Questions tagged [signal-processing]
Signal Processing covers the theory, algorithms, performance analyses and applications of techniques for the processing, understanding, learning, retrieval, mining, and extraction of information from signals (1, 2)
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Neurons: how does the brain reduce electromagnetic interference?
I read that the frequency of signal over neural ion channels in the brain can range from .19 Hz - 30 Hz at low voltage. For an interference example, AC electricity is 60 Hz at high voltage and ...
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The role of PCA (Principal Component Analysis) in recording neurons
I am reviewing the recording methods from an experiment that tracked neuronal activity on the prefrontal cortex of a monkey.
From the method description in Nieder, Andreas, David J. Freedman, and Earl ...
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Issues obtaining Fo in DIY Imaging Fluorometer
I have successfully built an imaging fluorometer at home (see project details here) and so far is working amazingly well.
But I am having serious issues in obtaining Fo to calculate Fv/Fm (Fm-Fo)/Fm. ...
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Are neurons capable of buffering a signal to sync up with other data?
The brain is the most complex thing that mankind discovered thus far in the universe. Super computers aren't able yet to outperform the human brain (running only on ~25 watt or so) on the domain of ...
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Is this an ectopic beat? [closed]
First of all, I am unclear as to whether the answer to this question is a matter of fact or of opinion.
Nevertheless, I hope to find the answer.
In the image below, is the green beat considered ...
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Phase Shift in Grid Cells
I would like to fully understand the phase shift in the grid cell in MEC. From my understanding, since there is a hexagonal (i.e. equilateral triangle) lattice, and hence there are 3 $\phi$'s, I have ...
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Why don't we hear ultrasonic sounds as aliased versions of the original signals?
The upper limit of hearing is approximately 15 kHz, dependent on age and other factors. According to the principles of digital signal-processing, such an upper limit would mean that the auditory ...
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Hand motor control of the brain [closed]
I was watching a documentary (don't remember the name or the URL to the documentary) but they stated that the brain is layered and that each new layer is placed on top of the last. So the most ...
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Long-Term EMG studies
I am having trouble differentiating onset/offset of muscle activation. Is there anyone in the field has a specific way to set the threshold for both time and magnitude?
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Understanding the configuration of channels in the 10-20 EEG montage
In a typical 10-20 system there are 21 electrodes placed on the scalp. However, this does not mean there are 21 distinct "channels" or voltage sources.
I've heard that some of these electrodes are "...
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What signal processors comprise an Event-Related Potential system for EEG?
So my 30,000 ft. understanding of the EEG signal processing data flow is:
Capture raw EEG data ("raw waveforms")
Run these raw waveforms through a Signal Processing Framework that consists of 1+ "...
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Why is Fast Fourier Transform applied to raw EEG data?
I am trying to understand why Fast Fourier Transform (FFT) is used in the analysis of raw EEG channel data.
My understanding (at the 30,000 ft view) is that FFT decomposes linear differential ...
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Analysing the ERP (Event-Related Potential from EEG recordings) in terms of the P-300 wave
I am trying to understand how to analyze ERP (Event-Related Potentials) from EEG recordings in focus on P-300 waves.
I have come up with a few questions which I hope you might be able to help with:
...
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Why are local field potentials generally band-pass filtered?
I was wondering what the rationale was behind low-pass or band-pass filtering in local field potential measurements?
It seems to me that we could potentially filter out potentially valuable ...
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Pearson correlation of neural responses with it's linear estimation
I am trying to anderstand the following fact from this article (page 13):
How can single neurons predict behavior
Suppose I have a linear estimation of a stimulus:
$ \hat{s} = \mathbf{w}^T(\mathbf{r} ...
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Electrocardiogram: Difference between Atrial Fibrillation and Atrial Flutter
I have been working on analyzing Electrocardiogram data.
I have read several documents related to conditions of the Atria during fibrillation and flutter, the most lucid being that atria quiver with ...
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Do repetitive movements on EEGs show up as discernible patterns?
Here is a typical EEG reading:
(source: frontalcortex.com)
If I am connected to an EEG, and am sitting perfectly still, and then begin doing some repetitive motion, say, 10,000 times, will we see ...
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What are wave frequencies in the EEG?
Here is a typical EEG reading:
(source: frontalcortex.com)
I understand that each row corresponds to the signal read between two sensors on a standard 10-20 (or 10-5) distribution setup (e.g. ...
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Electrocardiogram: Missed beats in presence of Ectopic beats or Premature Atrial/Ventricular Contraction beats
I have been working on analyzing Electrocardiogram data.
So far, i have identified Ectopic beats and Premature Atrial/Ventricular Contraction beats.
I am working on identifying Missed Beat in the ...
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What are the highest and lowest amplitude values in ECG for humans?
I'm currently trying to parse the records captured from an ECG device and display them on a mobile application. I am wondering what the highest and lowest possible amplitude values for ECGs are in ...
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What physical or mental actions can be picked up by EEGs?
There certainly seem to be a lot of gadgets and gizmos leveraging EEG technologies to the control of devices.
This makes me wonder: what intentions/thoughts can be captured by EEG technology, and ...
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Possible to remove accumulated haze on fluorescence interference filters?
I have a few different fluorescent microscopes, the two that use Mercury lamps are older than 7 years. I notice on those that the thin film filters in the filter cubes (green, red, blue) have ...
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Criteria for compound action potential thresholds
As opposed to action potential thresholds (which are binary yes/no events), electrophysiological thresholds of compound action potentials are arbitrary. Mostly a certain noise level is picked and when ...
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What is the difference between rheobase and threshold?
Neuronal tissues can be excited by electrical stimulation. Two commonly encountered characteristics for electrically stimulating nerve cells is the threshold and the rheobase. My question is what the ...
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To determine no beating cardiomyocytes from ECG or video recording
I am trying to find data and some method by which I can see and say that there are some cardiomyocytes not working.
I have reviewed many arrythmia data where I think I can see much cardiomyocetes ...
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