iiinova — where your digital self keeps evolving

Moritz Gerster @moritz-gerster.bsky.social · 19/12/2025

𝐈𝐦𝐩𝐥𝐢𝐜𝐚𝐭𝐢𝐨𝐧: Mid gamma power is a promising medication-independent biomarker for adaptive deep brain stimulation—and it could be implemented in existing hardware (e.g., Medtronic Percept™ PC). Open-access paper: doi.org/10.1016/j.eb...

110

Moritz Gerster @moritz-gerster.bsky.social · 19/12/2025

𝐎𝐮𝐫 𝐚𝐩𝐩𝐫𝐨𝐚𝐜𝐡: We used aperiodic broadband power and mid gamma as LFP proxies for subthalamic firing. 𝐑𝐞𝐬𝐮𝐥𝐭: Aperiodic broadband power correlated with motor symptoms both OFF and ON medication. The same was true for mid gamma.

100

Moritz Gerster @moritz-gerster.bsky.social · 19/12/2025

Increased firing could so far only be confirmed 𝗱𝘂𝗿𝗶𝗻𝗴 surgery using microelectrodes, in the absence of Levodopa medication. Due to these technical constraints, most human studies have focused on beta and largely ignored the firing. We know Levodopa reduces beta – but how does it affect firing?

100

Moritz Gerster @moritz-gerster.bsky.social · 19/12/2025

Parkinson’s disease involves two major abnormalities in subthalamic nucleus activity: 1️⃣ Excessive beta (13–30 Hz) rhythms 2️⃣ Increased neuronal firing Beta can be measured 𝗮𝗳𝘁𝗲𝗿 surgery using deep brain stimulation electrodes.

130

Moritz Gerster @moritz-gerster.bsky.social · 15/12/2025

PS: This finding isn’t in the abstract and is easy to miss, so consider sharing it with colleagues working on automated DBS programming.

000

Moritz Gerster @moritz-gerster.bsky.social · 15/12/2025

𝐈𝐦𝐩𝐥𝐢𝐜𝐚𝐭𝐢𝐨𝐧: Absolute periodic high beta power could be used for automatic deep brain stimulation programming. Horn et al. 2017: doi.org/10.1002/hbm.... Darcy et al. 2022: doi.org/10.1016/j.ex... 𝐆𝐞𝐫𝐬𝐭𝐞𝐫 𝐞𝐭 𝐚𝐥. 𝟐𝟎𝟐𝟓: doi.org/10.1016/j.eb...

doi.org

Toward an electrophysiological “sweet spot” for deep brain stimulation in the subthalamic nucleus

You have to enable JavaScript in your browser's settings in order to use the eReader.

110

Moritz Gerster @moritz-gerster.bsky.social · 15/12/2025

1️⃣ Don’t normalize power spectra. Absolute beta power (µV²/Hz) performs better than relative “% of total power.” 2️⃣ Remove the aperiodic component using specparam. Isolating the periodic beta peaks improves the SNR. The high beta maps shrink toward the therapeutic sweet spot (blue sphere in video).

110

Moritz Gerster @moritz-gerster.bsky.social · 15/12/2025

𝐑𝐞𝐬𝐮𝐥𝐭: Correlation with the clinical sweet spot improved from 𝐫 = −𝟎.𝟐𝟑 → 𝐫 = −𝟎.𝟒𝟓 with two key changes in signal processing:

100

Moritz Gerster @moritz-gerster.bsky.social · 15/12/2025

𝐀𝐩𝐩𝐫𝐨𝐚𝐜𝐡: Natasha kindly shared her analysis code, and I replicated her correlation between high beta power and the therapeutic sweet spot in an independent cohort (Darcy et al.: 𝐫 = −𝟎.𝟐𝟎; replication: 𝐫 = −𝟎.𝟐𝟑).

100

Moritz Gerster @moritz-gerster.bsky.social · 15/12/2025

@andreashorn.org and @julianneumann.bsky.social proposed that the contact with the largest beta power in the STN could guide stimulation targeting. Natasha Darcy corroborated this in a large cohort, and I wondered whether optimized signal processing could strengthen the result further.

110

Moritz Gerster @moritz-gerster.bsky.social · 15/12/2025

Deep brain stimulation can improve Parkinson’s disease symptoms, but selecting the optimal stimulation contact still relies on laborious trial-and-error.

192

Moritz Gerster @moritz-gerster.bsky.social · 08/12/2025

Even simpler, band-averaged gamma power closely tracked aperiodic broadband power (ρ = 0.93). Taken together, the evidence suggests that invasively recorded gamma power can serve as a practical proxy for population firing. Open-access paper: doi.org/10.1016/j.eb...

100

Moritz Gerster @moritz-gerster.bsky.social · 08/12/2025

In our new paper, we separated oscillatory and aperiodic components and found that observed broadband shifts are mainly aperiodic – driven by flatter 1/f slopes and larger offsets. Therefore, we termed it “aperiodic broadband power”.

100

Moritz Gerster @moritz-gerster.bsky.social · 08/12/2025

Frustrated that I couldn’t measure firing directly in LFPs, I reviewed the studies that recorded both. To my surprise, a consistent pattern emerged: More firing → more broadband power.

100

Moritz Gerster @moritz-gerster.bsky.social · 08/12/2025

Yet most of our macroscopic recordings — EEG, MEG, ECoG, LFPs — mainly reflect postsynaptic transmembrane currents, i.e., the inputs to neurons. How do we reconcile measuring inputs while caring about outputs?

100

Moritz Gerster @moritz-gerster.bsky.social · 08/12/2025

A neuron can only do two things: Fire. Don’t fire. Firing is the neuron’s output, and most theories of neural computation treat that output as the brain's core information signal. 🧵

110

Moritz Gerster @moritz-gerster.bsky.social · 05/12/2025

Why? This is beautifully visualized in Fig. 1b of this classic paper: doi.org/10.1038/nrn3... In our recent publication, we show how scaling up to 119 patients across 4 hospitals strengthens biomarker discovery for adaptive deep brain stimulation in Parkinson’s disease: doi.org/10.1016/j.eb...

100

Moritz Gerster @moritz-gerster.bsky.social · 05/12/2025

Imagine you run an experiment with 50 subjects and find a significant effect just below p < 0.05. Another research group tries to replicate your finding, so they also recruit 50 people. If your methodology was perfect, what’s the chance the replication succeeds? 95%? 80%? It’s only 50% 🤯 👇🧵

120

Moritz Gerster @moritz-gerster.bsky.social · 05/12/2025

Thank you @mpicbs.bsky.social for covering our study! And thank you for fostering such an inspiring, intellectually vibrant, and genuinely supportive research environment — it was an exceptional place to do a PhD 🙏

000

Moritz Gerster @moritz-gerster.bsky.social · 17/06/2025

How does subthalamic nucleus activity relate to Parkinson’s disease symptoms? My last 5 years of Parkinson’s disease research summarized in 5 minutes at the DGKN Congress 2025 :) youtu.be/M9alDh836oU ⬇️ Full preprint: doi.org/10.1101/2025... #Parkinsonsdisease #Parkinsons #DeepBrainStimulation

youtu.be

Beyond beta rhythms - Moritz Gerster at DGKN Congress 2025

YouTube video by Moritz Gerster

052

Moritz Gerster @moritz-gerster.bsky.social · 02/05/2025

I am sincerely grateful to my supervisors–Vadim Nikulin, Gabriel Curio, Gunnar Waterstraat, and Arno Villringer–for their consistent support, guidance, and for shaping my approach to rigorous scientific work.

110

Moritz Gerster @moritz-gerster.bsky.social · 02/05/2025

I am deeply grateful to @julianneumann.bsky.social, @vlitvak.bsky.social, @ashwinioswal.bsky.social, Alfons Schnitzler, Esther Florin, Andrea Kühn, Jan Hirschmann, and Huiling Tan for sharing data and expertise, enabling me to synthesize their decades of experience into this work.

140

Moritz Gerster @moritz-gerster.bsky.social · 02/05/2025

#Aperiodic broadband power: ↳ Likely indicates neuronal spiking. ↳ Reflects symptom severity within patients. ↳ Shows promise as a biomarker for adaptive deep brain stimulation.

120

Moritz Gerster @moritz-gerster.bsky.social · 02/05/2025

#Powerspectrum analysis: ↳ Absolute power provides clearer insights than normalized power. ↳ Separating oscillations from the broadband improves interpretability. ↳ Theta & Low β & Low 𝛄 combined explained symptom severity better than beta alone.

110

Moritz Gerster @moritz-gerster.bsky.social · 02/05/2025

#Reproducibility analysis: ↳ Levodopa modulates theta more strongly than beta oscillations. ↳ Beta does not consistently correlate with symptoms in single datasets. ↳ Replicating previous correlations requires cohorts of over 100 patients.

120

Moritz Gerster @moritz-gerster.bsky.social · 02/05/2025

How does subthalamic activity relate to Parkinson’s disease symptoms? In a truly collaborative effort across #DBS centers, we aggregated a diverse dataset of invasive recordings from 119 patients. Full article: doi.org/10.1101/2025... Main findings 🧵⬇️

1127

Reposted by Moritz Gerster

Tristan Yates @tristansyates.bsky.social · 28/04/2025

We were blown away by the public response to our findings that the infant brain can store memories. Many people wrote to share with us their first memories. To help us capture these reports, we created a short, anonymous survey. We hope you might also consider taking it. Please share with others! 🧠🧪

yalesurvey.ca1.qualtrics.com

Survey of Earliest Memories

This survey pertains to your earliest memories. It is anonymous and all participation is voluntary.

02610

Reposted by Moritz Gerster

Thomas S. Binns @tsbinns.com · 18/02/2025

Excited to have my PhD project paper exploring the network mechanisms of neuromodulation accepted for publication! We show how deep brain stimulation and medication exert a shared modulation of motor network synchrony in Parkinson's disease.

Schematic summary of therapeutic effects of dopamine and deep brain stimulation (DBS) across spatial, spectral, and temporal scales in Parkinson's disease.

34716