arXiv Machine Learning

Which Metric Reflects the Spelling Rate Accuracy in Event-Related Potential-Based Brain-Computer Interfaces?

arXiv:2607. 00794v1 Announce Type: new Abstract: For predictive models, the often-reported performance metrics are the loss and accuracy.

arXiv Machine Learning
Sep 3

A Common Measure of Communication for Speech Brain-Computer Interfaces

The paper introduces Open‑Vocabulary Mutual Information (OVMI), an information‑theoretic metric that quantifies how much of a user’s intended speech a speech brain‑computer interface (BCI) can convey relative to a reference word distribution. OVMI enables comparison of systems that use different vocabularies, recording methods, and datasets, revealing that conventional metrics like accuracy and word error rate can overstate performance. Using OVMI, the authors compare existing speech BCI systems, expose trade‑offs between vocabulary coverage and decoding accuracy, and show that optimizing vocabulary selection for OVMI can improve accuracy by up to 16.3% across three speech domains.

By Dulhan Jayalath, Benjamin Ballyk, Oiwi Parker Jones
arXiv Machine Learning
Sep 11

When More Is Not Better: Component Anti-Synergy in a P300 Speller

The study investigates whether adding more components to a P300 brain‑computer interface speller always improves performance. Using a full‑factorial experiment on a public dataset, the authors varied Euclidean Alignment, xDAWN spatial filtering, subject calibration, and language model priors, and found that component effects are conditional rather than additive. Calibration was the most influential, while adding components could sometimes reduce performance, demonstrating component anti‑synergy and challenging the assumption that an ‘all‑on’ pipeline is best.

By Lucas Yang, Rui Liu, Fusheng Wang
arXiv Machine Learning
Jul 28

Bayesian Complete-Pooling in Cross-Subject Classification for Motor Imagery Electroencephalogram

arXiv:2607. 22980v1 Announce Type: new Abstract: Brain-computer interfaces (BCIs) have long sought calibration-free operation, but classifiers are typically benchmarked by discrimination alone, blind to whether predicted probabilities are well calibrated - a meaningful gap given nonstationary electroencephalogram (EEG) signals and the risk of overconfident point-estimate classifiers under distribution shift.

By Ethan Davis
arXiv AI
3d ago

NeuroAtlas: Benchmarking Foundation Models for Clinical EEG and Brain-Computer Interfaces

NeuroAtlas is the largest EEG benchmark to date, comprising 42 datasets and 260,000 hours of clinical EEG data across epilepsy, sleep medicine, brain age estimation, and brain‑computer interfaces. The study evaluates foundation models (FMs) for EEG against supervised baselines and generic time‑series FMs, finding that EEG‑specific FMs do not consistently outperform generic ones. It also demonstrates that standard machine‑learning metrics are inadequate for clinical relevance, advocating for task‑specific measures such as event‑level decision quality, hypnogram features, and brain‑age gap.

By Konstantinos Kontras, Trui Osselaer, Stylianos G. Mouslech, Angeliki-Ilektra Karaiskou, Guido Gagliardi, Thomas Strypsteen, Mohammad Hossein Badiei, Anku Rani, Maarten Vanmarcke, Miguel Bhagubai, Chanakya Ekbote, Jaedong Hwang, Christos Chatzichristos, Paul Pu Liang, Maarten De Vos
arXiv Machine Learning
Sep 4

The 2026 PNPL Competition: Word Classification and Efficient Cross-Subject Generalisation in LibriBrain100

The 2026 PNPL Competition builds on the 2025 PNPL effort by expanding the LibriBrain dataset to 32 new subjects and more within‑subject data, creating LibriBrain100. It introduces two tracks: a Deep track for high‑performance within‑subject word classification and a Broad track that tests cross‑subject generalisation with progressively less subject‑specific fine‑tuning data, down to 10 minutes. The competition aims to advance non‑invasive brain‑computer interfaces toward practical, clinically feasible communication restoration for people with profound paralysis.

By Francesco Mantegna, Gereon Elvers, Dulhan Jayalath, Gilad Landau, Tasha Kim, Miran \"Ozdogan, Luisa Kurth, Teyun Kwon, SungJun Cho, Benjamin Ballyk, Alex Fung, Anna Greer, Pratik Somaiya, Christian Herff, Yorguin Mantilla Ramos, Hamza Abdelhedi, Karim Jerbi, Greg Farquhar, Brendan Shillingford, Mark Woolrich, Oiwi Parker Jones
arXiv AI
Aug 24

The Divergence Hypothesis: Unmasking Lexical Interference and Label Bias in Mental Health NLP

The paper introduces TSS (Triple-Stream Stress probe), a diagnostic framework that splits text into lexical, morpho-syntactic, and psycholinguistic style channels to analyze mental health NLP classifiers. Across four English datasets, TSS uncovers a lexical interference effect where adding lexical features harms performance on human-labeled data but not on auto-labeled data, and proposes the Degree of Divergence (DoD) statistic to audit label-source bias. The study demonstrates that style features largely remain effective even after masking content words, emphasizing that shortcut learning is label-source specific rather than clinically relevant.

By Moustafa Yehia Hassan