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== Signaltransmission to the EEG ==

Once the bioelectric current is transduced at the surface of the electrode, the electric current travels along the path of least resistance to the EEG amplifier. In most cases, this transmission of the EEG signal occurs along conductive wiring leading from sensing electrodes to the circuitry of the amplifier. Lead wiring is typically con-structed of a highly conductive material and is typically both insulated and shield-ed. Insulation of lead wires typically takes the form of a protective jacket surround-ing the wire, which has very high resistance to the flow of electric charge, simply preventing the transmission of charge in one lead wire from influencing the signal in neighboring leads. The shielding of lead wires reduces the extent to which elec-trical noise in the environment interferes with the transmission of the EEG signal. The importance of protecting lead wires from electrical noise cannot be underestimated, because virtually all of the electrical noise in EEG recordings is introduced in the lead wires between the electrodes and the amplifier.