Region Specific Analysis
The hippocampus is important in odor-evoked memory, meaning that its connection to olfactory structures could possibly aid or induce its plasticity following STN-DBS. Furthermore, in PD patients, it is olfactory identification that is usually improved with STN-DBS, indicating the involvement of higher brain regions involved in memory such as the hippocampus.
In PD patients, the lateral orbitofrontal cortex holds importance with its involvement in higher olfactory processing such as odor discrimination. Furthermore, with the convergence of gustatory and olfaction taking place in the OFC, it would be no surprise if STN-DBS induced volumetric changes in this structure
Olfactory bulb is not only a site of neurogenesis, but also receives dopaminergic input; therefore, changes in its volume that have been shown to parallel with olfactory recovery should be expected with STN-DBS. Furthermore, with its role in being a phenotypical marker to signify olfactory dysfunction in PD patients, we decided to track changes in OB volume with length of stimulation to determine if this structure can be a predictive marker of olfactory recovery following stimulation.