Questions tagged [eeg]

The recording of voltages along the scalp for the purpose of monitoring brain wave activity and localizing sources of ionic currents

Filter by
Sorted by
Tagged with
0
votes
1answer
21 views

Should i normalize FFT signal with z-score?

I am working with EEG data (time domain) in a machine learning task, where each input signal must be mapped to a class/frequency. I am using FFT in order to get data in frequency domain and make ...
0
votes
0answers
7 views

Can you create epochs between 2 triggers rather than based on time in MNE?

MNE's parameters available for selecting intervals for an epoch are based on time around a trigger (tmin, tmax). However, my experiment features videos of varying lengths, and I have triggers to mark ...
0
votes
1answer
27 views

How does ICA works with more than two sources

In all tutorials on ICA that i've seen, two sources are separated from each other. but how is two source separation different from multi-source separations like data recorded by EEG hats ?
0
votes
0answers
20 views

How can I extract P300 from a continuous EEG dataset?

I have a continuous EEG dataset from the MUSE EEG headset. I need to extract the p300 events from the headset. Is there any standard algorithm / open source project for the extraction of the p300 ...
0
votes
1answer
20 views

Regularity in EEG data

I've just started looking into EEG data using a Muse s and mind monitor. I've noted this very regular 4 Hertz (approximately) pattern and wonder if this is real or an artifact. Is it just a very ...
1
vote
1answer
37 views

EEG peaks do not get identified at the correct frequencies

For my thesis I am re-analyzing a dataset where subjects were visually stimulated with 5.45, 8.57, 12 or 15 Hz. This well-known technique (steady state visual evoked potential) should elicit EEG peaks ...
0
votes
1answer
38 views

Extracting EEG Bands from raw EEG signal to match with the Bands calculated on the sensor level

I have recently got my hands on a commercially available single channel EEG Sensor from Neurosky. This sensor acquire raw EEG signal at 512Hz from the frontal part of the human head and also process ...
0
votes
0answers
17 views

EEG Data Analysis

I have recorded EEG data using openBCI which is in the range of -15000 to 15000 micro volts. I want to reduce this to the range of -100 to 100 micro volts. How do I do it?
0
votes
0answers
25 views

Breaking EEG signal into epochs: why should we multipy windows-time length by frequency?

I am new to EEG data, Could you please explain why we need to multiply Fs by window_time_length ? I thought by defining window_time_length, we define the length of epoch! I am working on P300 BCI ...
2
votes
1answer
154 views

MATLAB's designfilt vs butter function

I am relatively new to signal processing, and have always used MATLAB's designfilt option for my signal processing needs. Recently, however, I have seen people just using MATLAB's butter function. ...
0
votes
1answer
35 views

mne raw plot looks like vertical lines instead of the usual signal

I have a data from a single eeg channel. When I plot it with plt, it looks like a regular signal. However, when I'm trying to plot with mne raw object's method plot, it looks very strange, like ...
0
votes
0answers
13 views

Is my interpretation of CAR filter correct?

I am a computer scientist working on a Brain-Computer Interface (BCI) project. So, i am using EEG data from a dataset and classifying them with the use of machine learning algorithms. Initial results ...
2
votes
0answers
121 views

Edge artifacts in frequency-domain Moving Average filter

I am currently trying to implement in python an algorithm to identify and filter out one specific periodic EEG artifact -- the grad fMRI artifact -- as described in this paper, and I am incurring in ...
0
votes
0answers
23 views

Logic analyzer for acquiring EEG signals?

Is it possible? I haven't found anything about it on the internet. I found a logic analyzer here, which is marketed as having the capability to monitor analog signals too: "One useful feature of ...
0
votes
2answers
86 views

Processes/Transforms involved to get brainwave data from raw EEG? (Autocorrelation confusion)

Not clear on what the autocorrelation function of raw EEG means physically why can't you take the FT of a the EEG itself and get frequency data? With BCI & basic electrode setups you can ...
0
votes
0answers
40 views

Does my filter desing for unusual EEG experiment looks good?

I have made some progress since my last question, and again I am asking you for advice. Hi, I'm still designing an unusual (in terms of signal analysis) EEG experiment, which forces me to design my ...
0
votes
0answers
15 views

Use of spectrograms in using deep learning on EEG related problems

I am currently working on a classification problem related to EEG signals. My professor asked me to convert those signals into their spectrograms and try various convolutional neural networks on them. ...
0
votes
0answers
42 views

Deep Learning for Online EEG Denoising

I'm currently working on the development of deep learning methods for online artifact removal from EEG signals. I'm interested in removing common biological artifacts such as EOG and EMG individually ...
0
votes
0answers
51 views

How to install FCLAB for EEG connectivity calculation

I am doing about another person question here, so the question is: How I could do EEG functional connectivity calculation by Matlab? So I have googled the EEG functionality and find two plugin by ...
0
votes
1answer
47 views

Filter design for an unusual EEG experiment

I'm designing a quite unusual (in terms of signal analysis) EEG experiment, which forces me to design my own filter. I have never done this before, so kindly please check my work and suggest ...
0
votes
0answers
29 views

Source Localization in the context of EEG

I am having difficulty understanding how source localization is used in Brain-Computer Interface (BCI) as a feature extraction method. As a bit of introduction, the measured activity (Matrix M) is a ...
0
votes
2answers
107 views

why is the signal divided into epochs in EEG classification?

I'm new in EEG signal classification. Studying the literature on this topic, I wonder why the EEG signals are divided in epochs, so, instead of classifying the whole signal all at once, we usually ...
0
votes
0answers
27 views

Object for storing multiple trials of EEG MNE-python

I'm new to EEG and MNE. I'm looking for an MNE object to store data from many trials (trails * channels * times). I've noticed that I can use Epochs for that, and it works ok, but I wasn't sure if ...
0
votes
0answers
57 views

DWT and FFT on a very low frequency signals

I am trying to extract features from a very low frequency signal of $0.1$ HZ and less than $100$ samples. Is it advisable to use FFT and DWT on this signal?
0
votes
0answers
77 views

EEGLab import .mat file

I am new to EEG and signal processing, anyone can please check if I fill in the right numbers? I am confused about those terms. For example, the recording using 22 EEG channels and 3 EOG channels, ...
0
votes
1answer
113 views

Wrong values calculating FFT with EEG Bands using Numpy

First of all I have to say I am very new to these matters. I am trying to apply FFT algorithm to some values obtained by EEG bands. I found the following code but I am unable to make it work correctly....
2
votes
1answer
131 views

EEG signal processing with wavelet or fft?

I have confusion about signal processing related with EEG signal. I have done some of my research and that made me more confused about processing and filtering the signal. Let me jump into the problem ...
1
vote
1answer
87 views

Filtering artefacts and filtering short signals

I have a signal from EEG sensors and I try to denoise it from AC frequencies. For that reason, I estimated PSD of my signal and found that 50 Hz and 100 Hz are likely to represent noise. I constructed ...
0
votes
1answer
106 views

How to determine a suitable threshold when using amplitude thresholding method for spike detection?

I have seen number of approaches that have been introduced in the literature for spike detection including, amplitude thresholding method, Nonlinear Energy Operator method, and template matching ...
1
vote
2answers
75 views

Comparing similarity of two simultaneously recorded EEGs in freq domain

I have two EEG signals that are simultaneously recorded during the night (sleep). Imagine one device recorded from channel F4 and the other from Fp2. Now I would like to check the similarity of these ...
0
votes
0answers
21 views

How can a CNN account for spectro-temporal constraints in neural data?

What are there the best ways to leverage the unique "geometrical" constraints of spectro-temporal signal representations (architecture, filter shapes, data augmentation, etc.)? For example, ...
2
votes
1answer
193 views

Baseline correction for continuous EEG signals

I'm new to the topic so forgive the trivial question. I am trying to understand data preprocessing for EEG signals. As I understand, after recording continuous EEG signals, they should be band-pass ...
1
vote
0answers
40 views

VHF Artifact Contaminating Electrophysiological Sleep Signals

I am trying to remove an artifact from a VHF transmitter (programmed at a frequency of 148535; 1.5sec between 200ms pulses; 1.7sec peak to peak) from a sleep recording (polysomnography recording with ...
0
votes
0answers
41 views

Classifying motor imagery from EEG data: Feature selection

I am an undergraduate student who is trying to classify motor imagery from EEG data! I have no experience working with EEG or any neuroscience background, I only have a very basic knowledge of how ...
0
votes
0answers
63 views

Should A/D resolution affect EEG signal properties and how?

I encounter a curious situation wherein the recording device of my EEG data appears to affect how many transients of definition "x" I find, especially strange since the amplitude criterion is relative ...
0
votes
0answers
335 views

EEG signal windowing and framing in python

I would like to do EEG signal(using 1 channel) Windowing and Framing. Actually I am doing my thesis and following a research paper.In this paper they explained "Windowing consists of dividing ...
-1
votes
2answers
566 views

How to get Spectrogram after fft in matlab?

I have many EEG signals which record at 100 Hz. I use FFT on them with fft Matlab toolbox. Now I wanted to get a Spectrogram. As I searched and read a lot, I figure that I should window my signal and ...
0
votes
0answers
247 views

How to separate EEG frequency band in python?

Sorry for stupid question! I am very new in EEG signal processing and python environment.I have started my a project work related to EEG signal analysis using MNE. I would like to separate EEG Bands ...
1
vote
2answers
3k views

Difference between bandpass filter and using fast fourier transform to extract power of frequency bands

In signal processing, I have heard of two terms: Using band-pass filter to extract some frequency bands. Using Discrete/Fast Fourier Transform (DFT/FFT) to extract some frequency bands. Are these ...
0
votes
2answers
72 views

Extracting different frequency bands (alpha, beta, gamma) from brain activity data

I am new to signal processing and despite googling about my question, I still couldn't find the solution. I have an Electrocorticography (ECoG) dataset. This consists of recording brain activity from ...
0
votes
0answers
63 views

frequency amplitude asymmetry

I want to calculate the frequency amplitude asymmetry between two signals, EEG signals in particular. As a result, I expect a value ranging from 0 to 1. I have some references regarding that, but it's ...
0
votes
0answers
46 views

Using unlabeled EEG data for Machine Learning

I am working on a project that is basically a game for motor-paralyzed people. It should take an EEG signal from FP1 channel of brain and then after processing it should generate command for the game ...
3
votes
0answers
95 views

How to compare imaginary coherence values?

High, I am currently writing my Master's thesis on susceptibility for hypnosis. I am comparing EGG signals of lowly and highly susceptible individuals. The imaginary coherence is given by: $$ \...
3
votes
1answer
432 views

What Is Meant by Clustering of ICA (Independent Component Analysis) Components?

I'm following the EEGLAB tutorial about STUDY creation and manipulation of the datasets, and came across the concept of clustering of ICA components. I'm not too familiar with processing of ICA ...
0
votes
1answer
4k views

Python tool for time-frequency analysis

I am trying to perform time-frequency analyses using the PyWavelets (pywt) toolkit for python. My ultimate goal is to perform time-frequency analyses for EEG signals but I am starting with something ...
0
votes
1answer
212 views

Can Kalman filter remove 50 Hz noise?

I'm dealing with a brain stimulation. My EEG contains large spikes (>3 mV) when stimulation occurs. I want to remove the 50 Hz noise, but I can't use notch filter because it creates large artifacts. ...
0
votes
0answers
400 views

How to find Coefficients of Autoregressive (AR) model using least means square (LMS) Algorithm without having future signal?

I want to do two things. Estimating Coefficients of AR model using LMS Using Coefficients found in step 1 and predict future samples of a signal using AR equation. I don't have a desired signal so I ...
0
votes
1answer
177 views

How to apply baseline methods to MNE preprocessed raw EEG signals?

I am new at EEG preprocessing and classification. I have followed Clemens Brunner's blog https://cbrnr.github.io/2018/01/29/removing-eog-ica/ as a tutorial for MNE. This is how I have preprocessed ...
2
votes
2answers
226 views

Augmentation for EEG signal classification using Deep Learning

Augmentation is a technique that we use in deep learning for expanding the training dataset. It includes different ways of modifying an image and adding it to the training dataset. My question is if ...
1
vote
0answers
69 views

How to account for number of electrodes in EEG data while converting to frequency domain?

I have raw data from 64 electrode EEG in CSV format where there are multiple rows and 64 columns. I am using the following Python code to separate the data into frequency bands: ...