Brain MRI is a relatively new technology that allows scientists to “read” a person’s thoughts on a computer screen. The Magnetic Resonance Imaging has applications in several scientific specialties. Our focus on this page is in neuroscience where MRI is used for a brain scan. The method is officially called functional Magnetic Resonance Imaging or fMRI.
Recently I was reading a magazine, and it had an article about fMRI and how scientists can read our minds. I found it fascinating and I did some basic research on the field that I will present you briefly on this page.
What is an MRI brain scan?
fMRI technology allows scientists to observe whatever happens in our brain:
o The Images we see
o The words we read
o The sounds we listen to
o The routes we follow
o Our intentions
o Our Unconscious activity
o Our thoughts in general
Many ethical questions arise upon such a discovery. Up to now, our thoughts are the only private space we have and no one could gain access to them. There is an imperative need for a law establishment for the usage of these technologies.
How does a brain MRI work?
While we hear a sound, the brain cells (neurons) in the auditory area of the brain cortex, needs more blood and consumes more oxygen. An fMRI causes a reaction of the molecules of a blood protein that is responsible for oxygen carrying, and detects these molecules.
For the visualization of this data in a computer monitor, the computer divides the brain into small volume elements that are called voxels. These voxels equal approximately to 50 mm3. Every voxel contains 5 million neurons that are interconnected through 50 km of dendrites and 200 km of axons. All these connect to 30 billion points (synapses). Impressive…
The fMRI detects only the oxygen exchange that happens in every voxel. Then it represents with yellow and red color gradations the active voxels and with green color the inactive ones. In simple words, an fMRI observes and measures the oxygen consumption in the brain areas.
And what about brain MRI accuracy?
Let’s see some interesting experiments of brain MRI scans.
In 2002, Dr. Daniel Langleben wanted to check the brain activity when someone cheats in a card game. He gave two cards in two students and instructed them to memorize the cards without telling him which card they were given. Then he asked the students to lie for one card and to tell the truth for the other card. He was performing brain MRI to the students and every 3 seconds, a monitor showed them a random card.
From their brain reactions, as accurately recorded from the MRI scan, Langleben confirmed that he could identify which cards the students were given and also for which cards they lied about at an impressive accuracy rate of 96%.
Another remarkable experiment took place in 2008 at California University by Jack Gallant. While being in fMRI scan, a person sees many pictures. In the meantime, the scanner analyzes the resulting brain activity curve. A computer analyzes the images according to the “way we see” and searches for correlations in the brain activity curve. A pattern for each picture results from this procedure.
In the last phase of the experiment, the researchers show to the person 120 more pictures, while they compare the brain activity curve of each image, until the pattern detects which picture is the one that the person sees. The success rate ranges from 72% up to 92% in two people.
If the letters can be assumed as pictures then with the brain MRI, we can read the words that someone sees. In a similar way, we can scan and detect sounds, emotions, and nearly every thought. Functional Magnetic Resonance Imaging is a technology that can reveal us many uncovered mysteries of the human brain and mind, but we have to use it wisely and not for spying purposes.