Skip to content

Quiz: The Neuroscience of Neurodegeneration

Test your understanding of the cellular and molecular mechanisms of dementia with these 10 review questions. Click "Show Answer" to check your work.

1. Which protein forms the sticky plaques found outside neurons in Alzheimer's disease?

  1. Alpha-synuclein
  2. Beta-amyloid
  3. Tau protein
  4. Myelin basic protein
Show Answer

The correct answer is B. Beta-amyloid is a protein fragment that, in Alzheimer's disease, accumulates faster than the brain can clear it. Pieces stick together forming plaques in the spaces between neurons. Alpha-synuclein forms Lewy bodies inside neurons in Lewy body dementia, while tau protein forms tangles inside neurons in Alzheimer's and related conditions.

Concept Tested: Beta-Amyloid

2. Neurofibrillary tangles are abnormal twisted fibers formed from which protein?

  1. Beta-amyloid
  2. Tau protein
  3. Alpha-synuclein
  4. Prion protein
Show Answer

The correct answer is B. Neurofibrillary tangles are twisted fibers of abnormal tau protein that form inside dying neurons. In healthy neurons, tau helps stabilize microtubules that transport nutrients and signaling molecules. When tau becomes hyperphosphorylated, it detaches and clumps into tangles, disrupting the neuron's internal transport system and contributing to cell death.

Concept Tested: Neurofibrillary Tangles

3. What is the primary difference between amyloid plaques and neurofibrillary tangles?

  1. Plaques form inside neurons, while tangles form outside
  2. Plaques form outside neurons, while tangles form inside neurons
  3. Plaques only occur in young people, tangles only in older people
  4. They are actually the same thing with different names
Show Answer

The correct answer is B. Amyloid plaques form in the extracellular spaces between neurons and are made of beta-amyloid. Neurofibrillary tangles form inside neurons and are made of tau protein. Both are hallmarks of Alzheimer's disease, but they occur in different locations and involve different proteins, each contributing to neurodegeneration in distinct ways.

Concept Tested: Amyloid Plaques

4. Alpha-synuclein forms abnormal deposits called Lewy bodies and is most closely associated with which condition?

  1. Vascular dementia
  2. Lewy body dementia and Parkinson's disease
  3. Wernicke-Korsakoff syndrome
  4. Frontotemporal dementia
Show Answer

The correct answer is B. Alpha-synuclein normally helps regulate neurotransmitter release at synapses. When it misfolds and clumps, it forms Lewy bodies inside neurons, which are the defining feature of Lewy body dementia and are also found in Parkinson's disease. This shared pathology is why Parkinson's disease often progresses to include dementia symptoms.

Concept Tested: Alpha-Synuclein

5. The amyloid cascade hypothesis proposes that:

  1. Beta-amyloid accumulation triggers a chain of events leading to tau problems, neuron damage, and dementia
  2. Tau tangles cause beta-amyloid to build up
  3. Dementia starts in the spinal cord and spreads to the brain
  4. Amyloid plaques are harmless byproducts of normal aging
Show Answer

The correct answer is A. The amyloid cascade hypothesis is the leading theory of Alzheimer's disease. It proposes that beta-amyloid accumulation is the initial trigger that causes inflammation, tau abnormalities, synaptic dysfunction, and ultimately neuron death. While debated, this model guides most drug development efforts, including medications that target amyloid directly.

Concept Tested: Beta-Amyloid

6. Pick's disease is a rare form of dementia associated with which of the following?

  1. Progressive loss of movement coordination only
  2. Abnormal tau deposits primarily damaging the frontal and temporal lobes
  3. Genetic mutations affecting the occipital lobe
  4. A sudden onset of memory loss due to stroke
Show Answer

The correct answer is B. Pick's disease is a rare form of frontotemporal dementia characterized by abnormal tau deposits called Pick bodies. It primarily damages the frontal and temporal lobes, leading to changes in personality, behavior, and language rather than memory loss. It is one of several tauopathies related to FTD.

Concept Tested: Pick's Disease

7. Progressive supranuclear palsy (PSP) is a rare neurodegenerative disease that typically causes:

  1. Only memory problems without movement issues
  2. Balance problems, difficulty with eye movements, and cognitive decline
  3. Hearing loss followed by language loss
  4. A sudden onset of visual hallucinations
Show Answer

The correct answer is B. Progressive supranuclear palsy is a tauopathy that causes balance problems (leading to falls), characteristic difficulty moving the eyes especially in the vertical direction, stiffness, and cognitive decline. It is often mistaken for Parkinson's disease early on, but the eye movement problems and lack of response to Parkinson's medications help distinguish it.

Concept Tested: Progressive Supranuclear Palsy

8. A caregiver asks how plaques can be present in the brain for 15-20 years before dementia symptoms appear. What is the best explanation?

  1. The plaques are dormant until triggered by stress
  2. Cognitive reserve and compensating neural pathways can mask damage until a threshold is crossed
  3. Plaques do not actually cause symptoms on their own
  4. Symptoms appear instantly when the first plaque forms
Show Answer

The correct answer is B. Amyloid plaques often begin forming 15-20 years before symptoms appear. During this long preclinical period, the brain compensates through cognitive reserve, neuroplasticity, and alternative neural pathways. Once damage exceeds the brain's ability to compensate, symptoms emerge. This long window represents an important opportunity for early intervention and prevention research.

Concept Tested: Amyloid Plaques

9. Which of the following best describes how tau protein functions in a healthy neuron?

  1. It forms the outer wall of the cell
  2. It stabilizes microtubules that transport molecules through the neuron
  3. It stores memories
  4. It produces neurotransmitters
Show Answer

The correct answer is B. In healthy neurons, tau protein stabilizes microtubules, the internal highways that transport nutrients, proteins, and signaling molecules throughout the cell. When tau becomes hyperphosphorylated in Alzheimer's disease, it detaches from microtubules and clumps into tangles, collapsing the transport system and leading to cell dysfunction and death.

Concept Tested: Tau Protein

10. Corticobasal degeneration is distinguished by which combination of features?

  1. Memory loss and visual hallucinations only
  2. Asymmetric movement problems (one side of body affected more than the other) combined with cognitive changes
  3. Sudden cognitive loss following a stroke
  4. Pure language loss without any motor symptoms
Show Answer

The correct answer is B. Corticobasal degeneration is a rare tauopathy that classically causes asymmetric symptoms, meaning one side of the body is affected more than the other. Patients may experience stiffness, jerky movements, apraxia (inability to perform learned movements), and cognitive changes. The asymmetric presentation helps distinguish it from other parkinsonian disorders.

Concept Tested: Corticobasal Degeneration