The equality of quantity.

Do disparate dimensions of magnitude share an underlying mental representation? Two recent papers offer suggestive evidence that participants' discrimination thresholds are identical across domains. Brannon, Lutz and Cordes showed that six-month-old infants' area discriminations match their number discriminations. VanMarle and Wynn demonstrated the same pattern for six-month-olds' discrimination of temporal duration. These parallels across infants' responses to number, area and time raise questions about the fundamental nature of quantity processing.