Whole Brain Imaging -Test 1 Flashcards
In a study investigating the neural correlates of memory formation, researchers decide to employ a whole brain imaging technique to visualize changes and brain activity during memory tasks. Which imaging modality would be most suitable for capturing detailed spatial information about brain activation patterns associated with memory processes?
Functional magnetic resonance imaging (fMRI)
Which of the following statements accurately distinguishes between Alzheimer’s disease and Parkinson’s disease?
Alzheimer’s disease associated with a decline in cognitive functions, whereas Parkinson’s disease is characterized by tremors and movement difficulties
In the progression of Alzheimer’s disease, which of the following represents the typical sequence of stages?
Mild cognitive impairment (MCI), early stage Alzheimer’s, moderate dementia, severe dementia
What is the primary purpose of the mini-mental state examination (MMSE)?
To evaluate cognitive function and screen for dementia
Aducanumab, a medication that gained attention in the treatment of Alzheimer’s disease, is designed to target:
Amyloid-beta plaques
Which of the following pathological features is commonly associated with Alzheimer’s?
Neurofibrillary tangles
What is the primary purpose of a meta-analysis in scientific research?
To combine and analyze results from multiple studies on a specific topic
What is the main structural difference between amyloid plaques and neurofibrillary tangles in the context of Alzheimer’s disease?
Amyloid plaques are extracellular deposits of beta-amyloid, while neurofibrillary tangles are intracellular aggregates of tau protein
In amyloid PET imaging, which brain region is often used as a negative control or reference region?
Cerebellum
Why is histology often used as a “standard of truth” in amyloid PET assessments?
To validate the accuracy of PET imaging by directly examining brain tissue
What is a positron?
An anti-particle with the same mass as an electron but a positive charge
Which of the following statements accurately describes the isotopes of hydrogen?
Protium, deuterium, and tritium are three isotopes of hydrogen
When a positron annihilates with an electron, what is the result of this process?
Formation of gamma rays (photons).
In a cyclotron, oxygen-18 can be used to produce a positron-emitting isotope for positron emission tomography (PET). What is the resulting isotope produced through the bombardment of oxygen-18?
Fluorine-18
In PET (positron emission tomography) imaging for research, what is typically used as a radiotracer to visualize brain metabolism?
FDG (Fluorodeoxyglucose)
What is the approximate half-life of Fluorine-18 (F-18), a commonly used radionuclide in PET tracers?
110 minutes
What is a common limitation of PET (positron emission topography) imaging?
Limited spatial resolution
Which of the following statements accurately describes the differences between H+ (proton), H (hydrogen atom), and H2 (molecular hydrogen)?
H+ is a proton, H is a hydrogen atom, and H2 is a neutral hydrogen molecule
Why is PET (positron emission tomography) often combined with MRI or CT scanning in hybrid imaging systems?
To enhance the spatial resolution of PET images
In a research study aiming to assess Alzheimer’s disease using PET imaging, what is a crucial consideration in determining the research methodology?
The selection criteria for participants, including demographics and clinical characteristics
Fluorine-18 (F-18) undergoes radioactive decay in PET imaging. What type of decay does F-18 primarily exhibit?
Beta-plus (B+) decay
What is a key distinction between fMRI (functional magnetic resonance imaging) and PET (positron emission tomography) imaging techniques?
fMRI measures changes in blood flow, while PET measures radioactive emissions
What is the typical spatial resolution of MRI in the millimeter (mm) scale?
1 to 2 mm resolution
What is the primary source of contrast in MRI images when specific contrasting agents are not used?
Tissue density variations, mainly in the density of water
What is the primary function of hemoglobin in the human body?
Transportation of oxygen from lungs to tissues
What is a key difference between hemoglobin and myoglobin?
Hemoglobin contains iron and is involved in oxygen transport in blood, while myoglobin is found in muscle cells and aids in oxygen storage
Sickle cell disease characterized by a mutation in the:
Hemoglobin gene
In a research study comparing brain fMRI (functional magnetic resonance imaging) between individuals with sickle cell anemia and normal individuals, what hypothesis could be proposed regarding potential differences, and why?
Brain fMRI patterns in individuals with sickle cell anemia may differ from normal individuals, as the disease could impact cerebral blood flow and oxygenation
How many polypeptide chains make up a functional hemoglobin protein molecule?
Four
What is the role of heme in hemoglobin?
It binds with oxygen to facilitate oxygen transport
What defines the diamagnetic and paramagnetic properties of hemoglobin?
The presence of iron in the heme group
What distinguishes diamagnetic (not magnetic) and paramagnetic (magnetic) properties of ferrous atoms?
Diamagnetic atoms have no unpaired electrons, while paramagnetic atoms have unpaired electrons
Why do oxygenated and deoxygenated hemoglobin generate distinct fMRI signals?
Oxygenated hemoglobin is diamagnetic, while deoxygenated hemoglobin is paramagnetic
What are patients typically asked to do during imaging in fMRI (functional magnetic resonance imaging)?
Engage in specific cognitive tasks or activities
What is a common clinical application of fMRI (functional magnetic resonance imaging)?
Evaluating brain function and mapping neural activity
In Alzheimer’s research utilizing fMRI, which research question aims to explore the functional connectivity changes associated with the progression of the disease?
How do alterations in functional connectivity correlate with cognitive decline in Alzheimer’s disease?
How is fMRI (functional magnetic resonance imaging) utilized in neurosurgery?
To guide surgeons by mapping brain function and identifying critical areas
What ethical concerns arise regarding the use of fMRI for lie detection in court rooms, particularly related to concerns about accuracy and reliability?
The potential impact of inaccurate or unreliable results on legal outcomes
Can fMRI (functional magnetic resonance imaging) be effectively used to detect peripheral neurodegeneration?
No, fMRI is primarily used for central nervous system imaging and is not suitable for peripheral neurodegeneration
Can FDG (Fluorodeoxyglucose) be used in fMRI for functional brain imaging?
No, FDG is not suitable for functional brain imaging using fMRI
What property of hydrogen atoms is particularly useful in MRI?
Magnetic spin
In MRI (magnetic resonance imaging), what does precession refer to?
The rotation of magnetic moments of protons
How can the precession of protons be influenced in MRI to generate signals?
By changing the characteristics of radiofrequency pulses
What is a key difference in composition between white matter and gray matter in the brain?
Gray matter consists primarily of cell bodies, while white matter consists, mainly of myelinated axons
In a saggital section of the human brain:
White matter is primarily located in the center, surrounded by gray matter
In the spinal cord:
White matter is primarily found externally, surrounding gray matter
Why does white matter appear lighter in MRI compared to gray matter?
White matter has lower water content
Where is the corpus callosum located in the human brain?
Between the cerebral hemispheres
Why does cerebrospinal fluid (CSF) appear dark in MRI images compared to brain tissues?
CSF has higher water content
Why is MRI considered less harmful compared to PET (positron emission tomography)?
PET uses ionizing radiation, while MRI does not
