Table 2.

Studies of visual acuity development using VEP.

First Author	Year	Subjects’ Age Range	Results
Sokol [100]	1978	Infants: 2–6 months Adults	VEP acuity improved from 20/150 at 2 months to 20/20 by 6 months.
Norcia [13]	1985	Infants: 17–25 weeks	Temporal frequency of 6 or 10 Hz did not affect estimation of sVEP acuity. Sweep technique was also a robust method for measuring visual acuity.
Norcia [14]	1985	Infants: 1–53 weeks Adults	VEP acuity increased from 4.5 cpd in the first month to about 20 cpd at 8–13 months. By 8 months, VEP acuity reached adult level.
Sokol [73]	1988	Infants: 2–10 months Adults	Grating acuity was temporally tuned at 7.5 or 14 rps for infants at 3 months and older. Difference between VEP and PL acuity decreased from 2.0 octaves at 2 months to 0.5 octaves at 12 months.
Hamer [124]	1989	Infants: 2–52 weeks	Monocular and binocular acuity growth functions were nearly identical; monocular and binocular VEP acuity increased from 6 cpd at 2–10 weeks to 14 cpd by 20–30 weeks.
Norcia [65]	1990	Infants: 2–40 weeks Adults	SVEP estimated grating acuity showed gradual increase with age, ranging from 2.5–9 cpd in the first 2 months to about 10–20 cpd after 30 weeks.
Sokol [74]	1992	Infants: 2–13 months Children: 1–5 years Adults: 22–48 years	VEP and PL acuity developed at different rates, reaching a nearly equivalent level by 12 months. PL acuity in infants older than 2 years was found to be not temporally tuned.
Allen [19]	1992	Infants: 15–20 weeks Adults	FPL acuity improved slightly more with luminance than did VEP acuity. Acuity levels of VEP and FPL were comparable, with VEP slightly higher.
Riddell [121]	1997	Pre-term infants: 2–8 months Full-term infants: 3 weeks to 1 year	VEP acuity was generally higher than TAC acuity, but the rate of development was higher for TAC than VEP. TAC acuity reached VEP acuity at about 14 months. There was no difference between pre-term and full-term infants in VEP and TAC acuity.
Skoczenski [66]	1999	Infants: 8–80 weeks Adults	VEP Vernier and grating acuity developed at different rates, the former approaching adult levels earlier than the latter. Vernier acuity increased by a factor of 4.5 between 10 and 100 weeks; grating acuity improved by a factor of 2.3.
Prager [93]	1999	Infants: 4–8 months	Correlations among transient VEP, sVEP, and TAC acuity were poor, but expected changes in visual maturation from 4 to 8 months were detected with all methods. SVEP acuity increased from 9.61 cpd at 4 months to 10.39 cpd at 8 months.
Suttle [91]	2000	Infants: 6–17 weeks	Most infants did not exhibit clear VEP to whole-field flicker alone. Estimated VEP acuity was generally not confounded by front-end nonlinear distortion products.
Maria [101]	2001	Infants: 15.2–17.7 weeks	Perinatal characteristics including birth weight, gender, and number of smokers in the household needed to be considered for VEP acuity.
Lauritzen [81]	2004	Infants: 6–40 weeks	Mean rather than maximum threshold best estimated visual acuity. VEP method was well suited to describe visual development in infants, which increased by 0.64 octaves per doubling in age for acuity.
Salomão [99]	2008	Infants/children: 1–36 months	Age norms for grating acuity were determined using sweep VEP technique. Sweep VEP grating acuity ranged from 0.80 logMAR in the first month to 0.06 logMAR at 36 months.
Lenassi [35]	2008	Infants/children: 1.5 months to 7.5 years	VEP latency was strongly associated with visual acuity, recommending VEP latency as a reliable parameter for evaluating the integrity of the afferent visual pathway.
Almoqbel [109]	2017	Children: 6–7, 8–9, 10–12 years Adults	Results of various procedures (sweep VEP, psychophysical logMAR letter, and grating visual acuity) were in agreement. There were age-related changes in the visual acuity threshold after 6 years of age and visual acuity did not become adult-like until 8 to 9 years at the earliest.