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10

There is no better way to describe brain activity than brain waves! :) There are newer ways to analyze and think about brain waves, though. Usually you will find these under literature on neuronal oscillations. Good aspects of thinking about brain activity using brain waves: Brain waves are directly related to neural activity. They are an electric or ...


10

Yes and no. Source estimation has been utilized in electrical engineering for decades, but is becoming more and more prevalent in the EEG realm, especially in light of efforts to register EEG readings with concurrent fMRI studies. Basically, given a set of EEG (or even MEG, magnetoencephalographic) measurements, can we "invert" them to find the individual ...


7

Programs/packages for EEG analysis There are decent MatLab toolboxes with good tutorials for for the analysis of EEG data. The EEGLAB toolbox (tutorial) can be operated by both GUI and command-line (and script). The fieldtrip toolbox (tutorial) is mainly operated by command line / script. Of course there are also (commercial) software packages for EEG ...


7

As often in this area, the problem seems to be entirely created by confusions about definitions and terminology and the difficulties resulting from the use of common-sense concepts like “surprise” in scientific theories. One answer would be “Why not?” Basically you seem to object to the definition of surprise used by some theorists but definitions are ...


6

I use the FieldTrip toolbox in Matlab to analyze my own modified auditory MMN experiment :) But I use MEG, so I don't have that many software options. The toolbox is very powerful but it has a steep learning curve and I would recommend it only if you already have both Matlab and EEG data analysis experience. I don't analyze my data in the classical MMN way ...


6

Antoine Tremblay has just released an advanced analysis toolbox: http://onlinelibrary.wiley.com/doi/10.1111/psyp.12299/abstract It's missing about half the features on your list, although fundamentally, spectral density is a simple task and LORETA is a stand-alone package anyways (although similar approaches, e.g. general CSD estimation, are implemented in ...


6

This very much depends on what, exactly, you're trying to do. EEG measurements tend to be extremely reliable, but the inferences one may draw on mental state are not necessarily so. EEG-driven BCI overwhelmingly relies on machine learning to correctly classify signals into a finite number of categories and act upon them. Typically, you'll do something ...


5

Also. Appraisal theory argues that a cognitive mechanism assesses the meaning of a situation before initiating an emotion. It does not argue that this mechanism operates consciously, so demonstrating that it doesn't doesn't impinge on the validity of appraisal theory at all. Mismatch negativity may be part of the process leading to surprise, but noting ...


5

I'm surprised that no one has mentioned spiking activity. The spatial and temporal resolutions are phenomenal. The technology to record action potentials simultaneously from many neurons over many cortical areas is growing. Much of theoretical neuroscience deals with how those patterns of spiking convey information. As with the other answers, I will add ...


5

How many trials do you have per condition? With a small number of trials in the deviant condition, and a small number of participants, these things can happen. The ISI would not cause this per se, however, have you considered looking at effects of the previous trial? You can analyze the baseline intervals as a function of what type the previous trial was, ...


5

Steven J. Luck's "An Introduction to the Event-Related Potential Technique" is a great beginner's book on EEG. It's basic but not too simple, and it goes into the structure of the signals as well as into issues on experimental design.


5

Disclaimer: These are my preferences, biased by my own research experience. In general, I am not a fan of block designs. Blocking introduces difficulty in comparing both neural and behavioural activity between blocks due to effects of practice, fatigue, adaptation, learning, boredom, muscle tension and possibly others. It is of course possible to ...


5

Yes, and no. Biofeedback has been an active field of research since the 70s, but has been a bit "fringified" as a cure for ADHD, etc. It is possible to fine tune the brain activity for specific tasks. To borrow an example from BCI, the Rolandic Mu Rhythm can be used to "train" a user to refine the movement of a cursor or other pointing device. Jonathan ...


4

Michelle Heijblom's (2009) master thesis on Visualising tinnitus with fMRI and EEG mentions the following: Different studies report that tinnitus is characterised by an increase in slow-wave activity (0.5- 4Hz: delta activity) and a decrease in alpha activity (8-12 Hz) at temporal regions. Recently it has been suggested that this loss of alpha ...


4

http://sccn.ucsd.edu/eeglab/ http://chronux.org are two libraries with tons of functions for analyzing eeg and emg data


4

I've used the Zeo (http://www.myzeo.com/sleep/). It seems to work pretty well. It tracks which stage of sleep you are using a very basic EEG. There are some details on how it operates here: http://radar.oreilly.com/2009/10/how-the-zeo-sleep-device-works.html As I said, I've used it in the past and from what I can tell, it seems to be pretty accurate, ...


4

Do you mean evoked potentials, or event-related potentials, or just straight-up EEG? The general way to distinguish between the two is that EEG will tell you about state (aroused, asleep, etc) where evoked or event-related potentials will tell you about operations (processing sound/language/etc); evoked or event-related potentials also generally require ...


4

We were looking for an EEG device few years ago. The commercial offers were between 20,000 EUR for a 32 passive electrode to 50,000 EUR for an 64/128 active electrode. This included everything except the computers - some offers were without off-line data processing software. I never considered the EEG systems that were not mentioned in the method section of ...


4

Point by point: The Melon headband has three electrodes. Our primary electrode is on the forehead region known as FP1, where Melon can monitor brainwave activity from the prefrontal cortex. The problem with this is that electricity doesn't work like that. Current always flows between two points, and our electrodes measure the potential between two ...


3

You can't. Flatline EEG is how brain death is defined, and while it may be possible to induce an eye blink in a deceased human, I am sure ethics will not approve, and it won't be scientifically satisfactory. even in the case of a real flatline EEG, there will always be some remaining residual activity (albeit very weak), such as line noise. However, ...


3

If I understand your question correctly, yes, since ERP involves averaging over similar events, very accurate time-locking to stimulus onset is critical. The idea of an ERP is that activity relevant to the stimulus will happen at a similar timepoint after similar stimuli--if you don't have an accurate time stamp (usually to the level of single milliseconds ...


3

As far as I know, short answer is no - there is no gold standard for EEG files. But EEG is a time series (amplitude) from several channels. So the most common way to represent it is columns as electrodes and rows as points of time. I think almost all software is possible to read such structure as txt file. But EEG is not only time series. Usually it is ...


3

Bearing in mind the fact that I can't prove a negative, I'm going to say "No, it's not (yet) possible". Flow is rather loosely defined (e.g. "merging of action and awareness"), so coming up with hard measures is a challenge in and of itself -- even without bringing electrophysiology into the equasion. As a Positive Psychology concept, it belongs to the ...


3

The gold standard of sleep studies is polysomnography- using multiple sensors together to score sleep stages. It's very expensive and requires a lab. A night in a sleep lab costs about 3000$, last time I checked. Actigraphy is a cheaper way of monitoring sleep by looking at the users motion. When 19 out of 20 minutes are scored as "no activity", the first ...


3

MEGs using SQUIDs can detect magnetic flux density measured in teslas. Away from sleep studies and epileptic brain activity, this should be a useful indicator of relative brain arousal. Readings from two different people on this scale should be comparable based on the orders of magnitude for the unit measurement. As for comparative measurements of brain ...


3

Beyond what you've already listed, you'll need advanced signal processing skills, as so far, nobody has figured out how to get much more meaningful information out of the EEG than broad attentional state (alpha blocking and the P300, and the evoked potentials), and maybe some correlates of motor imagery, though none of these have realistically proved ...


3

The steady state response is a sustained oscillatory response to a stimulus that is varying in strength with some regularity. But it is not a true oscillation, it's closer to an ERP in nature: it is a stimulus-driven response to variations in the stimulation. In auditory processing, which I am familiar with, people take a tone and then add an amplitude ...



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