Neurological disorders and diseases Flashcards
what is consciousness?
state of awareness of ones self and the environment and the ability to react to external stimuli
what is arousal?
state of awakeness and all conscious thought
what is awakeness?
all cognitive function
what is brain death?
when the brain can no longer maintain internal homeostasis
What are some of the brain death criteria?
- un responsive coma
- no spontaneous respiration (apnea)
- no brainstem function
What is Cerebral death?
- irreversible coma - death of both hemispheres exclusive of brainstem and cerebellum.
- no behavioural or environmental responses
- no respiratory function can be maintained
In Cerebral brain death can internal homeostasis be maintained?
Yes
When people survive comas, what is life like?
- remain in coma
- vegetative state - if they arise awareness is absent
- progress into minimal conscious sate (MCS)
What is selective attention?
ability to select from available, competing environmental and internal stimuli
what is sensory inattentiveness? what are the two types
person is able to recognize sensory, but ignores it.
2 types: Extinction & Neglect Syndrome
what is selective attention deficit? Where is it mediated?
the inability to focus on stimuli. Can be temporary, permanent or progressive.
Mediated by the midbrain and thalamus and parietal structures
What is Amnesia? what are the types?
failure to recognize the form or nature of objects.
Retrograde - past thoughts are lost
Anterograde - new memories cant be formed
what is an example of an attention deficit?
ADHD
What is Dementia? What are some examples of memory losses associated with dementia?
Progressive failure of many cerebral functions including intellectual processes.
Losses: orientation, memory, language, judgement, decision making
What are mechanisms of Dementia?
neuron degeneration, brain tissue compression, atherosclerosis, brain trauma
What is atherosclerosis?
Cardiac disease
What is Alzheimers Disease? 3 types?
irreversible, progressive brain disorder that slowly destroys memory and thinking skills and, eventually, the ability to carry out the simplest tasks types: Early onset familial Late onset non hereditary sporadic Early onset (rare)
What causes Alzheimer disease?
Plaque build up in the brain due to excessive amyloid protein and neurofibrillary tangles
What do microtubules do in the nervous system?
transport nutrients and organelles from soma to tip of axon
What are Seizures?
sudden, uncontrolled, abnormal discharges of cortical neurons. can cause changes in your behavior, movements or feelings, and in levels of consciousness.
what are some causes of seizures?
cerebral brain leisons, biochemical disorders, trauma, epilepsy
What is epilepsy?
reoccurring seizures - thought to be genetic mutations interacting with environmental factors
Seizures can be ______ or ________.
generalized or focal
What are convulsions?
tonic-clonic (jerky, contract - relax) movements associated with seizures
How are Seizures categorized?
clinical manifestations, site of origin, EEG correlates and response to therapy
What is increased intracranial pressure? (IIPC) examples?
caused by increase in intracranial content
tumour growth, edema, excessive CSF or haemorrhage.
What is Cerebral Edema? What are the types of edema (3)?
increased in fluid within the brain - intracellular or extracellular
types:
Vasogenic - extracellular accumulation of fluid resulting from disruption of the blood-brain barrier (BBB) - caused by increased permeability of capillaries in brain
Cytotoxic - cell swelling by intracellular build accumulation
Interstitial - seen with non communicating hydrocephalus. caused by transependymal movement of CSF from ventricles into extracellular space of brain tissues
What is Hydrocephalus?
excess fluid in ventricles, sub arachnoid space or both. imbalance of how much CSF is produced and how much is absorbed.
Why could there be poor absorption of CSF in the brain?
inflammation of tissue or obstruction
what is hypotonia?
an abnormally low level of muscle tone.
What is hypertonia?
an abnormally high level of muscle tone or tension.
what is spasticity?
certain muscle only constantly contract and causes stiffness of muscle
what is paratonia?
inability to relax muscles during assessment of muscle tone
what is dystonia?
muscle contract uncontrollably - one muscle or whole body
What is rigidity?
inability to be changed or adapted shape
What is Huntingtons Disease?
autosomal dominant hereditary degenerative disorder
also known as chorea. Degeneration of basal ganglia (caudate nucleus) and cerebral cortex. Depletion of GABA
What is Parkinsons Disease?
severe degeneration of basal ganglia (corpus striatum) involving dopaminergic nigrostraital pathway.
What hormone is depleted in Parkinsons disease?
Dopamine in basal ganglia
what is Brady Kensisa? how is it related to huntingtons disease?
slow movement, postural disturbances, autonomic and neuroednocrine symptoms
What is Amyotrophic Lateral Sclerosis ?
Neuro-degenerative disorder involving upper and lower motor neurons
What is Amyotrophic Lateral Sclerosis cause?
progressive muscle weakness, decrease in muscle mass and normal gate patterns
What is Traumatic brain injury?
alteration in brain function due to external force
What is primary TBI?
direct impact
focal or diffuse
focal - closed blunt brain trauma or open penetrating
diffuse - non direct trauma, brain shaking
What is secondary TBI?
indirect consequence of primary injury
more common
occurs days or hours after initial trauma
can be open injury - fractured skull
What is focal brain injury?
observable brain lesion. force typically produces contusions.
What is a epidural hematoma?
bleeding occurs between the tough outer membrane covering the brain (dura mater) and the skull.
what is a subdural hematoma?
collection of blood outside the brain. increases pressure on brain
What is a intracerebral hematoma ?
occurs when blood pools in the brain
What is a hematoma ?
clotting of blood within the brain
What is a diffuse brain injury?
axonal damage due to acceleration/deceleration or rotational forces
What is a mild concussion
immediate but transitory clinical manifestation
What is a classic cerebral concussion?
loss of consciousness for < 6 hours with amnesia and confusion lasting for hour or days
What is a secondary brain injury?
indirect result of primary brain injury, develops in intra or inter cranial responses to previous injury –> causing further neuronal death
What are complications of TBI?
post concussion syndrome & post traumatic seizures
What is a primary spinal cord Injury?
occurs with initial mechanical trauma and immediate tissue destruction. inadequate mobilization after injury. damage to neuron from shearing.
What is a secondary cord injury?
pathological cascade of events that begins immediately after injury and continues for weeks
What is vertebral injury?
injury of vertebral and neural tissues as a result of compressing, pulling and shearing forces
What is a hypertension injury?
stretching and disruption of intervertebral disks
What is a flexion injury?
wedge fracture - caused by flexion
What is a compression injury?
compression of vertebral disks
Flexion rotation injury?
injury on vertebral disks due to rotation
What is spinal shock?
develops immediately after injury. normal activity ceases at and below level of injury. complete loss of reflex function below the lesion
What is Neurogenic shock?
occurs within cervical or upper thoracic spinal cord. injury about t5 and is caused by the absence of sympathetic activity and unopposed parasympathetic tone mediated by the vagus nerve.
what is autonomic hyper-reflixia (dysreflexia) ?
massive, uncompensated cardiovascular response to stimulation of sympathetic nervous system. spinal cord injury at T6 and above. complete loss of reflex function below the lesion
what is Cerebral-vascular disorder?
cerebral vascular accidents or strokes.
what is the cause of stroke? what is the result?
Cause: abnormal blood flow in the brain.
Result: disability and neuronal disfunction
what is transient ischemic stroke
occurs when there is an obstruction to arterial blood flow to the brain from thrombus formation. smaller episodes of neuro disfunction - no longer than an hour.
what is a hemorrhagic stroke?
third most common. when blood from an artery begins bleeding into the brain. This happens when a weakened blood vessel bursts and bleeds into the surrounding brain. Pressure from the leaked blood damages brains cells, and, as a result, the damaged area is unable to function properly.
what is a migraine?
familial, eposiodic disorder whose marker is a headche but is repeated. can last for 4-72 hours and typically more common in women age 22-55.
Migraines are worsened by __________.
movement
what is tension type head ache?
most common, mild to moderate bilateral headache with a sensation of tight band or pressure. occurs 15 days a month for several hours or several days
how can you diagnosis a migraine? what are the symptoms?
unilateral, throbbing, nausea, vomitting, photophobia or phonophobia
What is Meningitis? what are the three types?
infection of the meninges Types: fungal - least common bacterial - infection of the pia, arachnoid and sub archnoid space viral - limited to meninges
what is Multiple sclerosis?
acquired autoimmune disease that is progressive, inflammatory demyelinating disorder of the CNS.
what is Guillian-barre syndrome?
acquired inflammatory disease demyelinating disorder of the periphery nerves. Acute, onset ascending motor paralysis. Involves humoral and cellular immunological reactions
What is Myasthenia Gravis?
acquired chronic autoimmune disease. IgG antibodies attack ach receptors and blocks binding. defect in nerve impulse transmission at the post synaptic membrane of muscular junction
what are the symptoms of Myasthenia Gravis?
weakness, fatigue of muscles and eyes and throat - causing diplopia and difficulty swallowing and chewing.
What is a brain tumour?
tumour in the brain, can be either primary or metastatic (extracerebral tumours)
What are primary brain tumour (gliomas)? what are the 3 types?
originate from brain substance including neuroglia, neurons and cells of blood vessels.
3 types:
astrocytoma - They originate in a particular kind of glial cells.
oligodendroglioma - originate from the oligodendrocytes of the brain or from a glial precursor cell.
Ependymoma - is a tumour that arises from the ependyma, a tissue of the central nervous system
what are extracerebral tumours (metastatic)? what are the 3 types?
inside or outside of the brain
3 types?
Meningioma - tumor that forms on membranes that cover the brain and spinal cord just inside the skull
nerves sheath tumour (neurofribroma) - abnormal growth within the cells of this covering
metastatic brain tumours - begins elsewhere in the body and spreads to the brain
what are the two types of spinal cord tumours?
intramedullary and extramedullary
