A sensor array apparatus for monitoring medical signals includes a
flexible substrate adapted to generally conform to a topography of a skin
surface. The flexible substrate includes a central portion arranged about
a central focal point and a plurality of finger-like projections
extending radially outwardly from the central portion. At least one
reference electrode is disposed on the central portion of the flexible
substrate. A medical electrode is disposed on at least one of the
finger-like projections, preferably, each of the finger-like projections.
Connector, in electrical communication with the medical electrode, is
adapted to connect to an electronic system. The flexible substrate
defines at least two reference apertures for accommodating a body
structure. The apertures permit the conductor to interface with the
electrical system from either side of patient tissue.