Frequently Asked Questions

What do I need to use PEER?

PEER runs on any iPad or iPhone running iOS 10 or later. You will need an Apple ID in order to purchase the app. You will also need a MUSE headset from Interaxon (we recommend the 2016 model), and a computer (Mac or PC) to analyze your results.

Can I use the new MUSE 2 headband with PEER 2.0?

Yes, our application is fully compatible with the MUSE 2. However, please note that PEER does not record data from the new sensors that were introduced with the MUSE 2. It only records data from the sensors that are present on both the 2016 MUSE and MUSE 2.

On how many different devices can I use my copy of PEER?

When you purchase PEER, it will be associated with your Apple ID, rather than with any particular device. In general, you can use apps on more than one device as long as they share the same Apple ID, but we do not set the rules for multiple device usage. For more specific information on this topic, contact Apple.

Do you have any video tutorials on how to set up an experiment with PEER?

Here are some helpful video tutorials on that subject on the Krigolson Lab website.

In what format does PEER output its data?

PEER stores data in comma-separated values (CSV) files. It divides the data so that each sample has its own row, and the values for that sample are presented in the columns.

What's in the CSV file?

PEER gives you two options. The first is labelled "EEG & Markers," which is a minimal format that only includes the EEG data and the event markers. The second option is labelled "All." It includes all of the data recorded by the MUSE, such as gyro, accelerometer and artifact data.

How do I export my CSV file from PEER to my computer?

There are several options. You can email it, although you may experience difficulties if your email service can't handle large files. You can also transfer it via any file-sharing service that is installed on your iOS device, such as iCloud, Google Drive, or Dropbox. You can also transfer the file to a Mac via AirDrop. Here are the instructions for exporting:

  1. View a recording in PEER by tapping on it.
  2. Tap the "Share" button (upper right corner of the screen).
  3. Pick your export format from the resulting menu (e.g. Share CSV (All))
  4. The "Share" panel will appear. Pick the option you wish to use to transfer the file
    (e.g. Air Drop, Email, Save to Dropbox etc.)

What should I do with my CSV-format output file?

Many different programs can handle PEER’s CSV output. You should be able to choose whichever one works best for you. One prominent option is MATLAB. Many of our users like to use EEGLAB, which is a specialised toolbox for use with MATLAB.

I'm having trouble adapting my PEER data for use with EEGLAB. Can you help?

Yes! Our neuroscientists have written some MATLAB code that will convert PEER data into EEGLAB data. Click here to download a ZIP with the three necessary files. Note that you should apply this conversion only to the EEG channels and not to the full export.

How do I know what all of the event markers mean?

Here's a key that tells you:

Raw EEG recordings:


Gambling Task:

How do I know if PEER can do my experiment?

PEER is optimally suited to handle any experiment that fits within either the “Oddball” or “Go-No-Go” research paradigms. However, it also features a raw EEG data recorder that could potentially be used for almost any experiment that involves the collection of EEG data.

What if I want to use subjects who are colour blind?

PEER can be configured to use any selection of the colours in our palette, so you can avoid any colours that are problematic for your subjects.

How does PEER affect the battery life of my iPad/iPhone?

We recommend that you charge your device fully before use, as PEER will increase battery usage. A fully-charged device has enough power to complete many rounds of testing.

What about the MUSE battery?

In general, the battery for the MUSE will last longer than the battery for your iPhone or iPad. According to Interaxon, it should last for about five hours. However, we recommend that you charge it fully before beginning testing as well.

How much free space do I need to have on my device to store recordings?

PEER needs a significant amount of free space for data storage. We recommend that you have at least 100MB of free space per test subject.

What are the technical characteristics of the MUSE?

You can find a detailed listing of the MUSE headband’s technical characteristics at:

Where can I buy a MUSE?

For your convenience, we are happy to provide you with this direct link to help you get started on your purchase quickly. You can also buy headsets through major retailers such as Best Buy or Amazon, or directly from Interaxon.

How do we reach you if we have questions or concerns?

If your question is not covered by this list of FAQs, use our contact form to write us a message.