Table 2.

Neurobehavioral development assessed in differentially-reared rhesus macaques at different developmental ages

	Mother-reared (n=15)
	PND 7	PND 14	PND 21	PND 30
Activity cluster	0.9±0.1	1.2±0.1	1.5±0.02	1.5±0.03
Predominant state	0.5±0.1	0.8±0.2	1.0±0.1	1.5±0.1 ‡
	Peer-reared (n=12)
	PND 7	PND 14	PND 21	PND 30
Activity cluster	1.0±0.1	1.4±0.1	1.3±0.1	1.2±0.1 *
Predominant state	0.1±0.1	0.1±0.1	0.1±0.1	0.2±0.1

Peer-rearing affected neurological development of infants, differences becoming evident on PND 30. PR subjects did not display agitated behavior in response to the examination (scored as “Predominant state”) as MR infants did (‡ = age by rearing condition interaction; p = 0.0001). In addition, lower scores of “Activity” characterized PR infants (* p < 0.05). Abbreviations as in Figure 1 and 2