Stopped by @karaannjohnson poster, from 2022 Stanley Fahn Awardee @coradehemptinne lab, who is investigating neurophysiological markers of depression from recordings taken during DBS surgery for PD. An important topic!

Can you induce an elevated mood by subthalamic nucleus deep brain stimulation (STN DBS) settings? You bet you can and Coutinho, Johnson, de Hemptinne and colleagues share a great case @tremorjournal. Key Points: - The authors remind us that STN DBS may occasionally be associated with 'undesirable psychiatric adverse effects, including elevated mood.' - This person had bilateral STN DBS and experienced stimulation-induced elevated mood. - There was a correlation between 'mood changes and enhanced activation of the ventromedial region of the left STN DBS.' My take: These episodes trevealed stimulation-induced events which manifested contemporaneously or shortly following DBS programming. The authors point out that there may have been a risk factor in the baseline mild impulse control symptoms and hypersexuality. Because episodes of mood elevation were 'acute, reversible, and associated with changes in stimulation parameters' this phenomenon will be important for clinicians to appreciate. Additionally, reductions in levodopa therapy may also be useful in the management process. Clinicians should also be aware that mood elevation and hypomania may occur following DBS, and if you have yet to encounter a case, consider the possibility you may have missed the diagnosis. My advice for clinicians managing folks in the first few weeks/months following DBS surgery is to approach management of the case w/ arrectīs auribus – w/ ears pricked up, for hints that the 'response to therapy may be too good' (e.g. euphoria, hypomania, euphoria). #Parkinsons @DBSThinkTank #Subthalamic #deepbrainstimulation

Ever wonder how circadian rhythms are tracked in the brain? These rhythms represent the physical, mental, and behavioral changes experienced over a 24 hour cycle. Thus, it isn't just 'light and dark' which affect these rhythms and guess what? You can measure them in the human GPi and STN if you happen to have a specific type of DBS in your brain. This study @CagleJackson and de Hemptinne in @NatureComms is pretty cool. Key Points: - This study examined GPi circadian rhythms in a large cohort of subjects with PD. - They collected 130 recordings from 93 subjects. - GPi activity was recorded in their home environment. - There was a significant change in GPi activity between day and night in 82%. - There was a reduction in GPi activity at night in over half of recordings. Interestingly, there was an increase in activity in about a quarter. My view: It is really important that we recognize that circadian fluctuations are present and can be monitored from activity in the GPi (and also in the STN). There are important clues hidden in these brain tracings. Re-emergence of pathological neural activity is an important clue in understanding disruptions in the sleep cycle. This may help explain why when we re-dose sinemet at 2-3 AM it is helpful for folks to get back to sleep. Looking forward to more studies to further enlighten us on circadian patterns recorded from subcortical structures. #parkinson #tremor @DBSThinkTank

Do you know the two main approaches to guide programming deep brain stimulation? Neurophysiology and neuroimaging as ⁦@karaannjohnson⁩ delightfully blew our minds showing how ERNA could possibly be used to bridge gaps; guide clinicians of the future. ⁦@ASSFNeurosurg⁩

Kara Johnson kicked off the week w/ a presentation on her work using evoked resonant neural activity (ERNA) which is a high-frequency (∼200–500 Hz) stimulation evoked response has been proposed as a candidate neural signal in deep brain stimulation (DBS) for Parkinson's disease. ERNA has been hypothesized to originate from reciprocal connections between the STN and the pallidum, although its exact origins are unclear. Studies of STN DBS have suggested that ERNA may be localized to the therapeutic target region and may be correlated with postoperative stimulation parameters and possibly reduction in motor symptoms in Parkinson’s disease. @karaannjohnson @DBSThinkTank #parkinson #deepbrainstimulation #neuromodulation