This may attenuate neuronal transmission within central olfactory areas
and could explain the low BSIT values observed in patients with type 2 SD at 3 months.
In 1878, Broca pointed out that a general feature of a mammalian brain was a horseshoe-shaped rim of cortex surrounding the junction between the diencephalon and each cerebral hemisphere, which at the base of the brain ends of this arc, are joined by olfactory areas
so that a complete loop is formed with the olfactory tract and bulb extending anteriorly.
We, therefore, aimed to investigate modifications of functional connectivity caused by olfactory training in the left and right piriform cortices (PIR), which are among the major olfactory areas
. To test this, we performed functional magnetic resonance imaging (fMRI) in anosmic patients with long-term smell loss due to infection before and after a 12-week olfactory training period.