EEG Assessment and Brain Mapping

The EEG assessment, commonly referred to as a brain map, serves as an initial diagnostic tool to identify and define optimal training locations in accordance with the International 10-20 system. A widely used approach for EEG assessment is Quantitative Electroencephalography (qEEG), which extends beyond traditional visual EEG interpretation to provide a more detailed analysis of brain function.

qEEG involves multi-channel EEG recording, wherein raw digital EEG data is processed using advanced signal analysis algorithms. Classical methods include Fourier Transform analysis, while more contemporary techniques may utilize Wavelet Transform analysis for enhanced precision in capturing temporal and spectral EEG characteristics. The processed EEG data undergoes statistical analysis, often comparing the recorded values against established normative database references, such as NeuroGuide or comparable systems.

The results of this analysis are typically visualized through topographical brain maps, which provide a color-coded representation of brain activity patterns. These brain maps aid in identifying potential dysregulations, asymmetries, or deviations from normative values, thereby facilitating a more data-driven and personalized approach to neurofeedback training and cognitive performance optimization.

How is it measured ?

EEG is measured by placing electrodes on the scalp, typically following the International 10-20 system, to record electrical activity generated by the brain. These electrodes detect voltage fluctuations resulting from neuronal activity, capturing signals that reflect brainwave patterns across different frequency bands, such as delta, theta, alpha, beta, and gamma.

The signal acquisition process involves amplifying the raw EEG data to enhance signal clarity while minimizing artifacts from muscle movement, eye blinks, or environmental interference. NeXus systems can record EEG using 1 to 21 channels, allowing for targeted or comprehensive brain assessments. Data is then digitized and processed through various computational methods, including spectral analysis (e.g., Fourier or Wavelet transforms), to extract meaningful patterns.

For clinical and research applications, EEG data can be evaluated in real time or further analyzed through quantitative EEG (qEEG). This method applies statistical and comparative analysis, often utilizing normative databases to assess deviations from expected brain activity patterns. The processed data can then be used to guide interventions such as neurofeedback training, cognitive rehabilitation, or neurological assessments, providing valuable insights into brain function and plasticity.

Common EEG Assessment Measurement Setups

EEG assessments can be conducted using different channel configurations, depending on the level of detail required for analysis. The most common setups include:

• 1-Channel EEG: Used for targeted assessments or simple neurofeedback training, typically focusing on a specific brain region.
• 2-Channel EEG: Allows for basic bilateral comparisons or coherence training between two locations.
• 4-Channel EEG: Enables more comprehensive regional analysis while maintaining ease of use for neurofeedback applications.
• 21-Channel EEG: Provides full-brain assessments for advanced clinical diagnostics, research, and qEEG mapping.

NeXus EEG Systems & Benefits

• NeXus | 10 MKII – Supports up to 4-channel EEG, ideal for flexible, small-scale neurofeedback and assessments.
• NeXus | Q32 – Enables 21-channel EEG for full-brain qEEG mapping, suitable for advanced neurophysiological analysis.

Advantages of NeXus Systems:

✅ Real-Time Multi-Modal Integration – Simultaneously measure EEG alongside physiological signals like HRV, EMG, and skin conductance.
✅ High-Resolution Signal Processing – Ensures accurate, noise-free data acquisition.
✅ Scalability & Flexibility – Suitable for both targeted and full-brain assessments.
✅ User-Friendly Interface – Designed for efficient data visualization and interpretation.