An electronic system (1) for monitoring eye activity of a subject, comprising: a plurality of EOG electrodes (103,A,B,C,D,REF)； electrode circuitry (104) configured for measuring an adapt EOG signals received from the plurality of electrodes (103,A,B,C,D,REF)； and a data processing unit (106) configured for performing EOG signal processing and eye activity determination； wherein the data processing unit (106) is configured for performing eye activity determination based on at least a first diagonal eye biosignal vector (Diagonal 1) derived from the biosignals measured between at least a first electrode pair (B,C) that, in operation, is located on a first diagonal plane (D1) around a subject's eye. A wearable device (100,200) and a method for monitoring eye activity of a subject.
