Negative Electrode for Precordial Leads

[cannonball88]

I can't seem to find the answer to this.

ECG's reflect a positive deflection when the current is travelling toward the positive electrode (example: Lead II measures between RA and LL. When we acquire a 12-Lead ECG, the precordial leads are the positive electrodes. What serves as the negative electrode?

 

[dumbenoughtostay]

Look up Wilson's central terminal

 

[DesertMedic66]

Limb leads are bipolar leads, aside from the augmented leads, so they have a negative and a positive electrode. The precordial leads are unipolar which means there is no negative electrode.