2,123 research outputs found
Neural decoding using a nonlinear generative model for brain-computer interface
pre-printKalman filters have been used to decode neural signals and estimate hand kinematics in many studies. However, most prior work assumes a linear system model, an assumption that is almost certainly violated by neural systems. In this paper, we show that adding nonlinearities to the decoding algorithm improves the accuracy of tracking hand movements using neural signal acquired via a 32-channel micro-electrocorticographic (ÎĽECoG) grid placed over the arm and hand representations in the motor cortex. Experimental comparisons indicate that a Kalman filter with a fifth order polynomial generative model relating the hand kinematics signals to the neural signals improved the mean-square tracking performance in the hand movements over a conventional Kalman filter employing a linear system model. This finding is in accord with the current neurophysiological understanding of the decoded signals
Cancer diagnosis using deep learning: A bibliographic review
In this paper, we first describe the basics of the field of cancer diagnosis, which includes steps of cancer diagnosis followed by the typical classification methods used by doctors, providing a historical idea of cancer classification techniques to the readers. These methods include Asymmetry, Border, Color and Diameter (ABCD) method, seven-point detection method, Menzies method, and pattern analysis. They are used regularly by doctors for cancer diagnosis, although they are not considered very efficient for obtaining better performance. Moreover, considering all types of audience, the basic evaluation criteria are also discussed. The criteria include the receiver operating characteristic curve (ROC curve), Area under the ROC curve (AUC), F1 score, accuracy, specificity, sensitivity, precision, dice-coefficient, average accuracy, and Jaccard index. Previously used methods are considered inefficient, asking for better and smarter methods for cancer diagnosis. Artificial intelligence and cancer diagnosis are gaining attention as a way to define better diagnostic tools. In particular, deep neural networks can be successfully used for intelligent image analysis. The basic framework of how this machine learning works on medical imaging is provided in this study, i.e., pre-processing, image segmentation and post-processing. The second part of this manuscript describes the different deep learning techniques, such as convolutional neural networks (CNNs), generative adversarial models (GANs), deep autoencoders (DANs), restricted Boltzmann’s machine (RBM), stacked autoencoders (SAE), convolutional autoencoders (CAE), recurrent neural networks (RNNs), long short-term memory (LTSM), multi-scale convolutional neural network (M-CNN), multi-instance learning convolutional neural network (MIL-CNN). For each technique, we provide Python codes, to allow interested readers to experiment with the cited algorithms on their own diagnostic problems. The third part of this manuscript compiles the successfully applied deep learning models for different types of cancers. Considering the length of the manuscript, we restrict ourselves to the discussion of breast cancer, lung cancer, brain cancer, and skin cancer. The purpose of this bibliographic review is to provide researchers opting to work in implementing deep learning and artificial neural networks for cancer diagnosis a knowledge from scratch of the state-of-the-art achievements
Large-scale Foundation Models and Generative AI for BigData Neuroscience
Recent advances in machine learning have made revolutionary breakthroughs in
computer games, image and natural language understanding, and scientific
discovery. Foundation models and large-scale language models (LLMs) have
recently achieved human-like intelligence thanks to BigData. With the help of
self-supervised learning (SSL) and transfer learning, these models may
potentially reshape the landscapes of neuroscience research and make a
significant impact on the future. Here we present a mini-review on recent
advances in foundation models and generative AI models as well as their
applications in neuroscience, including natural language and speech, semantic
memory, brain-machine interfaces (BMIs), and data augmentation. We argue that
this paradigm-shift framework will open new avenues for many neuroscience
research directions and discuss the accompanying challenges and opportunities
Deep learning for healthcare applications based on physiological signals: A review
Background and objective: We have cast the net into the ocean of knowledge to retrieve the latest scientific research on deep learning methods for physiological signals. We found 53 research papers on this topic, published from 01.01.2008 to 31.12.2017. Methods: An initial bibliometric analysis shows that the reviewed papers focused on Electromyogram(EMG), Electroencephalogram(EEG), Electrocardiogram(ECG), and Electrooculogram(EOG). These four categories were used to structure the subsequent content review. Results: During the content review, we understood that deep learning performs better for big and varied datasets than classic analysis and machine classification methods. Deep learning algorithms try to develop the model by using all the available input. Conclusions: This review paper depicts the application of various deep learning algorithms used till recently, but in future it will be used for more healthcare areas to improve the quality of diagnosi
A study on decoding models for the reconstruction of hand trajectories from the human magnetoencephalography
Decoding neural signals into control outputs has been a key to the development of brain-computer interfaces (BCIs). While many studies have identified neural correlates of kinematics or applied advanced machine learning algorithms to improve decoding performance, relatively less attention has been paid to optimal design of decoding models. For generating continuous movements from neural activity, design of decoding models should address how to incorporate movement dynamics into models and how to select a model given specific BCI objectives. Considering nonlinear and independent speed characteristics, we propose a hybrid Kalman filter to decode the hand direction and speed independently. We also investigate changes in performance of different decoding models (the linear and Kalman filters) when they predict reaching movements only or predict both reach and rest. Our offline study on human magnetoencephalography (MEG) during point-to-point arm movements shows that the performance of the linear filter or the Kalman filter is affected by including resting states for training and predicting movements. However, the hybrid Kalman filter consistently outperforms others regardless of movement states. The results demonstrate that better design of decoding models is achieved by incorporating movement dynamics into modeling or selecting a model according to decoding objectives.open0
Generate your neural signals from mine: individual-to-individual EEG converters
Most models in cognitive and computational neuroscience trained on one
subject do not generalize to other subjects due to individual differences. An
ideal individual-to-individual neural converter is expected to generate real
neural signals of one subject from those of another one, which can overcome the
problem of individual differences for cognitive and computational models. In
this study, we propose a novel individual-to-individual EEG converter, called
EEG2EEG, inspired by generative models in computer vision. We applied THINGS
EEG2 dataset to train and test 72 independent EEG2EEG models corresponding to
72 pairs across 9 subjects. Our results demonstrate that EEG2EEG is able to
effectively learn the mapping of neural representations in EEG signals from one
subject to another and achieve high conversion performance. Additionally, the
generated EEG signals contain clearer representations of visual information
than that can be obtained from real data. This method establishes a novel and
state-of-the-art framework for neural conversion of EEG signals, which can
realize a flexible and high-performance mapping from individual to individual
and provide insight for both neural engineering and cognitive neuroscience.Comment: Proceedings of the 45th Annual Meeting of the Cognitive Science
Society (CogSci 2023
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