Previous research in adults has demonstrated the utility
of the visual evoked potential (VEP) to measure the integrity
of the chromatic and achromatic visual pathways. The VEP
has also been shown to be a valuable indicator of maturation
of these pathways in infants up to 1 year of age. The present
manuscript reports changes in the visual pathways from
2 years to adulthood as measured by the spatio-chromatic
VEP. The responses to achromatic reversal stimuli designed
to preferentially activate the low spatial-frequency achromatic
(luminance) pathways appear adult-like by 1 year of age.
The responses to low spatial-frequency isoluminant onset
stimuli designed to preferentially activate the chromatic
pathway do not appear as they do in the adult until after
12–13 years of age. The shapes of the chromatic VEP
waveforms shift from a positive–negative complex
to a negative–positive complex. These changes can
be modeled by a decrease in the latency of a large negative
component between the ages of 1 year and adulthood. The
results suggest that for low spatial-frequency stimuli,
there are long-term changes in the development of the chromatic
pathways that are not observed in the low spatial-frequency
achromatic pathways. The changes in the chromatic VEP waveforms
with age may be a physiological correlate of reported behavioral
changes.