Retinal and cortical pattern responses: a comparison of infants and adults.

Retinal and cortical responses to pattern reversal stimulation were recorded simultaneously in three human infants of average age 3.5 months and two adults of average age 28.5 years. The relative power of retinal signals as a function of spatial frequency for both adults and infants was very similar and extrapolated to a threshold of about 30 c/deg [6/6 (20/20)] as did the relative power of the adult cortical signal. The infant cortical signal was relatively more attenuated at higher spatial frequencies and extrapolated to a threshold of 8.5 c/deg [6/22.2 (20/74)]. A greater relative maturity of retinal as compared with cortical neural function in 3.5-month-olds is inferred.