Open Vocabulary Electroencephalography-To-Text Decoding and Zero-shot Sentiment Classification
Zhenhailong Wang, Heng Ji
TL;DR
The paper tackles open vocabulary brain–computer interfacing by decoding English text from noninvasive EEG signals using a pretrained language model (BART) as a core component, treating the brain as a text encoder. It introduces open vocabulary EEG-To-Text decoding and zero-shot EEG-based sentence sentiment classification, achieving a BLEU-1 of 40.1% and a zero-shot sentiment F1 of 55.6% on natural reading tasks. The approach maps EEG features to a latent space compatible with BART via an additional Transformer encoder, enabling generation from a large vocabulary ($| abla\mathcal{V}|\sim 50{,}000$) and transferable sentiment analysis without EEG–sentiment labels. The results demonstrate cross-subject robustness, improved performance with more diverse training data, and strong potential for noninvasive, high-coverage brain-to-text systems, with future work on larger datasets and multilingual inner speech decoding.
Abstract
State-of-the-art brain-to-text systems have achieved great success in decoding language directly from brain signals using neural networks. However, current approaches are limited to small closed vocabularies which are far from enough for natural communication. In addition, most of the high-performing approaches require data from invasive devices (e.g., ECoG). In this paper, we extend the problem to open vocabulary Electroencephalography(EEG)-To-Text Sequence-To-Sequence decoding and zero-shot sentence sentiment classification on natural reading tasks. We hypothesis that the human brain functions as a special text encoder and propose a novel framework leveraging pre-trained language models (e.g., BART). Our model achieves a 40.1% BLEU-1 score on EEG-To-Text decoding and a 55.6% F1 score on zero-shot EEG-based ternary sentiment classification, which significantly outperforms supervised baselines. Furthermore, we show that our proposed model can handle data from various subjects and sources, showing great potential for a high-performance open vocabulary brain-to-text system once sufficient data is available
