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EDA: Electrodermal Activity


Wirelessly log or live view high-quality EDA data

Powerful, sophisticated acquisition and analysis algorithms.

Automatic EDA and Marking Routines

Measure the skin conductance level (SCL) and skin conductance response (SCR) as they vary with sweat gland (eccrine) activity due to stress, arousal or emotional excitement. Record wirelessly with BioNomadix® for both in lab applications and with the BioNomadix Logger to record data from participants at home, work and play,  or use wired EDA100C amplifiers in the lab or EDA100C-MRI in the MRI. AcqKnowledge® software includes a fully-automated electrodermal response scoring tool that locates skin conductance responses, visually identifies them on the waveform and extracts key measures. Automatic event related EDA analysis can also be performed by locating the onset of the discrete stimuli and identifying specific and nonspecific  SCR within a user specified time range. AcqKnowledge software can interface with multiple stimulus presentation programs including Superlab®, E-Prime®, DirectRT®, MediaLab®, Inquisit®, and Presentation®, plus Vizard® for virtual reality (VR). Use the new Focus Areas analysis tool for targeted EDA Analysis. Focus Areas allow the user to specify and mark areas of interest in the data and run automated analysis routines or the cycle detector specifically on the Focus Areas instead of the entire data file.

Try EDA tools in the free AcqKnowledge Demo

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Stimulus presentation and VR systems

Time synchronize stimuli to physiological data for event related applications that demand precision timing

Automated SCR Analysis

Accurately scores the SCR data and exports results to spreadsheet

View data in multiple formats

Extracted measures can be displayed as new channels in the recording, or exported to an Excel spreadsheet or Journal file for further analysis.

Application Starter Hardware  

Hardware Packages   |   EDA: Electrodermal Activity

Hardware Bundles are complete solutions for the specified application. Choose your preferred platform and bundle, then click "Request Pricing" to request an estimate, add/remove items, or complete purchase. If you have questions about specific items, click through to the product web page for details and specifications, or contact your Local Sales contact.





SCR data

Electrodermal Response Signal Processing

For basic EDA processing, take advantage of numerous filters, tools, and Automated Analysis routines in AcqKnowledge.Mark Onset, Peak, and End of SCRs on the Waveform

  • Derive Phasic EDA from Tonic
  • Event-Related EDA Analysis
  • Locate Skin Conductance Responses
  • MRI Artifact Removal

Derive phasic EDA from tonic EDA

This transformation uses baseline smoothing or high pass filtering to construct a new Phasic EDA channel in the graph. This routine is automatically included in both the locate SCR and Event-related EDA routines.

Spontaneous EDA Analysis

For studies requiring the examination of spontaneously occurring skin conductance responses, such as social paradigms, cognitive tasks, and arousal studies, use the Locate SCR routine in AcqKnowledge to locate and score spontaneously occurring responses. Run the Event Related EDA Analysis and the software will provide a frequency analysis over a user defined time period, between events in the data, or over a user selected region of data.

Locate Skin Conductance Response

Locate SCRs analysis will identify skin conductance responses and visually score the waveform. All SCR events are marked on the tonic waveform. In the SCR location mode the software marks the event onset, SCR point of max response, and waveform end. Responses can also be manually adjusted using the event marking tools.

Event Related EDA Analysis

AcqKnowledge EDA analysis dialog

For determination and correlation of EDA responses tied to a particular controlled discrete stimulus (visual cue, tone, image, mechanical stimulation, light flash, etc.) AcqKnowledge offers a fully-automated event-related EDA analysis routine. The routine scores and reports the data in two steps.

First, discrete stimuli marked by TTL pulses or via manual insertion  are converted into AcqKnowledge events by the digital input to stim events feature. The Digital input to stim events function works with TTL trigger information coming from applications such as Superlab®, E-Prime®, DirectRT®, MediaLab®, Inquisit®, Vizard®, and Presentation® and converts TTL data acquired on the digital channels of an MP device into useable stimulus events.

Next, stimulus events are marked as they occur in the data and AcqKnowledge automatically measures, or averages the response to the stimulus. To determine whether stimulus responses are specific (SSCR) or nonspecific (NSSCR), users can specify a time window around the stimulus event for measuring the data. Results can be pasted to a Journal file or automatically exported to a spreadsheet.

The results of the analysis are broken down into four parts and follow the guidelines set forth in the Handbook of Psychophysiology.

AcqKnowledge SCR EDA analysis results

  1. Event Related SCR data: Includes Specific SCR (SSCR) responses that fall within the defined time window after a discrete stimulus. Measures output include:
    • Stimulus Delivery Time
    • Skin Conductance Level
    • Response latency
    • SCR Amplitude
    • SCR rise time
    • SCR Size
    • SCR Onset
    • Stimulus Type
  2. Unmatched Stimulus Event Summary: Includes all discrete stimulus events that were not matched with a valid SCR response. The table displays event time and stimulus type.
  3. SCR Frequency Analysis: Includes each stimulus type, the frequency of specific and nonspecific responses along with the predefined epoch width.
  4. Stimulus Matching Summary: Includes the amplitude, magnitude, total number of matched, total number of non-matched, and frequency percentages for each stimulus type.

Advanced Features Spotlight

Electrodermal Activity (EDA) Scoring

Record and analyze EDA/GSR data wirelessly with BioNomadix or with standard wired amplifiers. AcqKnowledge includes a fully automated scoring system for electrodermal activity (EDA) data. More...

Event-Related EDA Analysis

AcqKnowledge® includes a fully-automated suite of tools for Event Related Electrodermal Activity applications. The analysis is based around the timing marks that come from stimulus More...

AcqKnowledge digital stim to events feature

Stimulus Presentation Event Marking

AcqKnowledge® includes a fully automated event driven data reduction program for Event Related Potential and other stimulus-response (S-R) applications. The feature comprises of two tools: More...

SCR data

Locate SCR

For studies requiring the examination of spontaneously occurring skin conductance responses, such as social paradigms, cognitive tasks, and arousal studies, use the Locate SCR routine More...

Skin Conductance Response Analysis

Skin Conductance Response (SCR) Analysis AcqKnowledge includes a fully automated skin conductance response (SCR) scoring system. The software will transform skin conductance level (SCL) data to More...



EDA Recording & Analysis Techniques



EDA - SCR Event Related Analysis

Focus Areas | AcqKnowledge Tutorial

Noldus The Observer XT Import/Export in AcqKnowledge

Poker Study | BioNomadix Wireless Data

EL-CHECK Electrode Impedance Checker


Spotlight On
free BIOPAC webinar

Evoked Potentials Part I: Exogenous and Stimulus-related Evoked Potentials

Learn how to use AcqKnowledge to stimulate and record responses.

You will learn about:
– Introduction to EPs
– Theory and guidelines
– How to record great EP data
– How to record exogenous EPs (BAEP, VEP, SEP)
– How to prepare data for analysis
– Analysis automation

Join Live Oct. 20 at 8am PT/ 11am ET

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