Comparison of ganglion cell signals and psychophysical localization of moving targets can help define central motion mechanisms.

Vernier acuity thresholds can be related to visibility of targets. This is considered in relation to retinal signals. Spatial precision of macaque ganglion cell responses to moving targets was assessed by neurometric analysis and compared with psychophysical performance. Under some conditions the amplitude of ganglion cell signals per se may relate target visibility to spatial precision of psychophysical performance. Other conditions are more complex; we suggest central mechanisms may adapt their properties, eg their dimensions, depending on the stochastic properties of ganglion cell signals. Thus, the relation of Vernier acuity to the visibility of targets is a rule of thumb which has a complex relation to physiological substrates.