This repository contains the code and data necessary to reproduce the results of the paper ["*An Accurate and Rapidly Calibrating Speech Neuroprosthesis*" by Card et al. (2024), *N Eng J Med*](https://www.nejm.org/doi/full/10.1056/NEJMoa2314132).
The code is written in Python, and the data can be downloaded from Dryad, [here](https://datadryad.org/stash/dataset/doi:10.5061/dryad.dncjsxm85). Please download this data and place it in the `data` directory before running the code. Be sure to unzip `t15_copyTask_neuralData.zip` and `t15_pretrained_rnn_baseline.zip`.
- The `utils` directory contains utility functions used throughout the code.
- The `analyses` directory contains the code necessary to reproduce results shown in the main text and supplemental appendix.
- The `data` directory contains the data necessary to reproduce the results in the paper. Download it from Dryad using the link above and place it in this directory.
- The `model_training` directory contains the code necessary to train and evaluate the brain-to-text model. See the README.md in that folder for more detailed instructions.
- The `language_model` directory contains the ngram language model implementation and a pretrained 1gram language model. Pretrained 3gram and 5gram language models can be downloaded [here](https://datadryad.org/dataset/doi:10.5061/dryad.x69p8czpq) (`languageModel.tar.gz` and `languageModel_5gram.tar.gz`). See [`language_model/README.md`](language_model/README.md) for more information.
- 512 neural features (2 features [-4.5 RMS threshold crossings and spike band power] per electrode, 256 electrodes), binned at 20 ms resolution. The data were recorded from the speech motor cortex via four high-density microelectrode arrays (64 electrodes each). The 512 features are ordered as follows in all data files:
- Data for each session/split is stored in `.hdf5` files. An example of how to load this data using the Python `h5py` library is provided in the [`model_training/evaluate_model_helpers.py`](model_training/evaluate_model_helpers.py) file in the `load_h5py_file()` function.
- Each block of data contains sentences drawn from a range of corpuses (Switchboard, OpenWebText2, a 50-word corpus, a custom frequent-word corpus, and a corpus of random word sequences). Furthermore, the majority of the data is during attempted vocalized speaking, but some of it is during attempted silent speaking.
-`t15_pretrained_rnn_baseline.zip`: This dataset contains the pretrained RNN baseline model checkpoint and args. An example of how to load this model and use it for inference is provided in the [`model_training/evaluate_model.py`](model_training/evaluate_model.py) file.
Please download these datasets from [Dryad](https://datadryad.org/stash/dataset/doi:10.5061/dryad.dncjsxm85) and place them in the `data` directory. Be sure to unzip both datasets before running the code.
- The code has only been tested on Ubuntu 22.04 with two NVIDIA RTX 4090 GPUs.
- We recommend using a conda environment to manage the dependencies. To install miniconda, follow the instructions [here](https://docs.anaconda.com/miniconda/miniconda-install/).
- Redis is required for communication between python processes. To install redis on Ubuntu:
-`CMake >= 3.14` and `gcc >= 10.1` are required for the ngram language model installation. You can install these on linux with `sudo apt-get install cmake` and `sudo apt-get install build-essential`.
We use an ngram language model plus rescoring via the [Facebook OPT 6.7b](https://huggingface.co/facebook/opt-6.7b) LLM. A pretrained 1gram language model is included in this repository at [`language_model/pretrained_language_models/openwebtext_1gram_lm_sil`](language_model/pretrained_language_models/openwebtext_1gram_lm_sil). Pretrained 3gram and 5gram language models are available for download [here](https://datadryad.org/dataset/doi:10.5061/dryad.x69p8czpq) (`languageModel.tar.gz` and `languageModel_5gram.tar.gz`). Note that the 3gram model requires ~60GB of RAM, and the 5gram model requires ~300GB of RAM. Furthermore, OPT 6.7b requires a GPU with at least ~12.4 GB of VRAM to load for inference.
Our Kaldi-based ngram implementation requires a different version of torch than our model training pipeline, so running the ngram language models requires an additional seperate python conda environment. To create this conda environment, run the following command from the root directory of this repository. For more detailed instructions, see the README.md in the [`language_model`](language_model) subdirectory.