Visual structure grips infants' attention. (Eye-Grabbing Insights).

Babies take their first major strides with their eyes, not their legs, as they rapidly distinguish among playpens, pacifiers, and a plethora of other objects. These feats of sight draw on infants' ability to keep track of pairs of shapes that regularly appear in the same spatial arrangement, according to a new study.

Sensitivity to such pairings in the visual world provides babies--by 9 months of age--with a foothold for learning to recognize all sorts of items, propose Jozsef Fiser and Richard N. Aslin of the University of Rochester (N.Y.) in an upcoming Proceedings of the National Academy of Sciences.

"Infants prefer to look at pairs of [shapes] that have frequently co-occurred in visual scenes and may use them to learn about more-complex visual features," the scientists note.

Fiser and Aslin studied 72 infants, all 9 months old. While sitting on a parent's lap, each child watched a set of randomly displayed scenes on a computer screen. Each scene contained three colored geometric shapes from a pool of 12 shapes. Eight shapes were grouped into four pairs that always appeared in the same arrangement, either one above the other or side-to-side. Each of the remaining four shapes was shown with a specific pairmate, but their relative locations varied from one scene to another.

The researchers presented the babies with an initial series of 16 scenes that was repeated until infant interest flagged. This usually took about seven repetitions. A new trial then presented a series of paired shapes, including the four pairs from the initial trials, shown on a plain background. Babies usually looked much longer at the pairings that had appeared in the scenes.

This result jibes with prior "looking-time" studies, which suggest that infants prefer to look at familiar material after they've tackled a complex task like viewing series of scenes. When faced with simpler tasks, babies look longer at novel stimuli.

In a second experiment, Fiser and Aslin varied the frequency with which specific pairs of shapes appeared in initial trials. In a subsequent trial, infants looked longer at the pairs that they had seen the greatest number of times.

"It's striking that 9-month-olds are exquisitely attuned to the spatial location of items and the frequency with which they occur together," comments psychologist Scott P. Johnson of Cornell University.

In the March Cognition, Johnson and his coworkers reported that infants as young as 2 months apparently recognize a simple and familiar sequence of six colored shapes shown to them earlier. In that experiment, the babies looked longer at novel sequences of shapes than at familiar sequences.

The precise ways in which such visual recognition by infants fosters their learning of different objects in the environment remain unclear.