tremor (oscillations; alternating contract/relax of agonist/antagonist muscles) (action or resting)
postural tremor (evident when arms are stretched out or when wrists are dorsiflexed; tremor may be absent when limb is supported; feet almost never involved)
True or False: Parkinsonism is associated with resting tremors.
True
True or False: Certain toxins (e.g. MPTP) and drugs (Phenothiazines, metoclopramide) can cause symptoms similar to those seen with Parkinson's Disease.
True
What are some typical syptoms and signs of Parkison's Disease?
resting tremors that improve with movement
bradykinesia (slowness of movement)
rigidity
balance problems
decrease in substantia nigra (midbrain)
Lewy bodies (aggergates of protein) in neurons in brain
(Parkinson's disease is not the same as Parkinsonism)
What is the neurotransmitter transmitted in the nigrastriatal fibers? Where do they run?
dopamine
the nigrastriatal fibers run from the sustantia nigra to the striatum of the basal ganglia
What are the characteristics of Huntington's Disease?
autosomal dominant
mutation in Huntington gene (CAG expansion)
no present effective treatment
symptomatic treatment for chorea and dementia (e.g. neuroleptic drugs such as haloperidol)
sx: dementia, chorea, athetosis, enlarged frontal horns of lateral ventricales in brain, cortical atrophy, atrophy of caudate nuclei
What is the typical treatment for Parkinson's Disease?
free Cu (total Cu: 3x ceruloplasmin) is high (>15-20 ug/dl)
24 hr urine Cu is high
sx: increasing dystonia, chorea, and/or tremors; Kaiser-Flasher ring (copper ring in inner layer of cornea); hyperintensities in basal ganglia (MRI image); copper deposits in liver, kidneys, and cornea
What would you NOT expect to see on an MRI scan of a brain from a person with advanced Huntington's Disease?
C. enlarged caudate nuclei
True or False: Fasciculations are symptomatic of cervical spondylosis with rediculopathy and with amyotrophic lateral sclerosis (ALS)
True
True or False: Myokymia is often decreased or absent in a patient with multiple sclerosis.
False
What type of consequences might you see with a lesion in the central tegmentum of the brainstem?
involuntary movements
palatal myoclonus (jerks of pharyngeal/palatal muscles)
True or False: Hemifacial spasms are often caused by pressure of an artery (posterior inferior cerebellar artery) that is located close to the root entry nerve of the ipsilateral cranial facial nerve (CN VII).
True
True or False: Hemifacial spasms are different from tics because patients with tics often have the ability to concentrate and inhibit the movements while patients with hemifacial spasms often do not have this ability.
True
What is FALSE about tics?
A. they often present with slow, gradual onset
All of the following are potential symptoms of which involuntary movment disease?
multiple motor and vocal tics
symptoms usually appear between the ages of 2-25 years old
patients may snort, grimace, hiccough or emit explosive sounds
corprolalia (expression of vulgar words)
Tourette's syndrome
Which statment about myoclonus is FALSE?
C. myoclonus is not a possible consequence of uremia
Which of the following can cause diseases/conditions with myoclonus?
F. all of the above
a. mutations in mitochondrial gene --> MERRF (myoclonic epilepsy with red ragged fibers)
b. degenerative disorders of cortical neurons --> progressive myoclonic epilepsy; Baltic myoclonus
c. anoxic-ischemic damage to CNS, especially serotoninergic centers --> generalized myoclonus
d. metabolic conditions (e.g. uremia)
e. encephalitis
True or False: Intentional tremors are commonly associated with damage to the cerebellar outflow systems.
True
What is Benedikt's syndrome and what causes it?
Benedikt's syndrome: severe intentional tremors in extremities because of damage to contralateral red nucleus in midbrain
cause: infarct due to occlusion of a branch of the basilar artery
What symptom would be caused by an infarction in the posterior cerebral artery resulting in damage to the subthalamic nuclei?
contralateral hemiballismus
Chorea is generally associated with damage to which part of the brain? What is an example of a disease associated with chorea?
basal ganglia, esp. striatum
Huntington's disease
Which condition is associated with basal ganglia damage secondary to kernicterus (bilirubin disorder)?
athetosis (slow, twisting, writhing movements; alternation of flexion/extension, supination/pronation)
What are some examples of focal dystonias?
blepharospasm
writer's cramp
spasmodic torticollis
A likely location of a single lesion which causes both left facial and right arm/leg paralysis (alternating hemiplegia) is in the:
leftside pons
At what level is the unilateral lesion that would cause the following: Loss of pain and temperature sensation on ONE side of the body AND loss of vibration and position sense on the OPPOSITE side of the body.
spinal cord
At what level would the unilateral lesion be to cause the following: Loss of fine touch and vibration sense on ONE side of the body AND fasciculations of the tongue on the side OPPOSITE to the paralysis.
medulla
At what level would the unilateral lesion be to cause the following: Weakness and hyperreflexia on ONE side of the body AND a homonymous hemianopsia IPSILATERAL to the paralysis.
cortex
At what level would the unilateral lesion be to cause the following: Loss of pain and temperature sense on ONE side of the body AND some loss of pain and temperature sense on the OPPOSITE side of the face.
medulla
At what level would the unilateral lesion be to cause the following: Weakness and hyperreflexia on ONE side of the body AND loss of pupillary accommodation in the CONTRALATERAL eye.
pons
Myokymia is associated with damage to what part of the nervous system?
peripheral motor nerve
Fasciculations are associated with damage to which part of the nervous system? What diseases are associated with fasciculations?
spinal cord; nerve roots; anterior horn cells
(i.e. lower motor neurons)
cervical spondylosis, ALS
Intentional tremors are associated with damage to which part of the nervous system? What is an example of a disease associated with intentional tremors?
cerebellum (esp. dentate nucleus)
Benedikt's syndrome
Resting tremors are associated with damage to which part of the nervous system?
substantia nigra
Slow speech with telegraphic content, impaired writing, dysarthria, and hemiparesis are characteristics of which type of aphasia?
nonfluent aphasia
When a person has impaired comprehension and can speak in complete sentences but often has paraphasic errors and jargonisms, they are said to have which type of aphasia?
fluent aphasia
Anomias, or disorders of naming, are associated with damage to which part of the brain?
(dominant) temporal lobe
What type of aphasia is associated with damage to the arcuate fasciculus and what are its particular symptoms?
damage to the arcuate fasciculus --> conduction aphasia
disorder of repitition (e.g. "no ifs, ands, or buts" said repeatedly)
Infarction or transection of the anterior corpus callosum may lead to what?
apraxia (inability to carry out learned, purposeful movements) of LEFT extremities
A patient presents with "alexia without agraphia" (unable to read but able to write) and right homonymous hemianopsia but is able to name and recognize objects. What areas of the brain would you suspect to be damaged? If the brain damage resulted from arterial occlusion, which artery is most likely involved?
damage: left visual cortex; posterior corpus callosum
artery: posterior cerebral artery
Which is FALSE about memory loss (i.e. amnestic syndrome)?
C. damage to the medial thalamus does not usually result in memory loss
What are some common causes of isolated amnestic syndrome?
thiamine deficiency (Wernicke-Korsakoff syndrome)
bilateral infarcts of medial temporal lobes
bilateral infarcts of dorsomedial thalamus
bilateral temporal lobectomy
carbon monoxide poisoning
herpes simplex encephalitis
temporal lobe contusions
thalamis tumors
vascular complications (e.g. embolus to "top of basilar")
trauma
What are some general symptoms associated with lesions in the right hemisphere?
anomic temporal lobe: comprehension normal, repitition normal
isolation areas: comprehension impaired, repitition normal
What type of brain damage results in "general aphasia" and what are some associated symptoms?
general aphasia: damage to both Broca's (frontal lobe) and Wernicke's areas (posterior superior temporal lobe)
symptoms: nonfluent aphasia combined with loss of comprehension and repetition, possibly writing difficulties
What are the cortical areas involved in speech and speech perception?
facial area of motor cortex
Broca's Area (operculum of frontal lobe)
Wernicke's Area (posterior superior temporal lobe)
transverse temporal gyrus
planum temporale
angular gyrus
visual association area
visual cortex (parietal lobe)
What is the correct sequence (first to last) of the cortical areas involved in naming a seen object?
A. visual cortex, angular gyrus, Wernicke's area, Broca's area, motor
cortex (facial area)
What is the correct sequence (first to last) of the cortical areas involved in understanding the spoken name of an object?
C. transverse temporal (Heschl's) gyrus, Wernicke's area, angular gyrus, visual association area
True or False: The visual association cortex is involved in naming a seen object; it is not involved in understanding the spoken name of an object.
False
Electrical stimulation of the nulcei in the left thalamus results in what types of behavioral disruption?
interuption of speech
inability to name objects
A patient who has undergone a surgery to sever the corpus callosum will not be able to readily name an object that is placed in which half of the visual field?
left visual field
(the right cerebral hemisphere, which would "identify" the object in the left visual field, cannot communicate with the language centers in the left cerebral hemisphere)
What are the three basic types of memory and how are they each tested?
immediate recall: repeat numbers, recall names of objects
short-term memory: recall names of objects or events of the recent past even after a distraction
long-term memory: recall events remote in time
Thiamine deficiency related to amnestic syndromes is often associated with damage to which particular part of the diencephalon?
mammillary bodies (hypothalamus)
What are some major cortical and subcortical structures that are affected by an occlusion (e.g. thrombus, embolus) in the posterior cerebral artery?
amygdala
amygdaloid nuclei
hippocampus
uncus
parahippocampal cortex
What is the medical definition of a seizure?
abnormal, excessive, paroxysmal (sudden and transient), synchronous discharge of a population of neurons, with a change in behavior and/or perception
What are the phases of an epileptic's life?
aura: brief period at start of seizure
ictus: sequence of events that make seizure
postictal: period immediately following seizure
interictal: all the rest of epileptic's life
What are the different types of generalized seizures?
tonic-clonic (grand mal)
absence-petit mal
myoclonic
atonic
Which cerebral lobe is the most common origination site for focal seizures?
temporal lobe
True or False: Any process that cuases destruction or irritation of the cerebral cortex can lead to a focal seizure.
True
How do the EEg's of a generalized seizure and a focal seizure compare?
generalized seizure: simultaneous discharge can be seen over the entire brain
focal seizure: abnormal electrical dishcarge is seen in just one area of the brain, it may spread to other areas
What marking on an EEG is diagnostic of epilepsy?
interictal epileptiform discharge
(paroxysmal depolarizing shift, PDS)
What is the PDS (paroxysmal depolarizing shift) and what are some possible mechanisms?
PDS: underlies interictal epileptiform discharge; synchronization of electrical activity in many neurons