Which EEG lead configuration is commonly used for monitoring interhemispheric differences?

The bipolar montage is commonly utilized for monitoring interhemispheric differences because it records the electrical activity between pairs of electrodes. Each channel in a bipolar montage captures the potential difference between two electrodes placed on different locations of the scalp. This configuration is particularly effective for detecting asymmetries in brain activity, as it allows for direct comparisons between the activities of corresponding electrodes located on opposite sides of the head.

In situations where interhemispheric differences are significant, such as during certain pathological conditions or while studying functional lateralization, the bipolar montage provides clearer insights into how each hemisphere functions relative to the other. This is in contrast to other montages, which may not effectively highlight such differences.

For example, in a referential montage, recordings are made from multiple leads with respect to a single reference electrode, which may obscure localized differences in activity. Similarly, segmented montages typically focus on specific regions rather than the relationships between hemispheres, and single channel montages are limited to monitoring activity from one specific electrode, thereby missing broader interhemispheric contrasts. Thus, the bipolar montage is the preferred choice for effectively monitoring and analyzing interhemispheric differences in EEG readings.