Lesson 3.2.3.4.2

3.2.3.4.2 Scanning techniques: CT, PET and fMRI Quiz: AQA Psychology, Unit 7

20 questions

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Lesson 3.2.3.4.2, Scanning techniques: CT, PET and fMRI: 20 multiple choice questions for the AQA GCSE Psychology (8182), Unit 7: Brain and neuropsychology, written with Revision Ninja.

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The 20 questions

  1. Which scan builds a detailed structural image of the brain from X-rays taken at many angles?

    • CT scan, which combines many X-ray images into a structural picture
    • fMRI scan, which tracks changes in blood oxygen during a task
    • EEG recording, which measures electrical signals from electrodes on the scalp
    • PET scan, which tracks the chemical activity of brain tissue over time

  2. Which scan injects a radioactive tracer that collects in active brain tissue so activity can be seen?

    • fMRI scan, which uses magnetic fields to show changes in blood oxygen
    • Structural MRI scan, which uses magnetic fields to show the brain's anatomy
    • CT scan, which uses X-rays to show the structure of brain tissue
    • PET scan, which uses a radioactive tracer to show where activity is high

  3. What does an fMRI scan detect to show which brain regions are active?

    • Changes in blood oxygen levels in regions that are working harder
    • Electrical discharges recorded through electrodes placed on the scalp
    • X-ray absorption by dense bone and brain tissue across the skull
    • Radioactive decay of a tracer that has collected in the bloodstream

  4. Why can an fMRI scan usually be repeated more safely than a PET scan?

    • It records electrical signals from deep inside the brain each session
    • It needs a larger radioactive dose of tracer to work each time
    • It avoids ionising radiation and radioactive tracers altogether
    • It produces much sharper images of the bone structure of the skull

  5. After a head injury, which scan would best show the detailed physical structure of the brain?

    • PET scan, which mainly shows the chemical activity levels in brain tissue
    • CT scan, which gives a detailed image of the brain's structure
    • fMRI scan, which mainly tracks changes in blood flow during a task
    • EEG recording, which records only the electrical activity of the brain

  6. A PET image shows strong colour in one region. What does this most likely indicate?

    • That region has a thicker bone layer than the surrounding skull
    • That region took up more tracer, so it is more metabolically active
    • That region was exposed to the strongest magnetic field in the scanner
    • That region has lost most of its neurons through a recent injury

  7. Which statement about CT scans is correct?

    • They record electrical activity using electrodes placed on the scalp
    • They track changes in blood oxygen levels during a memory task
    • They rely on a radioactive tracer to show brain activity over time
    • They use X-rays to build structural images of the brain

  8. Which scan would best show changes in brain activity while a person completes a memory task?

    • EEG cap, which records only the shape and thickness of the skull
    • Skull X-ray, which shows the bone of the skull rather than brain tissue
    • CT scan, which takes a single structural snapshot of the brain at rest
    • fMRI scan, which tracks blood oxygen changes during the task itself

  9. A scan shows a brain area lighting up when a participant reads aloud. Which technique most likely produced this?

    • CT, because it shows the density of brain tissue in a single slice
    • Skull X-ray, because it shows the thickness of the bone around the brain
    • fMRI, because it detects increased blood oxygen in areas that are active
    • Electrode cap, because it records the shape of the skull during reading

  10. Which of these is a limitation of PET scanning?

    • It requires the participant to lie still inside a strong magnetic field
    • It produces only black and white images of the bone in the skull
    • It cannot show any difference in brain activity between two tasks
    • It exposes the participant to radiation from a tracer

  11. A patient has a CT scan showing a small lesion. Which additional scan would help show whether that area affects brain activity?

    • An ultrasound of the neck, which shows the position of the spinal column
    • fMRI scan, which can show changes in activity in the lesion region
    • A skull X-ray, which shows only the thickness of the bone around it
    • A second CT scan, which would show the same structural image again

  12. Which scanning technique uses magnetic fields and radio waves to produce images?

    • fMRI scan, which uses magnetic fields and radio waves
    • Skull X-ray, which uses a single beam of X-rays through the skull
    • PET scan, which detects radiation from a tracer in the brain
    • CT scan, which uses a rotating beam of X-rays through the head

  13. Which feature do CT, PET and fMRI all share?

    • They all use X-rays to create the images of brain tissue
    • They are all used to produce images of the living brain
    • They all require a radioactive tracer to be injected first
    • They all record electrical activity through electrodes on the scalp

  14. A researcher says fMRI shows brain structure more clearly than CT. Which response is most accurate?

    • Incorrect, because CT is generally better at showing structure while fMRI shows activity
    • Correct, because fMRI tracks the decay of a radioactive tracer to reveal the brain's fine structure
    • Correct, because fMRI uses X-rays to build a more detailed structural image than CT scans
    • Incorrect, because fMRI is only useful for measuring electrical signals rather than brain images

  15. Which scan could show that a brain area is more active when a participant is anxious?

    • CT, because it measures the bone density around the anxious area
    • PET, because the tracer collects more in areas with higher activity
    • Skull X-ray, because it shows the shape of the brain inside the skull
    • EEG cap, because it displays the physical structure of the skull

  16. A PET study uses a tracer that becomes radioactive as it collects in tissue. Why should researchers limit the number of scans a participant has?

    • Each scan uses up the tracer, so later scans would show no activity at all
    • Each scan weakens the magnetic field, which blurs the images of the brain
    • Each scan changes the blood oxygen level, so later results cannot be compared
    • Each scan adds radiation exposure, so the participant's total dose must be controlled

  17. Why might a researcher use both CT and fMRI in one study?

    • To make both scans cheaper for the participant to complete overall
    • To link a structural image of the brain with a measure of activity in the same area
    • To remove the need for any tracer or contrast agent in the procedure
    • To measure blood sugar and bone density at the same time in one visit

  18. A scanner detects blood oxygen changes in the visual cortex while a participant views an image. Which technique is this?

    • CT, since it detects changes in X-ray absorption across brain tissue
    • fMRI, since it detects changes in blood oxygen linked to brain activity
    • EEG, since it detects electrical signals recorded from the scalp surface
    • PET, since it detects the decay of a radioactive tracer in the blood

  19. Which scan is most suitable for tracking how activity in one brain area changes over a short task that is repeated several times?

    • fMRI, which can be repeated frequently without ionising radiation
    • PET, which needs a fresh radioactive tracer injection for every single short scan
    • Skull X-ray, which takes many images of the bone over the course of a task
    • CT, which produces only one structural image of the brain in each session

  20. Which claim about scanning techniques is most accurate?

    • CT and PET both rely on magnetic fields to produce detailed brain images
    • fMRI is always the best choice because it shows both structure and tracer uptake
    • Different scans answer different questions, such as structure from CT and activity from PET or fMRI
    • PET and fMRI both show the physical structure of bone more clearly than CT

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