A cortical sensing device for contact with the surface of the brain is provided that includes a support member, at least one macroelectrode sensing element secured with respect to the support member and at least one microelectrode sensing element secured with respect to the macroelectrode. The support member is substantially thin and made from flexibly-conformable material to accurately and safely place the sensing device upon the brain surface. The microelectrode sensing element is surrounded by the macroelectrode brain-contact surface of the macroelectrode sensing element. The first surface of the support member, the macroelectrode brain-contact surface and the microelectrode brain-contact surface are substantially co-planar to abut the surface of the brain for sensoring and monitoring.