For those who make high-end EEG recordings using BRAIN PRODUCTS equipment and want to include video-based observations in your study.
In this example, we describe the integration of the BRAIN PRODUCTS Recorder, BRAIN PRODUCTS Analyzer in your Mangold Video Lab, Mangold DataView, and Mangold INTERACT, either with or without making use of a stimulus presenter during your session.
The integration allows you to watch the scenes in the video(s) that match the sequences of specific stimuli.
Additionally, we can transfer video-based behavioral data to the BRAIN PRODUCTS Analyzer so that you can make use of the high-end specific EEG/ERP analysis routines for the sequences observed and logged as Events in INTERACT.
Mangold Video Lab Setup
A BRAIN PRODUCTS setup includes several hardware boxes to record EEG and to present stimulus information.
The scene itself is recorded within a Mangold Video Lab setup, using Axis IP cameras and VideoSyncPro Studio.
VideoSyncPro Studio co-ordinates the recording of all audio and video material and sends a synchronization signal to your BRAIN PRODUCTS device the moment you start a recording.
A stimulus presenter is connected to this setup as well.
The picture shows you how to connect your Brain Products system with our VideoSyncPro Studio recording system:
Note: More cable configuration details are available in a separate 'Mangold to Brain Products Trigger' document you can ask for if you have trouble with the implementation.
Cable Specification Brain Amp EEG Amplifier
The BrainAmp EEG amplifier has only one LPT input (more precisely: the BrainAmp system has an LPT cable that leads into the Brain Products USB2 adapter box, to which the EEG amplifier is also connected via fiber optic cable).
The BrainAmp system has an additional pin on the LPT cable that ends in a BNC socket.
Thus, a Mangold LPT cable with all data pins connected to a BNC connector enables us to send the trigger using this additional pin.
All you need to do is configure the digital port settings in the Brain Products Recorder Software to retrieve this information and label it, for example, 'Mangold Video Start - Stop'. Details can be found in the Brain Products documentation.
Cable Specification actiCHamp EEG Amplifier
The BrainProducts actiCHamp amplifier has only an 8-bit input (i.e., no extra signal inputs).
Here we need the Brain Products TriggerBox (an LPT signal merger box) to be able to send trigger signals from two devices to the actiCHamp amplifier.
Synching Process
The moment the video recording has started, a marker signal is send to the BRAIN PRODUCTS Recorder, which is written into a dedicated marker file (*.vmrk)1. Only after the video recording is started, the stimulus presenter comes into action, also writing a marker signal into the marker file of your BRAIN PRODUCTS session.
1) If you have old Marker files that are named *.amrk you can rename these files to get it to work.
Syncing Signals
Communication from third-party systems with the BRAIN PRODUCTS device is only possible through an LTP-signal. Therefore we insert a PCI card with LTP-socket and connect a corresponding cable between the VideoSyncPro IP recording station and the BRAIN PRODUCTS Recorder.
To set up the communication, all you need to do is activate the LTP-trigger signal in the Mangold VideoSyncPro Studio settings dialog:
▪Activate all three Send trigger... options
▪Enter the decimal LPT-Port address used for the card in your computer (If you have a hexadecimal value, convert it to decimal first).
▪Activate the required pin for the synching-signal.
For a typical Brain Products setup only Pin 9 should be used because the EEG stimuli use the other pins.
▪For Brain Product connections, a trigger duration of 10 milliseconds at the start of a recording is sufficient.
Depending on the configuration of the Digital Port settings in the BP-Recorder, you may also use the 'always high' option to create an active signal during the whole recording.
Note: The Trigger Duration enables you to ensure that the receiver can actually receive the signal (and it does not accidentally fall into the gap between two samples when the sampling rate is low). Because the sampling rate for the BP-Recorder is very high, even a s2-3 milliseconds signal would be long enough.
Our signal is stored as a Marker entry in the BRAIN PRODUCTS specific Marker file.
IMPORTANT: You need to start the BRAIN PRODUCTS-based recording BEFORE your start the video recording in Mangold VideoSyncPro Studio.
If you make use of a stimulus presenter, the presentation should only start AFTER the Mangold VideoSyncPro Studio recording has started.
Note: For synchronized playback of BP-values a your video recordings, you need Mangold INTERACT and Mangold DataView. How to tranfer the data is described in the documentation of DataView.