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. nature.com/articles/s41467-0… #parkinson #tremor @DBSThinkTank