Objective: Prenatal exposure to inappropriate levels of glucocorticoids (GCs) and maternal stress are putative mechanisms for the fetal programming of later health outcomes. The current investigation examined the influence of prenatal maternal cortisol and maternal psychosocial stress on infant physiological and behavioral responses to stress.…

Collaboration is fundamental to our daily lives, yet little is known about how humans come to understand these activities. The present research was conducted to fill this void by using a novel visual habituation paradigm to investigate infants' understanding of the collaborative-goal structure of collaborative action. The findings of the three…

Although the psychophysics of infants' nonsymbolic number representations have been well studied, less is known about other characteristics of the approximate number system (ANS) in young children. Here three experiments explored the extent to which the ANS yields abstract representations by testing infants' ability to transfer approximate number…

One critical aspect of learning is the ability to apply learned knowledge to new situations. This ability to transfer is often limited, and its development is not well understood. The current research investigated the development of transfer between 8 and 16 months of age. In Experiment 1, 8- and 16-month-olds (who were established to have a…

Purpose: The present study examined the effects of age and hearing status of a child on maternal use of pitch change, preboundary vowel lengthening, and pause duration, all of which are prosodic cues correlated with clause boundaries in infant-directed speech. Method: Mothers' speech to infants with normal hearing (NH; n = 18), infants who are…

Both chimpanzees and human infants use the pointing gesture with human adults, but it is not clear if they are doing so for the same social motives. In two studies, we presented chimpanzees and human 25-month-olds with the opportunity to point for a hidden tool (in the presence of a non-functional distractor). In one condition it was clear that…

The purpose of the present study was to describe the rate of motor development in infants with Down syndrome in the age range of 3-12 months and identify the difficulties both in performance and acquiring motor skills in prone, supine, sitting and standing positions. Nineteen infants with Down syndrome and 25 healthy full term typical infants were…

The developing infant learns about the physical and the social world by engaging with objects and with people. In the study reported here, we investigated the relationship between infants' interactions with the physical and the social world. Three-month-old infants were trained for 2 weeks and experienced either actively manipulating objects…

Lexical stress is useful for a number of language learning tasks. In particular, it helps infants segment the speech stream and identify phonetic contrasts. Recent work has demonstrated that infants aged 1 ; 0 can learn two novel words differing only in their stress pattern. In the current study, we ask whether infants aged 1 ; 0 store stress…

Although there is much research on infants' ability to orient in space, little is known regarding the information they use to do so. This research uses a rotating room to evaluate the relative contribution of visual and vestibular information to location of a target following bodily rotation. Adults responded precisely on the basis of visual flow…

Pigeons responded in a perceptual categorization task with six different stimuli (shades of gray), three of which were to be classified as "light" or "dark", respectively. Reinforcement probability for correct responses was varied from 0.2 to 0.6 across blocks of sessions and was unequal for correct light and dark responses. Introduction of a new…

Perceptual narrowing--a phenomenon in which perception is broad from birth, but narrows as a function of experience--has previously been tested with primate faces. In the first 6 months of life, infants can discriminate among individual human and monkey faces. Though the ability to discriminate monkey faces is lost after about 9 months, infants…

Bhatt and Quinn (2011) review the substantial evidence that learning constrains perceptual organization in infants. With those findings as a foundation, they discuss five kinds of experiences that engender learning in infants and propose that attention and unitization mediate infant learning. Bhatt and Quinn's article is informative--the ideas…

How do infants use their knowledge of native language sound patterns when learning words? There is ample evidence of infants' precocious acquisition of native language sound structure during the first year of life, but much less evidence concerning how they apply this knowledge to the task of associating sounds with meanings in word learning. To…

Past research has shown that variation in the target objects depicting a given spatial relation disrupts the formation of a category representation for that relation. In the current research, we asked whether changing the orientation of the referent frame depicting the spatial relation would also disrupt the formation of a category representation…