Neural fine tuning during Vernier acuity training?

A superposition masking and summation to threshold paradigm was employed before and after unmasked Vernier acuity training to measure sensory changes of offset analysing mechanisms. Masking functions show a uniform downward translation after training and detection data reveal higher sensitivities to compound Gabor gratings in the post-test. These findings confirm the existence of learning related changes at early levels of information processing, but the results cannot be explained by neural fine tuning of offset analysing mechanisms. The data are consistent with the idea of task dependent broadening of orientation tuned mechanisms responsible for detecting small Vernier offsets.