Some information regarding edf file

[kumar Raj]

Hi, in the manual, I can see the following information
CQ_AF3…CQ_AF4
These numbers show the color of the CQ Map indicators, where 0=BLACK, 1 =RED, 2=ORANGE, 3=YELLOW, 4=GREEN.

I have doubts
1. does BLACK or ZERO(0) mean that a particular electrode is not receiving data as it is not properly adjusted or not working

for example, CQ_T7 is always zero (black), what does it mean?

[luckham jerill]

Thank you for your question.

Contact Quality (CQ) is an impedance measurement that indicates the quality of the electrical signal passing through the sensors and the reference. It can be one of 4 values: 0 – very bad (black), 1 – bad (red), 2 – ok (orange) and 4 – good (green). If you have black sensors, it means the electrodes are not pickup electrical signals as it is not properly adjusted or very noisy. (https://emotiv.gitbook.io/cortex-manual/setting_up_your_eeg_device/view_contact_quality_map/contact-quality-cq-vs.-eeg-quality-eq)

If you have other questions, please let us know.

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