What Causes Lightheadedness And Altered Sense Of Smell?
A focal seizure is probable.
Detailed Answer:
I read your question carefully and I understand your concern.
That description of those short episodes is compatible with a seizure, not the commonly known convulsive seizure but a focal seizure, related to a discharge limited to a particular area of the brain, in this case most probably the temporal lobe of the brain.
The MRI is the correct most important test in this case, as focal seizures have usually a focal cause, at his age most probable one is a tumor or less likely a small stroke, detectable by the MRI. An EEG is also usually part of the evaluation to check for epileptiform abnormalities along with some routine blood tests he's probably already had, but MRI is really the most important test.
Treatment can involve drug for seizures and according to the MRI findings the need for other measures will be discussed.
I remain at your disposal for further questions.