MRI Functional Imaging of the Brain (fMRI)

What is it?

A magnetic resonance functional imaging (fMRI) of the brain is a noninvasive procedure using no radiation and measures brain activity by observing changes in blood oxygenation and flow in response to neural stimulation. It can create dozens or sometimes hundreds of images in a short time.

What is it for?

An MRI functional imaging of the brain is used to examine the brain and evaluate which parts of the brain are managing critical activities. It can also analyze stroke effects and help in determining brain treatment. This imaging procedure can often detect complex brain problems that other diagnostic tests cannot. It is also used in observing brain tumors.

How to prepare

  • You will be given special instructions about what to eat and drink prior to the exam
  • Talk to your health care provider about your medical history, current medical condition, medicines you are taking and any allergies you have
  • You will be asked if you have any implanted medical devices. Implanted medical devices can malfunction or cause problems during an MRI.


  • An allergic reaction may occur from the use of a contrast material (dye)
  • The strong magnetic fields can cause pacemakers and other implants to malfunction
  • Metal inside your body may be moved or shifted slightly because of the magnetic fields
  • An MRI is not recommended if you are pregnant, as it can cause a harmful increase in the temperature of the amniotic fluid

What happens during?

  • You may be given a sedative to help you relax and feel comfortable and less anxious
  • You will be positioned on a moveable examination table. Straps, braces and fasteners may be used to keep you still during the procedure. It’s important to keep still to ensure that precise images are taken.
  • Contrast material may be used. It is injected in your hand or arm by I.V. The contrast material helps to clearly see specific areas.
  • You will be in a separate room from the MRI technologist but you will be watched and in constant communication with the technologist.
  • The scan takes between 30 to 60 minutes but may go longer

What happens after?

  • There is no recovery time unless you were given a sedative to relax
  • You can resume your regular diet and activities following the MRI

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