Question

Describe some hypothesis regarding brain function you can test with fMRI. How would you set up an experiment to test this hypothesis. What would the subject do in the MRI machine?

Answer 1

fMRI stands for functional magnetic resonance imaging. It is a method used to study the active brain areas as the subject performs a certain task.

Different areas of the brain are involved in doing specific tasks. We can look at the easy to access area of the visual cortex. This area is located in the occipital region. We know that the retina of the eye detects the photons. They have two kinds of photoreceptors namely, rods and cones. Rods are specialized for dim vision while cones are specialized for color vision. Since both of these capture information from the external world in a different way, they should be projected to different layers in the visual cortex before being integrated.

Hence our hypothesis could be that bright and dim vision would be recognized in different visual cortical layers.

To check for this, we can train the subjects on the task to visualize on a computer screen certain bright images. This can then be followed by a dark screen dim images. The same can be performed in an fMRI machine and the recordings can be obtained from the visual cortical layers.