Cordance

Cordance is a statistical measure used in quantitative electroencephalography (QEEG) to assess the degree of synchrony between two signals. It is a measure of the consistency of phase difference between two signals, and is used in the analysis of brainwave patterns.

Overview

Cordance is a measure that combines both absolute and relative power measures from QEEG data. It was developed in the 1990s as a way to better understand the complex interactions between different regions of the brain. Cordance values are calculated by comparing the phase difference between two signals over time. This allows researchers to assess the degree of synchrony between different brain regions, which can provide insights into a variety of neurological conditions.

Calculation

The calculation of cordance involves several steps. First, the absolute and relative power of the two signals are calculated. The absolute power is the total power of the signal, while the relative power is the power of the signal relative to the total power of all signals. These two measures are then combined to create a cordance value. This value can range from 0 (no synchrony) to 1 (perfect synchrony).

Applications

Cordance has been used in a variety of research settings. It has been used to study the effects of meditation on brainwave patterns, to assess the impact of neurofeedback training on brain function, and to investigate the neurological basis of conditions such as depression and schizophrenia. It has also been used in the development of new treatments for these conditions.

Limitations

While cordance is a powerful tool for analyzing brainwave patterns, it does have some limitations. It is a complex measure that requires sophisticated statistical analysis, and it can be influenced by a variety of factors, including the quality of the EEG data and the specific methods used to calculate cordance values. Despite these limitations, cordance remains a valuable tool in the field of QEEG research.

See also

• Quantitative electroencephalography
• Brainwave
• Meditation
• Neurofeedback
• Depression
• Schizophrenia

Cordance Resources
Latest articles Most recent articles Ongoing trials	Wikipedia