What function do eye leads primarily serve in EEG monitoring?

Eye leads in electroencephalography (EEG) monitoring are primarily used for tracking eye movements. This function is essential as the movement of the eyes can create artifacts in the EEG signals that might obscure the underlying brain activity. By placing electrodes in appropriate positions near the eyes, clinicians can identify and account for these artifacts during the analysis of EEG data. Understanding the correlation between eye movements and EEG signals allows for accurate interpretation of the recordings, enhancing the quality of diagnostic information.

The other choices do not align with the specific purpose of eye leads. Monitoring heart rate is done through cardiovascular assessment techniques, measuring muscle tension relates to electromyography, and detecting environmental noises is not a function served by eye leads but rather involves sound recording equipment or filtering during signal acquisition.