| [WinFlash] Q1=What is the general role the basal ganglia play in motor activity? A1=* Translates the desire to move into action ^* Planning, initiation, and termination of movements, especially those with a complex cognitive dimension. Q2=Be able to identify and label components of the basal ganglia on a diagram. A2=* Striatum (caudate nucleus and putamen) (aka corpus striatum, neostriatum) ^* Lenticular nucleus (putamen and globus pallidus) ^* Globus pallidus (internal segment = medial segment; external = lateral) (aka pallidum) ^* Substantia nigra (pars compacta and pars reticulata) ^* Subthalamic nucleus ^* (Also part of the basal ganglia circuitry are the neocortex, ventral anterior, ventral lateral, and centromedian nuclei of the thalamus) Q3=What are the primary afferent structures of the basal ganglia, the major sources of inputs to the afferent structures, and the neurotransmitters involved? A3=* Striatum is primary afferent structure ^* Inputs to striatum: neocortex (except primary visual and auditory cortices); substantia nigra pars compacta; and centromedian nucleus of the thalamus ^* Neurotransmitters: neocortex and thalamus = excitatory glutamate; substantia nigra = dopamine (excitatory and inhibitory) Q4=What is the direction of information flow through the basal ganglia? A4=* Striatum project to internal and external globus pallidus segments and project to substantia nigra pars reticulata ^* External globus pallidus project to subthalamic nucleus ^* Subthalamic nucleus project to internal globus pallidus Q5=What are the primary efferent structures of the basal ganglia and their neurotransmitters? A5=* Internal segment of globus pallidus and substantia nigra pars reticulata project to centromedian, ventral anterior, and ventral lateral thalamic nuclei, which then project to the pre-central gyrus and frontal lobe. ^* Neurotransmitters: internal globus pallidus = inhibitory GABA; substantia nigra = GABA Q6=What are major diseases of the basal ganglia and the consequent changes in basal ganglia circuitry and function? A6=* Huntington's - bilateral degeneration of striatal neurons; hyperkinetic and eventually distonia; autosomal dominant gain-of-function mutation ^* Parkinson's - bilateral substantia nigra degeneration; hypokinetic Q7=What are various basal ganglia diseases? A7=o General = movement disorders ^o Hyperkinetic = involuntary, spontaneous, uncontrollable, and relatively rapid ^o Hypokinetic = inability or slowness to initiate voluntary movements; increased muscle tone, paucity of spontaneous movements ^o Distonia = spontaneous assumption of unusual fixed postures lasting seconds to minutes Q8=What are the four basal ganglia fundamentals from Haines? A8=o Damage to, or disorders affecting, the basal ganglia lead to movement disorders and possibly changes in cognition, perception, and mentation. ^o Anatomically and functionally segregated into parallel circuits that process different types of information. ^o Function primarily through disinhibition (release of inhibition). ^o Diseases of the basal ganglia can be described as disruptions of the neurochemical interactions between basal nuclei. Q9=What are the definitions of the following terms: bradykinesia, rigidity, tremor, postural instability, chorea, athetosis, ballism, dystonia, tics, and tardive disorders? A9=* Bradykinesia - extreme slowness of movements and reflexes ^* Rigidity - resistance to passive movements (by examiner) ^* Tremor - rhythmic, regular, involuntary movement, usually of the limb ^* Postural instability - tendency to fall due to delayed proximal relfexes ^* Chorea - disease featuring involuntary, uncontrollable, purposeless movements of body and face, often with marked incoordination of the limbs ^* Athetosis - marked by continuous slow movements, expecially of the extremities; related to chorea, but with more writhing, sinuous movements ^* Ballism - extreme proximal chorea with characteristic swinging, jerking limb movements ^* Dystonia - disordered fixed postures of limbs ^* Tics - involuntary movements or vocalization characterized by brief, frequent, irregular, and purposeless contractions of several functionally related muscle groups ^* Tardive disorders - twitching of the face and tongue and involuntary motor movements of the trunk and limbs, due to prolonged use of antipsychotic drugs Q10=What are the cardinal features of Parkinsonism? A10=* Tremor, rigidity, bradykinesia, impaired postural reflexes (40% get dementia) Q11=What is the primary differential diagnosis of Parkinson's disease? A11=* Infectious: von Economo's encephalitis, a sequelae only experienced during great influenze epidemics, can cause a Parkinson-like syndrome ^* Vascular: ischemic injury to substantia nigra pars compacta ^* Drug-induced: reserpine, alpha-methyl dopa, some antipsychotics ^* MPTP use: homemade Demerol derivative was actually MPTP, which is converted to MPP+ by MAO, which leads to substantia nigra death ^* Other: benign essential tremor, progressive supranuclear palsy, multisystem atrophy, olivopontocerebellar atrophy Q12=What are the cardinal features of essential tremor? A12=* Postural and terminal movement (e.g. writing, holding a spoon, etc) tremor most prominent in the upper extremities ^* Begins unilaterally, eventually bilateral because it gets progressively worse ^* PET shows overly-excited cerebellum ^* Treatment: beta-blockers, anticonvulsants, surgery to destroy the VIM thalamus to destroy connection to cerebellum Q13=What are the cardinal features of Huntington's disease? A13=* Personality change, chorea, dementia, dysarthria, abnormal eye movements, athetosis, dystonia, rigidity Q14=What are the cardinal features of Wilson's disease? A14=* Dystonic hands and face, tremor, dysarthria, rigidity ^* Young person with dystonia has WD unless proven otherwise Q15=What are the cardinal features of Ballism? A15=* Involuntary movement affecting the proximal limb musculature, manifested as jerking, flinging movements of the extremity ^* Usually one-sided = hemiballismus Q16=What are the cardinal features of Tourette's syndrome? A16=* Multiple motor and/or phonic tics which fluctuate in type and frequency, present for more than one year ^* Tic types: face > head/shoulder > arm >> leg/trunk Q17=What are the cardinal features of dystonias? A17=* Fixed postures of limbs or muscle groups ^* Types: generalized - childhood onset; focal/segmental - adult onset Q18=What are the cardinal features of tardive disorders? A18=* "the great mimic" ^* dyskinesia (usually oral/buccal - chewing, tongue thrusting), chorea, dystonia, tics, akathisia (Stedman's - akathisia = syndrombe characterized by an inability to remain in a sitting posture, with motor restlessness and a feeling of muscular quivering) ^* caused by long-term neuroleptics; limit dosing to prevent, can't do much when they start Q19=What are the pathologies of Ballism and Parkinson's, Huntington's, and Wilson's diseases? A19=* Ballism - caused by a lesion of, or near, the contralateral subthalamic nucleus ^* Parkinson's - substantia nigra pars compacta neuronal cell death ( small clonic => moderate clonic => large clonic Q66=How can epileptic syndromes be classified? A66=* Localization-related epilepsies ^o Aka partial epilepsies ^o Idiopathic partial epilepsies (genetic) ^* Benign rolandic epilepsy ^* Benign childhood epilepsy with occipital paroysms ^* Familial temporal lobe epilepsy ^* Autosomal dominant nocturnal frontal lobe epilepsy ^o Symptomatic/cryptogenic partial epilepsy ^* Temporal lobe epilepsy ^* Frontal lobe epilepsy ^* Parietal lobe epilepsy ^* Occipital lobe epilepsy ^* Generalized epilepsies ^o Idiopathic ^* Childhood absence epilepsy ^* Juvenile absence epilepsy ^* Juvenile myoclonic epilepsy ^* Epilepsy with grand mal seizures on awakening ^* Benign neonatal familial convulsions ^* Benign myoclonic epilepsy in infancy ^* Epilepsy with seizures precipitated by specific modes of activation - reading epilepsy ^o Symptomatic/cryptogenic ^* Infantile spasms ^* Lennox Gastaut syndrome ^* Epilepsy with myoclonic absences ^* Epilepsy with myoclonic astatic seizures ^* Undetermined epilepsies ^o Landau-Kleffner syndrome ^o Epilepsy with continuous spike waves during slow wave sleep ^o Severe myoclonic epilepsy in infancy Q67=When should treatment be initiated for seizures? A67=* With single unprovoked seizure, do not treat, because most will not recur ^* Remote symptomatic causes have a higher recurrence risk, but may also just be observed if MRI and EEG are normal ^* Patients with a remote cause and a history of acute symptomatic seizures should be treated, because they have a 100% recurrence rate ^* Because there is a 20% chance that patients will be refractory to medical treatment, those patients should be considered for surgery Q68=What are the appropriate anti-epileptic drugs for different types of seizures/epilepsies? A68=* Partial epilepsy - male = phenytoin (hirsutism); female or adolescent = carbamazepine ^* Avoid valproate in pregnant women and individuals with family history of spina bifida ^* Primary generalized (idiopathic) - valproate ^* Partial seizures and generalized tonic-clonic - topiramate is an add-on ^* Partial seizures - neurontin is an add-on Q69=What is convulsive status epilepticus and how is it treated? A69=* Status epilepticus - 1) continuous seizure lasting >30 minutes; or 2) two or more sequential seizures within 30 minutes ^* Treat acutely with lorazepam (rapid onset, but short half-life) first and then phenytoin (slow onset, long half-life) in saline (not D5W, because precipitates) ^* Fosphenytoin is a good replacement for phenytoin because it is less alkaline Q70=What is the general basis for choosing a particular anticonvulsant for initiating epilepsy therapy? A70=* Selection based mainly on seizure type, not cause Q71=What generally is the main difference between a first-line and second-choice anticonvulsant when either drug would be suitable for the patient, but one is generally preferred to start treatment? A71=* A drug is generally first line because of better relative safety, not necessarily greater efficacy Q72=What is the general value of, or needs for, monitoring anticonvulsant drug serum levels? A72=* Checking serum levels allows monitoring for noncompliance (no drug in serum, patient isn't taking meds) Q73=In the context of long-term drug treatment of epilepsy, what is the most frequent cause of apparent "lack of efficacy?" A73=* Noncompliance Q74=What brain neurotransmitter seems to be the "target" of anticonvulsant action, in one way or another, depending on the anticonvulsant? A74=* Gamma-aminobutyric acid Q75=What are the normally preferred first and second drug(s) for generalized tonic-clonic seizures, absence seizures, and partial/focal seizures? A75=* Tonic-clonic seizures - 1 = phenytoin; 2 = phenobarbital ^* Absence seizures - 1 = ethosuximide; 2 = valproic acid ^* Partial/focal seizures - 1 = phenytoin; 2 = carbamazepine Q76=What are the most serious toxicities or adverse responses, as well as the more common side effects, of phenytoin, carbamazepine, phenobarbitol, valproic acid, ethosuximide, and clonazepam? A76=* Phenytoin - extensive gingival hyperplasia (UNIQUE); aggrevates absence seizures; CNS (ataxia, vertigo, diplopia, nystagmus); hematologic (folate, vit K def) ^* Carbamazepine - agranulocytosis, aplastic anemia (UNIQUE); dizziness, GI upset; vit K dependent bleeding ^* Phenobarbitol - sedation; vit K dependent bleeding; tolerance is common ^* Valproic acid - GI distress, weight gain (appetite stimulation); hepatotoxicity (IMPORTANT); alopecia (UNIQUE); teratogenic (IMPORTANT); thrombocytopenia ^* Ethosuximide - headache; dizziness; GI distress ^* Clonazepam - sedation; tolerance; seizure exacerbation when drug discontinued Q77=What anticonvulsant(s) is/are important for long-term treatment of "metabolic autoinduction?" A77=* Phenytoin and carbamazepine are autoinducers Q78=Which three anticonvulsants are hepatic inducers and which is a hepatic inhibitor? A78=* Hepatic inducers: phenytoin, carbamazepine, phenobarbitol (barbiturates, OCP's, rifampin, warfarin, theophyline) ^* Hepatic inhibitor: valproic acid (cimetidine) Q79=What is the most common mechanism of interactions between common anticonvulsants (e.g. phenytoin and barbiturates, primidone, valproic acid, carbamazepine)? A79=* Hepatic induction Q80=What is currently the "most often recommended" pharmacologic approach to managing status epilepticus? A80=* Initially IV benzodiazepine (e.g. lorazepam (ATIVAN)) ^* Follow-up with IV phenytoin (DILANTIN) Q81=What are the benefits and limitations of using IV benzodiazepine or phenytoin alone for treating status epilepticus? A81=* Benzodiazepine - fast-acting, so effects gone quickly, allowing recurrence ^* Phenytoin - enters brain slowly, so delayed onset; very alkaline, so irritating to veins (overcome with newer fos-phenytoin) Q82=What precautions must be taken, for both the mother and newborn, when phenytoin or phenobarbital is administered to pregnant women? A82=* Vitamin K and folate supplementation Q83=What region of the body is the main source of behavior? A83=* Brain Q84=How was the fact that the brain is the source of behavior first determined and what techniques have been used to establish brain-behavior linkages? A84=* First established with naturally-occurring lesions (e.g. war injuries) ^* Other - surgical lesions; electrical stimulation studies; neuropsychological test batteries; biochemical measures (e.g. CSF); neuroendocrine challenge tests; psychophysiological measures (e.g. EEG); brain imaging (e.g. CT, MRI, PET); genetic studies (e.g. gene expression or knock-outs) Q85=What are behavior and how does abnormal behavior develop? A85=* Normal - the "final common manifestation" of perceptions, cognitive processes, affective regulation, and behavioral outputs. ^* Abnormal - dysregulation of any of the aspects of normal behavior. Q86=How are the various behavioral functions (e.g. perception, cognition, affect/mood, and behavior) mediated and regulated in the brain? A86=* Mediated - various types of message transmission (e.g. electrical and neurochemical) ^* Regulated - genetic influences on neurotransmitter storage and release Q87=What is the limbic system, its important components, and the normal behaviors regulated by its components? A87=* Limbic system - collection of nuclei and tracts that are intimately related to behavioral expression in animals and man ^* Components - amygdala, hippocampus, medial forebrain bundle, septal regions, hypothalamus, and anterior cingulate cortex ^* Behaviors - pain/pleasure; reward/reinforcement; aggression; fear; appetite/satiety; taste; autonomic regulation; chronobiological rhythm; sleep; libido; short-term memory/learning; concentration; psychomotor regulation; prosody; separation/bereavement; maternal behavior Q88=Are limbic networks stable or plastic and why is this important? A88=* As with other parts of the brain, the limbic networks are plastic and consequently constantly influenced and modified by developmental, psychological, and social experiences. Q89=Why is the "mind-body" dichotomy outdated and unscientific? A89=* Because the brain is plastic and... | |
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