Assessment of one of the sensory nervous systems of a human subject usingpatterns of null and non-null stimuli. Parts of the visual system for example,are presented with two simultaneous sequences of stimuli. Each sequence isvaried over time between a null stimulus and one or more less frequent non-null stimuli. The variation of each sequence is also controlled so thatneighbouring parts of the sensory system are less likely to receivesimultaneous non-null stimuli. The stimuli are therefore sparse both in timeand in some other aspect, typically a spatial dimension. One or more responsesof the subject are measured and weight functions are determined for assessmentof the sensory system.
