Physiological measurement systems

While you are collecting observational data, you can simultaneously acquire physiological data, such as EEG, ECG, EMG, blood pressure, or skin conductance, with an external data acquisition system. Although you can add your own system, Noldus also offers several data acquisition systems that work in conjunction with The Observer® XT. You can benefit from synchronous recordings of physiological data, video, and behavior.

Record all your data in sync with just one push of a button.

Latest release - what's new?

In the latest release of The Observer XT, the ideal data integration platform, several improvements were made for easy and accurate data integration and communication between the different software and hardware.

BIOPAC AcqKnowledge integration

Control of physiological data acquisition with a BIOPAC system has improved. Communication between BIOPAC AcqKnowledge and The Observer XT now makes use of the Noldus network communication protocol N-Linx. This simplifies start and stop of physiological data acquisition and synchronization with the Event Log in The Observer XT.

Physiological data collection

Tobii Pro Studio integration

Next to physiology, researchers often also collect eye tracking data. Communication between Tobii Pro Studio and The Observer XT now also makes use of the Noldus communication protocol N-Linx. This simplifies start and stop of the eye tracking recording and synchronization with the Event Log in The Observer XT.

Tobii Pro Noldus
Eye tracking technology for research

Improved FaceReader integration

Emotion analysis is often included in a lab set up. FaceReader videos can now automatically be linked to a live observation in The Observer XT and synchronized with the events. Also, multiple FaceReader instances can be controlled with one instance of The Observer XT. In addition to this, FaceReader allows you to import analyses of multiple persons into one observation in The Observer XT. This is useful if you are interested in the interaction between test participants.

Facial expression analysis

E-Prime Studio 3.0 support

A new version of the E-Prime client and server are released with The Observer XT 14.1, so that it supports E-Prime Studio 3.0.

Customer testimonial

“The integration of FaceReader, the Observer XT, and psychophysiological data collection make research programs possible at locations and within timetables that increase opportunity, quality, and efficiency.”

Dr. C. Barton | Davidson College, USA


  • Take advantage of fully integrated set-up.
  • Easily and accurately synchronize physiological responses with behavioral coding.
  • Measure the internal state of your test participant.
  • Collect ECG, EEG, skin conductance, respiration, and more.
  • Study the interplay of external events, physiology, and behavior.
Learn more about psychophysiology!


Although your test participant may appear to be calm, he or she may be concealing a considerable amount of stress. To reveal this level of stress, you can combine behavioral coding with physiological measurements acquired with a data acquisition system. For example, skin conductance is a method of measuring the electrical conductance of the skin which is used as an indication of psychological or physiological arousal.

A combination of physiological and behavioral data can provide you with essential information that will help you to further understand and explain your participants’ behaviors. In some cases, you might find that your test participant is tense due to environmental variables, such as the behavior of another person, or the difficulties that the software presents the test participant with. The key understanding these processes is precise integration. Therefore, Noldus can support you in measuring:

  • heart rate
  • skin resistance
  • skin temperature
  • muscle tension (EMG)
  • neuronal activity (EEG)
  • and much more!

Multimodal research

Data acquisition systems enable you to study almost any research topic involving emotions, or mental and physical load. We help you build the right solution, consisting of a data acquisition system and The Observer XT, the ideal platform for multimodal research.

The data acquisition system can be started from The Observer XT giving you just one starting point. Furthermore, The Observer XT will automatically send out a synchronization signal to the data acquisition system, making sure your external data is in sync with your video recording. And to make the solution complete, The Observer XT External Data Module has predefined import profiles for the acquired data.

In the Observer XT software you can easily link external data such as heart rate measurements to a specific observation. This allows you to select interesting episodes, for example nesting intervals when the heart rate was between 80 and 100 beats-per-minute. You can visualize your physiological data together with the event data and video in the observation. And, you can calculate statistics in The Observer XT. It allows you to analyze physiological data based on the selection you made. Finally, you can make charts in order to present your analysis results to your colleagues.

The Observer XT and E-Prime

E-Prime from Psychology Software Tools is a stimulus presentation program widely used in psychological research. The combination of The Observer XT and E-Prime provides insight in the relationship between behavior and presented stimulus. If you want to use The Observer XT in combination with for example FaceReader, an eye tracker, E-Prime and physiological data, this integrated solution is perfect for you! After the experiment the data from E-prime is automatically transferred to the Observer XT and all actions are synchronized on one time-line in The Observer XT.

Customer testimonial

“I would buy the Observer XT software again. It saved me months of time.”

Dr. E. Eadie | University of New Mexico, USA

High-quality equipment

Since The Observer XT is set up to work with a broad range of equipment from several suppliers, we can offer a wide range of data acquisition devices, including:

  • Stationary and wireless data acquisition base units, consisting of:
  • ECG module (heart activity)
  • EEG module (brain activity)
  • EMG module (muscle activity)
  • EOG module (horizontal eye movements)
  • GSR module (transpiration)
  • Respiration module (VO2 and Respiration Exchange Ratio)
  • Oxygen saturation module (non-invasive)
  • Heart beat module (non-invasive)
  • Blood pressure module (non-invasive)
  • Portable heart rate monitor

Of course external data use in The Observer XT is not limited to physiological signals. You can also integrate data such as steering wheel pressure, pressure plate output, location specific data, (water) temperature data, etc.

Preferred suppliers

We only work with world-class suppliers. Our preferred suppliers for data acquisition devices are:

  • Biopac Systems, Inc.
  • Mindware Technologies
  • Polar Electric

Selected custom integrations

The Observer XT has previously also been integrated with:

  • ADInstruments
  • Becker Meditec
  • Biosemi
  • EGI
  • TMS International
  • VU-AMS
  • G-tec

Note: other brands and types of data acquisition equipment can be delivered or integrated as custom solutions. See the consultancy section or contact your sales representative today!

Contact us

Please contact our sales department if you have any questions or if you are looking for technical specifications. As technology rapidly advances, we are more than happy to provide you with the most up-to-date information.

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