E-prime Mark

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LinDN
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E-prime Mark

Post by LinDN »

I was using e-prime to conduct PVT psychological experiments and using MM to record EEG data. I wonder if MM provides ports that allow eprime to send triggers for marking. Or is there another way to align muse EEG tags with experimental stimuli in time so that the required EEG fragments can be correctly captured?
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James
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Re: E-prime Mark

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Recorded and streamed data from Mind Monitor has a timestamp on it, so provided your computers are in sync (which pretty much all are these days automatically), then you can use that.
One thing to note is the data from the Muse device has to go through the bluetooth packet buffer in the phone, and it's only after that that timestamps are applied, so you will see some clumping in the timestamps due to the bluetooth packets getting processed in chunks.
If you want to go the hardware route you could always hook something up to send a pulse through the AUX electrode pin on the USB port, then you'd have that spike in the data to look at.
LinDN
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Re: E-prime Mark

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James wrote: Mon Aug 07, 2023 12:46 am Recorded and streamed data from Mind Monitor has a timestamp on it, so provided your computers are in sync (which pretty much all are these days automatically), then you can use that.
One thing to note is the data from the Muse device has to go through the bluetooth packet buffer in the phone, and it's only after that that timestamps are applied, so you will see some clumping in the timestamps due to the bluetooth packets getting processed in chunks.
If you want to go the hardware route you could always hook something up to send a pulse through the AUX electrode pin on the USB port, then you'd have that spike in the data to look at.
At first, I also wanted to find the time stamp manually to align, but I found that the output result of E-prime only recorded the exact time of the start of the experiment and the time of the stimulus interval, and did not give the exact time stamp of each stimulus point. This is where it gets messy. Does ‘the AUX electrode pin on the USB port’ you mentioned require additional hardware purchase? (by the way I used muse S)
LinDN
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Re: E-prime Mark

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LinDN wrote: Mon Aug 07, 2023 2:49 am
James wrote: Mon Aug 07, 2023 12:46 am Recorded and streamed data from Mind Monitor has a timestamp on it, so provided your computers are in sync (which pretty much all are these days automatically), then you can use that.
One thing to note is the data from the Muse device has to go through the bluetooth packet buffer in the phone, and it's only after that that timestamps are applied, so you will see some clumping in the timestamps due to the bluetooth packets getting processed in chunks.
If you want to go the hardware route you could always hook something up to send a pulse through the AUX electrode pin on the USB port, then you'd have that spike in the data to look at.
At first, I also wanted to find the time stamp manually to align, but I found that the output result of E-prime only recorded the exact time of the start of the experiment and the time of the stimulus interval, and did not give the exact time stamp of each stimulus point. This is where it gets messy. Does ‘the AUX electrode pin on the USB port’ you mentioned require additional hardware purchase? (by the way I used muse S)
If I use USB-TypeC to connect my laptop to my ipad(with MM installed), can I send a specific signal (a number on e-prime) through the USB port that causes the mind monitor to use its built-in mark button (1-5) to record the stimulation time while recording the EEG state? (Since I am completely new to communications, I am puzzled by this issue.)
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James
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Re: E-prime Mark

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You'd need extra hardware to send a signal pulse. Like an ESP8266 or similar.
LinDN
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Re: E-prime Mark

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Thanks ever so.
LinDN
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Re: E-prime Mark

Post by LinDN »

Sorry, I think I'm still a little confused.
E-prime can send the specified command signal through the Bluetooth serial port. But as far as I know, muse can't connect to the mind monitor using Bluetooth at the same time as connecting to a PC via a data cable. So E-prime's signal should not be sent to muse. Can the mind monitor accept the signal from the Bluetooth serial port through some control protocol and give feedback?
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James
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Re: E-prime Mark

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No, I'm saying it's possible to hard wire to the Muse USB port to inject signals into the AUX electrode.
But, it'd be much simpler to just write out your trigger timestamps and compare them against the ones from Mind Monitors recorded/streamed data.
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