Review / ERP

DATA REVIEW AND PROCESSING MODULE

This main BESA window provides many tools for reviewing and processing of your EEG or MEG data. Raw data are directly read using readers implemented for many EEG and MEG file formats. Data processing steps include digital filtering, artifact detection and correction, computation of correlation and spectral analysis. All these steps can be performed easily with a few mouse clicks. A variety of different display options allows for convenient review of your data.

Data import and export

• Direct readers for most EEG and MEG data file formats
• Import of user-defined file formats using generic reader
• Data import / export to ASCII and binary formats, e.g. MATLAB

Data processing

• Superior digital filtering: high, low, and narrow band pass, notch
• Interpolation from recorded to virtual and source channels
• Automated EOG and EKG artifact detection and correction
• Advanced user defined instantaneous artifact correction
• Pattern detection and averaging by spatio-temporal correlation

Data review

• Easy and fast review of digital EEG and MEG data files
• Fast paging, tagging and selected viewing of epochs of interest
• DSA and event displays for quick jump to relevant pages
• Additional selected and virtual artifact channels (EOG etc.)
• Linear and non-linear correlation between scalp and source channels
• Spectral analysis: FFT, DSA, power and phase mapping

ERP ANALYSIS AND AVERAGING

This module assists in extracting event-related potentials or fields from your raw data. It provides an easy-to use interactive tool for designing your own scripted paradigms with predefined trigger definitions, conditions and settings for averaging. Data Files can be scanned automatically for artifacts, and bad channels and samples can be easily identified and excluded using an advanced 2D selection tool. A variety of displays is at hand to view the event-related signals, including 3D whole head maps and event-related (de)synchronization

Handling of paradigms, events, and conditions

• Scripted paradigms for fast definition of triggers, conditions, epochs, filter settings etc.
• Import, export, and editing of event lists, triggers, and paradigms
• Design of complex conditions by logical expressions
• Creation of triggers from recorded signals, e.g. rectified EMG

Batch scripts for automated processing

• Fast and automated analysis of group studies using batch scripts
• Script functions for paradigm import
• Automated artifact scan with 2D graphical rejection tool
• Batch guided averaging within and across subjects
• User-defined combination of conditions (e.g. difference, average)
• Automated ERP peak detection and latency / apmlitude output
• Spatial and temporal data interpolation
• Batch commands for most source analysis functions

ERP displays and tools

• Topographic display and 3D whole-head mapping of averaged waveforms
• User definable layout with postscript export
• Overplot of multiple conditions
• Display of additional channels (polygraphic,intracranial, source, EEG, MEG)
• Event related (de)synchronisation: Display of ERD/ERS waveforms