MRI Scan of My Head

Yesterday at 8 am I went to the HealthCare Global (HCG) Hospital, Bangalore to do an MRI (Magnetic Resonance Imaging) scan of my head.

Well, there is nothing wrong with me; I was just volunteering for a research project on Alzheimer's Disease conducted by Center for Neuroscience, IISc, Bangalore. 

See more details here: How Our Mind Gets Things Right!

First Ms. Santhoshi, Psychologist took me through an MRI Screening checklist. Then I was taken into the MRI room and asked to lie down on a comfortable, padded table. Ms. Ranjini, the lead Psychologist, told me to lie down still and cautioned me not to concentrate on anything and also not go to sleep. She made sure that I was comfortable with the earplugs, earphone, the emergency switch, and the blanket. Then the table was advanced into the MRI gantry so that my head is positioned properly to perform the scan.

The MRI machine uses two powerful magnets and a computer to create detailed cross-sectional images of the head's internal parts. An MRI scan is a non-invasive and painless procedure.

Our body is largely made of water molecules comprised of hydrogen and oxygen atoms. The proton at the center of each atom serves as a magnet that is sensitive to a magnetic field. Normally the water molecules are randomly arranged. The first magnet of the MRI scanner causes the atoms to align in a north-south direction. The second magnet is turned on and off in a series of quick pulses. When it is turned on, each hydrogen atom changes its alignment and then quickly goes back to its original state when switched off. The scanner detects these changes and, with the computer, creates the cross-sectional images.

Functional MRI (fMRI) uses MRI technology to measure brain activity by detecting the changes in blood oxygenation and blood flow in the brain. This brain mapping gives researchers an insight into the activity of neurons in the brain as blood flow increases in areas where neurons are active.

When the scan was started I could hear the knocking or thumping noise caused by magnets being turned on and off. This rhythmic sound really makes you sleepy any my biggest challenge was to stay awake during the whole procedure. The scanning continued for 90 minutes with small breaks for relaxation. In one of the sessions, the computerized cognitive assessment test, which I had taken earlier, was repeated.

My wife Vasantha Unnikrishnan, who is also a volunteer, preferred not to undergo the MRI scan as she felt that the frequent headaches that she used to have earlier may recur as a result of the head scan.