Other evidence, however, including neuroimaging and physiology converges on V4 as necessary to color perception. A recent meta-analysis has also shown a specific lesion common to achromats corresponding to V4. From another direction altogether it has been found that when synaesthetes experience color by a non-visual stimulus, V4 is active.
Research from various fields, including neuroimaging and physiology, points to V4 as crucial for color perception. A recent study also identified a specific lesion in achromats corresponding to V4. Interestingly, synaesthetes who experience colors through non-visual stimuli show activation of V4.