Early operant learning is unaffected by socio-economic status and other demographic factors: a meta-analysis.

The relation between SES (socioeconomic status) and academic achievement in school-aged children is well established; children from low SES families have more difficulty in school. However, few studies have been able to establish a link between SES and learning in infancy, and thus the developmental onset of SES effects remains unknown. The limited studies that have been conducted to explore the link between SES and learning in infancy have generated mixed results; some demonstrate a link between SES and learning in infants as young as 6-9 months (Smith, Fagan, & Ulvund, 2002) while others do not. Further, studies examining the genetic as well as environmental contributors to learning in infancy and early childhood suggest that the effect of SES is likely cumulative and that as children develop, the effect of a low SES environment will become more pronounced (Tucker-Drob, Rhemtulla, Harden, Turkheimer, & Fask, 2011). Using aggregated data from 790 infants collected across 18 studies, we examined the contribution of SES and other demographic factors to learning of an operant kicking task in 2-4-month-old infants in a meta-analysis. Results indicated that, at least with respect to operant conditioning, an infant is an infant; that is SES did not affect learning rate or ability to learn in infants under 4-months of age. SES effects may therefore be better characterized as cumulative, with tangible effects emerging sometime later in life.