Demyelination & Synaptic Function

Which of the following best describes the underlying mechanism of Guillain-Barré Syndrome that leads to demyelination?

In the context of synaptic transmission, what would be the most immediate consequence of blocking voltage-gated calcium channels on the presynaptic neuron?

Progressive multifocal leukoencephalopathy (PML) is a demyelinating disease caused by the reactivation of the JC virus. What condition creates an environment that allows for this reactivation?

In a patient presenting with ascending muscle weakness, loss of reflexes, and a history of a recent infection, which pathological mechanism is most likely contributing to these symptoms?

A patient with poorly controlled diabetes mellitus is likely to develop diabetic neuropathy and retinopathy. Which of the following mechanisms is the primary cause of these complications?

In the indirect pathway of the striatum, what is the effect of decreased GABA release from the globus pallidus externa (GPe) onto the subthalamic nucleus?

How does dopamine binding to D2 receptors in the striatum affect the activity of the globus pallidus externa (GPe)?

What is the primary role of the basal ganglia in motor function?

A patient presents with increased motor coordination and fluidity of movement. Based on the indirect pathway of the striatum, which of the following scenarios is most likely occurring in their basal ganglia?

What is the expected motor outcome when the subthalamic nuclei are highly stimulated and releasing large amounts of glutamate onto the globus pallidus interna (GPi)?

In the context of the basal ganglia, how does the disruption of dopamine signaling (as seen in Parkinson's disease) primarily manifest in terms of motor control?

If the striatum is unable to release GABA onto the GPe, what is the resulting effect on the subthalamic nuclei?

Damage to the substantia nigra pars compacta, which reduces dopamine production, would have what effect on the GPi, according to the indirect pathway?

In the direct pathway of the striatum, what is the consequence of dopamine binding to D1 receptors?

Which of the following describes the effect of decreased dopamine release in the direct pathway of the striatum?

Which specific area of the substantia nigra experiences the most significant impact from Parkinson's Disease, leading to a reduction in dopamine release?

What motor symptom is most indicative of advanced Parkinson's Disease?

Why is carbidopa administered in conjunction with levodopa in the management of Parkinson's Disease?

How do MAO-B inhibitors work to alleviate symptoms of Parkinson's Disease?

Why is bromocriptine, an ergot-based dopaminergic agonist, not typically the first-line treatment for Parkinson's Disease?

What is the enzymatic role of Dopa Decarboxylase in the context of Parkinson's Disease treatment?

A patient in the intensive care unit exhibits repetitive focal motor activity in their right arm, with preserved awareness. EEG confirms localized epileptiform discharges in the contralateral motor cortex. Which of the following is the MOST appropriate initial classification?

A patient is brought to the emergency department in status epilepticus. After initial stabilization with IV benzodiazepines, which of the following medications would be MOST appropriate to administer next for long-term seizure control?

A patient with a history of COPD presents with altered mental status and new-onset seizures. Lumbar puncture reveals evidence of bacterial meningitis. Which of the following is the MOST likely causative organism?

Which of the following mechanisms BEST explains how hyponatremia contributes to the development of seizures?

A 22-year-old college student presents with fever, headache, and nuchal rigidity followed by a generalized tonic-clonic seizure. Which of the following is the MOST likely cause of their condition?

A patient with a history of HIV/AIDS presents with gradual onset of altered mental status and seizures. An MRI of the brain reveals multiple non-enhancing white matter lesions. Which of the following is the MOST likely infectious etiology?

Which of the following mechanisms BEST explains how hemorrhagic stroke increases the risk of seizures compared to ischemic stroke?

A patient returning from a hiking trip presents with a rash, joint pain, and new-onset seizures. Which of the following infectious etiologies is MOST likely?

In Huntington's disease, the expansion of CAG trinucleotide repeats leads to an accumulation of Huntingtin protein. What specific effect does this accumulation have on neuronal function within the basal ganglia?

Why does the degeneration of the striatum in the early stages of Huntington's disease lead to hyperkinetic movements such as chorea and athetosis?

In the later stages of Huntington's disease, patients often develop bradykinesia and rigidity, similar to Parkinson's disease. What is the primary pathological change that accounts for this transition?

How do the visuospatial deficits seen in Huntington's disease manifest, and what specific neural pathway is implicated in these deficits?

What is the primary mechanism by which the accumulation of Huntingtin protein leads to the characteristic enlargement of the lateral ventricles observed in neuroimaging of Huntington's disease patients?

Why do disruptions of striatal neurons projecting to the frontal cortex in Huntington's disease result in a lack of behavioral and social inhibitions?

How does the destruction of the striatum affect the release of GABA (gamma-aminobutyric acid) in the basal ganglia circuit during the early stages of Huntington's disease, and what is the consequence of this change?

What distinguishes the hyperkinetic movement disorder seen in early Huntington's disease in contrast to the hypokinetic movement disorder observed with Parkinson's Disease?

Which of the following physiological changes is the MOST likely direct consequence of the decreased GABA transmission observed during acute benzodiazepine cessation in a chronically dependent patient?

A patient with a history of chronic benzodiazepine abuse presents with anxiety, tremors, and heart palpitations 12 hours after their last dose. Which benzodiazepine withdrawal characteristic should the physician consider FIRST when determining the appropriate course of treatment?

A patient undergoing alcohol withdrawal develops severe agitation, visual hallucinations, and life-threatening autonomic instability. Which condition is MOST likely indicated by this presentation?

Which of the following is the MOST appropriate initial treatment strategy for a patient experiencing severe agitation and aggression during acute alcohol withdrawal?

A patient with chronic alcohol use presents with severe nausea and abdominal pain during alcohol withdrawal. What underlying condition should be considered as a PRIMARY contributor to these symptoms?

A patient in acute benzodiazepine withdrawal is exhibiting paranoia that is escalating into frank aggression. Apart from pharmacological interventions, which immediate step is MOST crucial for ensuring patient and staff safety?

A patient with a history of chronic alcohol abuse is admitted for detoxification. On the third day, the patient develops visual and tactile hallucinations, severe agitation, and significant autonomic instability. After administering appropriate pharmacological interventions, which of the following should be the NEXT priority in managing this patient?

During which timeframe after the last alcoholic beverage is a patient MOST likely to experience Delirium Tremens?

Saltatory Conduction

PML

Parts of a Synapse

Role of Calcium

Guillain-Barre Syndrome

Direct Pathway of Striatum

Role of Dopamine in Striatum

GPi Function

Effects of Decreased Dopamine

Symptoms of Parkinson's Disease

Levodopa + Carbidopa

Dopaminergic Agonists

MAO-B Inhibitors

Generalized Convulsive Status Epilepticus

Non-Convulsive Status Epilepticus

Focal Status Epilepticus

Management of Status Epilepticus

Infectious Causes of Seizure

Hyponatremia and Seizures

Streptococcus Pneumoniae

Herpes Viruses in Encephalitis

Basal Ganglia

Parts of Basal Ganglia

Motor Cortex

Role of Dopamine

GABA

Glutamate

Parkinson's Disease

Benzodiazepine Withdrawal Symptoms

Short-acting Benzodiazepines

Long-acting Benzodiazepines

Early Symptoms of Withdrawal

Late Symptoms of Withdrawal

Delirium Tremens (DT)

Management of Benzodiazepine Withdrawal

Alcohol Withdrawal Seizures

CAG Trinucleotide Repeats

Striatum

Enlargement of Lateral Ventricles

Hyperkinetic Phenotypes

Chorea

Bradykinesia

Neuropsychiatric Deficits

Dopamine Release