrillation.
34
How much brain tissue loss can cause dementia in multi-infarct dementia?
A loss of as little as 10 ml of strategically placed brain tissue may be enough to cause dementia.
35
What is the progression of dementia in Alzheimer's disease and multi-infarct dementia?
Dementia progresses as brain regions are increasingly damaged, leading to more severe cognitive and functional decline.
36
What is hydrocephalus and how does it relate to intracranial pressure?
Hydrocephalus is a condition where abnormal cerebrospinal fluid (CSF) accumulation increases intracranial pressure, potentially causing brain damage.
37
What is a ventriculoperitoneal (VP) shunt used for?
A VP shunt is a medical device used to redirect cerebrospinal fluid from the brain’s ventricles to the peritoneal cavity to manage conditions like hydrocephalus.
38
How does cerebral ischemia affect the brain?
Cerebral ischemia occurs when blood supply to the brain is disrupted, leading to a lack of oxygen and glucose, which causes neuronal injury, inflammation, and cell death.
39
What are the main consequences of cerebral ischemia?
Increased capillary permeability, inflammation, neurotransmitter release, and cytotoxic cell death are key consequences of cerebral ischemia.
40
What is the main cause of Parkinson's disease (PD)?
Parkinson's disease is primarily caused by the degeneration of the basal ganglia and the dopamine-secreting pathway, leading to motor control issues.
41
How does the loss of dopamine affect the motor cortex?
The loss of dopamine inhibits the motor cortex's ability to function properly, leading to slower movements (bradykinesia) and rigidity.
42
What happens when the indirect pathway becomes overactive in Parkinson’s disease?
The overactive indirect pathway, which normally prevents movement, causes the slowed movements and rigidity seen in Parkinson’s disease.
43
What emotional symptoms are associated with Parkinson’s disease?
- Depression: Feelings of sadness and loss of interest.
- Anxiety: Excessive worry or fear.
- Apathy: Lack of motivation or interest in activities.
- Irritability: Increased frustration or mood swings
- Cognitive changes: Difficulty with memory and concentration.
- Hallucinations and delusions: In advanced stages, causing distress and confusion.
44
What causes the cell dysfunction and death in Parkinson’s disease?
Cell dysfunction and death in Parkinson’s disease are caused by oxidative stress, mitochondrial dysfunction, loss of nerve growth factors, and apoptosis.
45
What percentage of the population has a genetic predisposition to Parkinson’s disease?
About 15% of the population has a genetic predisposition to Parkinson’s disease.
46
Which part of the brain is primarily affected in Parkinson's disease?
The substantia nigra, a region in the mid-brain, is primarily affected in Parkinson’s disease.
47
What is the role of Lewy bodies in Parkinson's disease?
Lewy bodies, formed by misfolded proteins such as alpha-synuclein, accumulate in residual neurons and contribute to the progression of the disease.
48
What cognitive issue arises as Parkinson’s disease progresses?
As Parkinson’s disease progresses, Lewy body dementia can develop, leading to slow, gradual cognitive impairment.
49
What are the motor symptoms seen in Parkinson’s disease?
The motor symptoms include resting tremor, bradykinesia (slowness of movement), rigidity, and unintentional muscle movements or twitching.
50
How does the loss of dopamine affect muscle tone?
The loss of dopamine removes the normal inhibition of muscle tone, leading to increased muscle tone and rigidity.
51
What is the effect of unopposed cholinergic activity in Parkinson's disease?
Unopposed cholinergic activity promotes muscle tone, contributing to the rigidity and involuntary muscle movements seen in Parkinson’s disease.
52
What non-motor symptoms are associated with Parkinson’s disease?
Non-motor symptoms include visual hallucinations, memory disorders, and REM sleep problems.
53
The lateral ventricles are filled with?
Cerebrospinal fluid
54
The meninges would be found within which body cavity?
cranial
55
As intracranial pressure (ICP) rises, brain tissue will become ischaemic and damaged. The pathological mechanisms that might contribute to this damage could include:
A = Inflammation
B= Free Radical production
C= Unregulated cell death
D = All of the above
D = Inflammation, Free Radical production and Unregulated cell death are all pathological mechanisms that might contribute to the damage in brain tissue from risen intracranial pressure
56
In a healthy person, what increases cerebral blood flow?
An increase in carbon dioxide levels in the blood
57
What is the name for the middle layer of the meninges that surrounds the brain?
Arachnoid mater
58
6.
Julie, aged 19 years came off her motor bike 2 days ago and suffered what she thought was a minor a head injury. After a initial recovery, however, she is now suffering from acute head ache and altered consciousness. Healthcare workers are concerned that she might have raised intracranial pressure due to a cerebral bleed. It is decided that intracranial pressure monitoring should be commenced.
What would be a normal value for intracranial pressure that you might expect Julie to have?
0-15 mmHg
59
Sam was hit by a slow moving car and catapulted over the bonnet. He sustained abdominal, shoulder and head injuries. When you check his pupils, you find the left larger than the right and not reacting to light:
L= size 6- R=size 3+
Which nerve is being affected in this situation?
Oculomotor nerve (III)
60
Omar is in a road traffic accident hitting his head on the windscreen and being thrown backwards. He arrives in the emergency department and is diagnosed with raised intracranial pressure from a space-occupying lesion.
What is the most likely cause of the space-occupying lesion that occurs within Omar's skull?
haematoma
61
If Omar's intracranial pressure continues to rise, the brain can potentially herniate through an opening in the skull. What structure would the medulla oblongata potentially move through to cause brain stem death?
foramen magnum
62
What mnemonic helps remember the cranial nerves?
"Oh Oh Oh To Touch And Feel Very Good Velvet"
Oh: Olfactory
Oh: Optic
Oh: Oculomotor
To: Trochlear
Touch: Trigeminal
And: Abducens
Feel: Facial
Very: Vestibulocochlear
Good: Glossopharyngeal
Velvet: Vagus
, Such: Spinal accessory
Heaven: Hypoglossal
63
What mnemonic helps remember the nerve class of cranial nerves?
"Some Say Marry Money But My Brother Says Big Boobs Matter Most"
Some: Sensory
Say: Sensory
Marry: Motor
Money: Motor
But: Both
My: Motor
Brother: Both
Says: Sensory
Big: Both
Boobs: Both
Matter: Motor
Most: Motor
64
What is the function of the Olfactory Nerve (I)?
Senses smell.
65
What is the function of the Optic Nerve (II)?
Detects vision.
66
What is the function of the Oculomotor Nerve (III)?
- Controls eye movements (including pupil constriction).
- Controls focusing of the lens.
67
What is the function of the Trochlear Nerve (IV)?
Controls eye movement (downward gaze, intorson).
68
What is the function of the Trigeminal Nerve (V)?
- Detects head and face sensations
- Muscles of mastication (chewing)
69
What is the function of the Abducens Nerve (VI)?
Eye movements (abduction or lacteral movements)
70
What is the function of the Facial Nerve (VII)?
Controls:
- Muscles for facial expressions.
- Detects taste.
- Lacrimal and Salivary glands.
71
What is the function of the Vestibulocochlear Nerve (VIII)?
Senses balance.
Senses sound (hearing).
72
What is the function of the Glossopharyngeal Nerve (IX)?
Sensations from pharynx and posterior tongue.
Detects tongue sensations.
73
What is the function of the Vagus Nerve (X)?
Controls the muscles for swallowing.
Detects tongue and abdominal sensations.
Sensations from pharynx and larynx
74
What is the function of the Hypoglossal Nerve (XII)?
Movements of tongue
75
What is the function of the Spinal Accessory Nerve (XI)?
Controls trapezius and sternocleidomastoid muscles (shoulder and neck movement).
76
Cerebrospinal fluid (CSF) flows around the brain and spinal cord. Where is it produced?
choroid plexus in each ventricle
77
When a brain cell dies, what physiological mechanisms are triggered?
- Release of neurotransmitters
- Release of free radicals and oxidants
- Inflammation and an increase in capillary permeability
78
Which of these equations shows the correct calculation for cerebral perfusion pressure?
Cerebral perfusion pressure (CPP) = mean arteral pressure (MAP) - intracranial pressure (ICP)
79
What is the sequence of events that occurs causing brain damage?
Bleed occurs > ICP rises > cerebral blood flow is impaired > ischaemia occurs > brain potentially damaged
80
Sam has a CT scan and requires surgery to evacuate a subdural haematoma. Taken to critical care afterwards, he is at risk of developing raised intracranial pressure.
How will you recognise an increased intracranial pressure?
Increased blood pressure and decreased heart rate
81
Why do you see the vital signs in increased intracranial pressure, such as increased blood pressure, decreased heart rate, and decreased conscious level?
- Conscious level decreases because of extra pressure on the reticular activating system.
- Blood pressure rises to get more oxygenated blood into the skull against the rise in ICP.
- Heart rate will initially increase to get oxygen into the brain but will then fall as the ICP continues to rise.
82
Julie, aged 19 years came off her motor bike 2 days ago and suffered what she thought was a minor head injury. After a initial recovery, however, she is now suffering from acute head ache and altered consciousness. Healthcare workers are concerned that she might have raised intracranial pressure due to a cerebral bleed.
What is the most likely reason for Julie's headache following the injury?
The larger cerebral arteries and the venous sinuses are very sensitve to pain, so any change in intracranial pressure creates pain and headaches
83
What is the sequence of the vertebrae, starting at the head and moving down the body?
Cervical > thoracic > lumbar > sacral > coccyx
84
What is the name of the first cervical vertebra on which the skull is attached?
Atlas
85
How many vertebrae in the spinal column?
33 vertebrae
86
What is the purpose of having an intervertebral disc between each of the vertebrae?
Acts as a shock absorber
87
As a person ages, the spinal vertebrae can degenerate. What can occur?
- Blood supply can diminish
- The intervertebral disc can dehydrate, losing its elasticity.
- Spinal cord compression can occur
88
What is meant by a 'slipped disc'?
The cartilaginous tissue between the vertebrae has bulged out
89
What is the definition to "...occurs when the spine is bent forwards exceeding the span of movement that is possible, eg hit in the stomach " ?
Hyperflexion
90
What is the definition to "...occurs when the person lands on their head or their feet and the force on landing travels upwards through the body and the spine, eg diving into swimming pools, catapulted over a car " ?
Axial
91
What is the definition to "...occurs when the body twists as the person lands " ?
Rotational
92
What is the definition to "...occurs when the spine is extended backwards, eg hit in the jaw and the head is forced backwards "?
Hyperextension
93
Jennie was thrown forward over the steering wheel in a road traffic accident.
What injuries are most likely to be causing the primary spinal injury Jennie potentially has?
Compression, stretching and shearing of the spinal cord
94
Mr Smith had significant problems with short-term memory consolidation during his illness.
What has a significant role in short-term memory consolidation?
Hippocampus
95
From your reading, you find that during the progression of Alzheimer’s disease, such as Mr Smith had, the dendrites of neurones show regression and loss. This is potentially related to the cognitive changes seen because:
Dendrites enable neurones to communicate with one another.
96
Mr Smith was a participant in a research study into the progression of Alzheimer’s disease. He recently underwent an MRI scan of his brain. Which two lobes of the cerebrum do you think showed the greatest loss of volume compared to the control participants who did not have Alzheimer’s disease?
Frontal and temporal lobes
97
As part of the research study, Mr Smith had consented to small histological tissue samples being taken of his brain following his death for microscopic examination. The sections showed high levels of plaque formation. Plaque formation in the brain is thought to occur as a result of:
Abnormal enzymic breakdown of B-amyloid associated protein.
98
During the early stages of his disease, Mr Smith was prescribed the medication “Aricept” to increase acetylcholine levels in the brain. Aricept acts by:
Blocking the enzyme Acetylcholinesterase that breaks acetylcholine down.
99
Name substances that are neurotransmitters?
- N-methyl-D-aspartic acid
- Glutamate
- Gamma-aminobutyric acid
- Acetylcholine
100
Which part of the brain is affected in Parkinson's disease, resulting in the fine tremor that is seen?
Basal ganglia
101
Mr Watts has a diagnosis of Parkinson's disease. What structures are seen in the neurons affected by Parkinson's disease in the brain?
Lewy bodies
102
What is dementia?
A progressive degenerative disease affecting the brain and nervous system
103
Name some forms of dementia.
Alzheimer's disease, vascular dementia, focal dementias, subcortical dementias
104
What is Alzheimer's characterised by?
A loss of brain cells with consequent brain shrinkage, and psychological symptoms that get worse as the disease progresses
105
What are the psychological symptoms at the mild stage of Alzheimer's?
Memory loss (semantic and episodic), problems thinking and making decisions
106
What are the psychological symptoms at the moderate stage of Alzheimer's?
Confusion, disorientation in time and space, poor judgement, personality changes, disturbed sleep patterns
107
What are the psychological symptoms at the severe stage of Alzheimer's?
Patients forget their own identity, don't recognise others, unable to communicate, loss of mobility, poor control over bodily functions
108
What happens to the brain in the early stages of Alzheimer's?
Glucose levels and neurotransmitters are reduced
108
What are beta-amyloid plaques?
Short fragments of beta-amyloid protein are released from the membranes of neurons, these accumulate as beta amyloid plaques and interfere with the functioning of other neurons
109
What is the role of tau?
Healthy neurons contain microtubules which transport nutrients, a protein called tau plays an important part in their functioning
110
What are neurofibrillary tangles?
Twisted strands of tau protein form tangles inside the cell, disabling the internal transport system and causing cell death
111
What happens when neurons die?
The brain shrinks and sulci and ventricles expand
112
Dementia has insidious onset... what does this mean?
It's hardly noticed at first
113
In which areas of the brain do patients of Alzheimer's show shrinkage before diagnosis?
In the anterior, inferior and medial temporal lobes
114
What do the frontal lobes do?
Control thought and behaviour
115
What may Alzheimer's patients' personality changes be related to?
A lack of cognitive control (frontal lobe atrophy)
116
What are seizures?
Sudden electrical disturbance in the brain
117
What happens with seizures?
excess of electrical activity = disruption of neurons activity = mixed or halted messages
118
What is an absence seizure?
Blanking out staring and unresponsive
Followed by rapid recovery
119
What is juvenile myoclonic epilepsy?
- tremors or "jitteriness"
- Often precedes a tonic-clonic seizure
120
What is a focal seizure?
Partial seizure
Characterised by the presence of an aura
Manifests as experiencing deja vu, making random noises, unusual posture, fiddling
121
What risks are associated with tonic-clonic seizures?
Loss of consciousness- uncontrolled fall without warning
Nighters risk of SUDEP (Sudden Unexpected Death in Epilepsy)
122
What are the risks associated with absence seizures?
Increased risk of a tonic seizure
Modest physiological effects
123
What are the risks associated with juvenile myoclonic seizures?
Sudden jerks - falls or injury
- associated with sleep deprivation
124
What are the general risks associated with living with epilepsy?
Risk of depression and anxiety
Driving risks
Risk of drowning
Risk of head trauma
Risk of falls
125
What are the signs and symptoms of increased intracranial pressure (ICP)?
Signs and symptoms of increased ICP include headache, vomiting, altered mental status, blurred vision, papilledema, and, in severe cases, coma or herniation.
126
What is the role of the meninges?
The meninges are protective layers of tissue that surround the brain and spinal cord. They consist of three layers: the dura mater, arachnoid mater, and pia mater, which help protect the central nervous system and maintain cerebrospinal fluid (CSF) circulation.
127
What is the pathophysiology of cerebrovascular disease?
Cerebrovascular disease involves conditions affecting blood flow to the brain, including ischemia (reduced blood flow), haemorrhage (bleeding), and other issues such as atherosclerosis, leading to strokes and other brain dysfunctions.
128
What is the Circle of Willis, and what role does it play?
The Circle of Willis is a network of blood vessels at the base of the brain that provides collateral circulation, ensuring blood flow to the brain if one vessel becomes blocked or narrowed.
129
What are venous sinuses, and what is their function?
Venous sinuses are large veins in the brain that collect deoxygenated blood and return it to the heart. They play a crucial role in draining blood from the brain and ensuring proper circulation.
130
What is autoregulation in cerebral blood flow?
Autoregulation refers to the ability of the brain's blood vessels to maintain a constant blood flow despite changes in systemic blood pressure, ensuring stable oxygen and nutrient delivery to brain tissue.
131
What are the types of intracranial haemorrhage?
Types of intracranial haemorrhage include:
- Epidural haemorrhage: bleeding between the dura mater and skull.
- Subdural haemorrhage: bleeding between the dura mater and arachnoid mater.
- Subarachnoid haemorrhage: bleeding between the arachnoid mater and pia mater.
- Intracerebral haemorrhage: bleeding within the brain tissue itself.
132
What is coning (brain herniation) in relation to intracranial pressure?
Coning or brain herniation occurs when increased intracranial pressure causes part of the brain to be forced out of its normal position, often through the foramen magnum. It is a life-threatening condition that can lead to brain death.
133
How can changes in cerebrospinal fluid (CSF) flow create intracranial pressure issues?
Changes in CSF flow, such as in hydrocephalus (excess CSF), can increase intracranial pressure, as the accumulation of CSF within the ventricles or subarachnoid space leads to compression of brain tissue.
134
What is the function of the cerebral cortex?
The cerebral cortex is responsible for higher brain functions such as perception, thought, decision-making, voluntary movement, and language processing. It is divided into different regions that specialize in different functions, such as the frontal, temporal, parietal, and occipital lobes.
135
How is information processed in the brain?
Information processing in the brain involves sensory input being received, interpreted, and responded to. It occurs in specialized areas of the brain like the sensory cortices, association areas, and motor areas, with the brain's neurons transmitting electrical signals and forming neural networks to process and store information.
136
What is the role of memory, and what is neuroplasticity?
Memory allows the brain to store, retrieve, and use information.
Neuroplasticity refers to the brain's ability to reorganize itself by forming new neural connections throughout life in response to learning, experience, or injury.
137
What are excitatory and inhibitory neurotransmitters?
Excitatory neurotransmitters (e.g., glutamate) increase the likelihood of a neuron firing an action potential, while inhibitory neurotransmitters (e.g., GABA) decrease the likelihood of neuron firing, helping to regulate the brain's activity and maintain balance.
138
How does alcoholism relate to substance abuse?
Alcoholism is a form of substance abuse where individuals develop a dependence on alcohol, often leading to harmful effects on the brain's function, including memory loss, impaired decision-making, and disrupted neurotransmitter balance, which exacerbates addictive behavior.
139
What is the role of tau protein in dementia?
In Alzheimer's disease, tau protein becomes abnormally phosphorylated, causing neurofibrillary tangles to form inside neurons. This disrupts cellular function and contributes to cognitive decline.
140
What are Lewy bodies, and how are they related to dementia?
Lewy bodies are abnormal clumps of the protein alpha-synuclein found in neurons. They are a hallmark of Lewy body dementia, a type of dementia that leads to progressive cognitive decline, motor symptoms, and visual hallucinations.
141
What are neurofibrillary tangles, and how do they affect the brain?
Neurofibrillary tangles are twisted tangles of the tau protein found inside neurons. In Alzheimer's disease, these tangles disrupt normal cell function, leading to neuronal death and contributing to the cognitive symptoms associated with dementia.
142
What is the pathophysiology of Parkinson's Disease?
Parkinson's disease is a neurodegenerative disorder caused by the loss of dopamine-producing neurons in the substantia nigra.
This results in decreased dopamine levels, which can cause motor symptoms such as tremors, rigidity, bradykinesia, and postural instability. It can also cause non-motor symptoms like cognitive decline and mood changes.
143
What is the pathophysiology of epilepsy and seizures?
Epilepsy involves abnormal electrical activity in the brain, often due to issues with neurotransmitter balance or structural changes in the brain.
During a seizure, neurons fire synchronously inappropriately, leading to uncontrolled movements, altered consciousness, or sensory disturbances.
144
What is the pathophysiology of ADHD (Attention Deficit Hyperactivity Disorder)?
ADHD is associated with an imbalance in neurotransmitters, especially dopamine and norepinephrine. Dysfunction in brain regions like the prefrontal cortex, which controls attention and impulse control, leads to symptoms such as inattention, hyperactivity, and impulsivity.
145
What does norepinephrine do?
Norepinephrine is a neurotransmitter that plays a key role in the body's "fight or flight" response.
It increases heart rate, blood pressure, and blood flow to muscles. It also influences attention, arousal, and mood regulation.
In the brain, it helps with focus, alertness, and response to stress.
146
What is the pathophysiology of autism?
Autism spectrum disorder (ASD) involves abnormalities in brain development, particularly in areas related to social communication, sensory processing, and behavior.
Neurodevelopmental differences in synaptic formation, neurotransmitter imbalances, and genetic factors contribute to the symptoms of ASD.
147
What is the pathophysiology of mood disorders (e.g., depression and bipolar disorder)?
Mood disorders are often linked to imbalances in neurotransmitters like serotonin, dopamine, and norepinephrine. In depression, there is typically reduced activity of these neurotransmitters, while bipolar disorder involves shifts between depression and mania, with fluctuations in neurotransmitter levels and brain activity.
148
What is the pathophysiology of hydrocephalus?
Hydrocephalus occurs when cerebrospinal fluid (CSF) accumulate in the brain's ventricles, often due to obstruction, impaired absorption, or overproduction of CSF.
This increased pressure on the brain can lead to symptoms such as headaches, nausea, and cognitive decline.
149
What is the pathophysiology of cerebrovascular accidents (stroke)?
A stroke occurs when there is an interruption in the blood supply to the brain, either through blockage (ischemic stroke) or bleeding (hemorrhagic stroke). This leads to tissue damage due to lack of oxygen and nutrients, resulting in neurological deficits such as paralysis, speech difficulties, and cognitive impairments.
150
What pathophysiological changes are associated with spinal cord damage due to the ageing process?
As individuals age, spinal cord function naturally declines due to neuron loss, reduced blood flow, and changes in the structure of nerve cells.
This can lead to slower reflexes, reduced coordination, and an increased risk of injury. Degenerative conditions like osteoarthritis and disc degeneration may also contribute to spinal cord issues in older adults.
151
What pathophysiological changes occur in the spinal cord due to trauma?
Trauma to the spinal cord can cause direct physical injury to nerve fibres, leading to inflammation, swelling, and disruption of nerve transmission.
This can result in temporary or permanent loss of sensation, motor function, and autonomic function below the injury site.
Axonal damage and oedema contribute to further impairment.
152
What are the pathophysiological changes associated with spinal cord injury?
Spinal cord injury leads to a cascade of pathophysiological events, including primary injury (direct damage to nerve fibres) and secondary injury (inflammation, ischemia, and oxidative stress).
This results in cell death, demyelination, and loss of motor, sensory, and autonomic functions. The level of injury determines the extent of dysfunction.
153
What changes occur in the spinal cord due to vertebral column injury?
Vertebral column injury, such as fractures or dislocations, can compress the spinal cord, causing mechanical damage, ischemia, and inflammation.
This compression reduces blood flow and impedes neural transmission, leading to sensory and motor pathway dysfunction.
In severe cases, it can result in paraplegia or quadriplegia (paralysis)
154
What pathophysiological changes occur in the spinal cord due to disease processes?
Disease processes such as infections (e.g., meningitis), autoimmune diseases (e.g., multiple sclerosis), or genetic conditions (e.g., amyotrophic lateral sclerosis) can cause progressive damage to the spinal cord.
This leads to demyelination, axonal loss, and impaired neural function, gradually losing motor and sensory abilities.
155
What is paralysis?
Paralysis is losing the ability to move or feel in part or most of the body, typically due to nerve damage or injury.
156
What is kyphosis?
Kyphosis is an abnormal curvature of the spine, often referred to as a "hunchback," where the upper back becomes excessively rounded.
157
What is quadriplegia?
Quadriplegia, also known as tetraplegia, is the paralysis of all four limbs (both arms and both legs), typically caused by a spinal cord injury at the cervical level.
158
What is scoliosis?
Scoliosis is a sideways curvature of the spine, usually in an "S" or "C" shape, that can occur during growth spurts before puberty.
159
What is paraplegia?
Paraplegia is the paralysis of the lower half of the body, including both legs, often resulting from a spinal cord injury in the thoracic, lumbar, or sacral regions.
160
What is lordosis?
Lordosis is an exaggerated inward curve of the spine, typically in the lower back, which can cause a swayback appearance.
161
What is hemiplegia?
Hemiplegia is paralysis on one side of the body, often resulting from a stroke or brain injury affecting one hemisphere of the brain.
162
What is the physiological basis of pain and related stress?
Pain is caused by activating nociceptors (pain receptors) in response to tissue damage or harmful stimuli.
The brain processes these signals, and stress can amplify pain perception by increasing the release of stress hormones (e.g., cortisol), leading to heightened sensitivity and discomfort.
163
What are the ascending and descending pathways of pain signals in acute pain?
The ascending pathway carries pain signals from nociceptors to the spinal cord and then to the brain.
The descending pathway involves brain areas, such as the brainstem, which modulate pain by either amplifying or inhibiting pain signals through neurotransmitters like serotonin or endorphins.
164
What are nociceptors, and how is pain perceived?
Nociceptors are specialized sensory receptors that detect harmful stimuli (thermal, mechanical, or chemical) and initiate the sensation of pain.
The pain signals are transmitted to the spinal cord and brain, where they are processed and perceived as pain.
165
How are chronic pain and stress interrelated?
Chronic pain can lead to prolonged stress by activating the body's stress response system, while stress can worsen the perception of pain.
This creates a feedback loop where chronic pain exacerbates stress, and stress increases the intensity of pain, making it harder to manage.
166
Define this terminology used in pain.
- Nociception
- Hyperalgesia
- Allodynia
- Somatic pain
- Visceral pain
- Nociception = the process of detecting pain.
- Hyperalgesia = increased sensitivity to - pain.
- Allodynia = pain from stimuli that typically do not cause pain.
- Somatic pain = pain from skin, muscles, or joints.
- Visceral pain = pain from internal organs.
167
What is the pathophysiology of headaches?
Headaches are caused by various factors such as tension, inflammation, or changes in blood flow within the brain.
In tension headaches, muscle tightness causes pain. In migraines, abnormal brain activity affects blood vessels and pain pathways, often leading to nausea, sensitivity to light, and throbbing pain.
168
What is the face drawing to remember the function of the cranial nerves?
1 = Olfactory
2 = Optic
3 = Oculomotor
4 = Trochlear
5 = Trigeminal
6 = Abducens
7 = Facial
8 = Vestibulocochlear
9 = Glossopharyngeal
10 = Vagus
11 = Spinal accessory
12 = Hypoglossal
169
Which organ receives the sensory information going into the brain before distributing it around the brain?
Thalamus
170
What substance opens channels in the synapse to allow the impulse to cross to the next neuron?
Excitatory neurotransmitters
171
During a seizure, clusters of neurons in the brain are affected and send out multiple repeated signals.
Which neurotransmitter is the main excitatory neurotransmitter used in the brain?
Glutamate
172
In what order does the impulse cross the synapse?
1. Action potential reaches the synapse and is encapsulated in a vesicle containing neurotransmitters,
2. Vescicles release neurotransmitter,
3. Neurotransmitter crosses synapse,
4. Neurotransmitter binds to the receptor
5. Impulse passes into the afferent neurone
173
Sahil is prescribed a benzodiazepine 'midazolam' as an emergency medication when seizures continue.
Which neurotransmitter is supported by giving an anticonvulsant such as a benzodiazepine?
Gamma-aminobutyric acid (GABA)
174
Fidel’s left leg started to jerk, followed quickly by him losing consciousness and an uncontrolled jerking of all limbs.
What is happening?
(Seizures)
The seizure began with a partial seizure, progressing to a full tonic-clonic seizure.
175
Following emergency medication, Summer's seizure activity stops, and she enters a post-ictal phase.
What needs to happen before Summer can recover consciousness?
The reticular activating system needs to restart functioning.
