I am currently a postdoc fellow at Large-scale network connectivity in the human brain lab, Karolinsk Institutet. I research on invasive as well as non-invasive brain imaging using diverse analytic tools.
I have developed a non-invasive method, so-called electrobulbogram (EBG), to record from human olfactory bulb (OB). In this method we placed 4 active electordes on the forehead of individuls following the outline of their eyebrows. Assessing the spectogram reveals that EBG can detect the charactrestic gamma oscillations of OB. We have further validate this method in several expeiments.Non-invasive recording from the human olfactory bulb. Iravani B, Arshamian A, Ohla K, Wilson DA, Lundström JN Nat Commun 2020 01;11(1):648
Our EBG method has shown promisng results where we could demonestrate that odor valence processing during the first sniff in human is a seuqntial process consisiting of early and late processes. The oscillatory behavior of these processes are different, so does their functional role. Specifically we indicated that the early process cues avodiance motor response in humans.The human olfactory bulb processes odor valence representation and cues motor avoidance behavior. Iravani B, Schaefer M, Wilson DA, Arshamian A, Lundström JN Proc Natl Acad Sci U S A 2021 Oct;118(42):
Moreover, using EBG we further demonestrated that the odor identity can be deciphered from the connectivity between OB and piriform cortex (PC) as early as 100ms post odor onset. We also found that the oscillation in the OB-PC connectivity evolves from fast gamma oscillations to slower theta oscillation during late time points. Additionally, the afferent and efferent connections of OB-PC is found to oppearate in gamma/beta and delta/theta respectively. Odor identity can be extracted from the reciprocal connectivity between olfactory bulb and piriform cortex in humans. Iravani B, Arshamian A, Lundqvist M, Kay LM, Wilson DA, Lundström JN Neuroimage 2021 08;237():118130.
Given that OB is the first area of insult in Parkinson disease (PD), measuring the OB function seems to be a relevant candidate for early diagnosis of PD. Yet there was no non-invasive method to measure OB function in human until we developed EBG. Using EBG we demonstrated that the differences in the oscillator olfcatory processes during the first sniff can dissociate PD patients from age-matche healty controls with sensitivity of 90% and specificity of 100%, values comparable to clinical odo identification test. Consquently, this finding puts EBG as potentially best method for early diagnosis of PD that has to be validated in future works. A non-invasive olfactory bulb measure dissociates Parkinson's patients from healthy controls and discloses disease duration. Iravani B, Arshamian A, Schaefer M, Svenningsson P, Lundström JN NPJ Parkinsons Dis 2021 Aug;7(1):75