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Unveiling Hidden Neural Codes: SIMPL – A Scalable and Fast Approach for Optimizing Latent Variables and Tuning Curves in Neural Population Data

Dr. Rishabh Pathak
This research paper presents SIMPL (Scalable Iterative Maximization of Population-coded Latents), a novel, computationally efficient algorithm designed to refine the estimation of latent variables and tuning curves from neural population activity. Latent variables in neural data represent essential low-dimensional quantities encoding behavioral or cognitive states, which neuroscientists seek to identify to understand brain computations better. Background and Motivation Traditional approaches commonly assume the observed behavioral variable as the latent neural code. However, this assumption can lead to inaccuracies because neural activity sometimes encodes internal cognitive states differing subtly from observable behavior (e.g., anticipation, mental simulation). Existing latent variable models face challenges such as high computational cost, poor scalability to large datasets, limited expressiveness of tuning models, or difficulties interpreting complex neural network-based functio...
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Glossokinetic Artifacts

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Dr. Rishabh Pathak

Glossokinetic artifacts in EEG recordings are a type of artifact related to movements of the tongue muscles. 

1.     Description:

o    Glossokinetic artifacts are artifacts caused by movements of the tongue muscles, which can introduce electrical activity that contaminates the EEG signal.

2.   Characteristics:

o Location: Glossokinetic artifacts typically affect electrodes near the mouth or tongue region where the muscle movements are occurring.

o Amplitude: The amplitude of glossokinetic artifacts may vary depending on the intensity of tongue movements and the proximity to the recording electrodes.

3.   Identification:

o Glossokinetic artifacts can be identified by their association with specific muscle movements in the tongue region and their distinct waveform characteristics.

o These artifacts may manifest as sudden changes in the EEG signal coinciding with tongue movements.

4.   Clinical Relevance:

oRecognizing glossokinetic artifacts is important for distinguishing them from genuine brain activity during EEG interpretation.

o  Failure to identify and differentiate glossokinetic artifacts can lead to misinterpretation of EEG findings and incorrect clinical assessments.

5.    Artifact Mitigation:

oStrategies to mitigate glossokinetic artifacts include minimizing movements in the tongue region during EEG recordings and ensuring proper electrode placement to reduce artifact contamination.

oSignal processing techniques, such as artifact removal algorithms, can also help in reducing the impact of glossokinetic artifacts on EEG data quality.

Understanding the characteristics and implications of glossokinetic artifacts is essential for EEG technologists and clinicians to ensure accurate interpretation of EEG recordings and reliable clinical assessments. Proper identification and management of glossokinetic artifacts contribute to obtaining high-quality EEG data for effective diagnosis and treatment planning.

 

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