Infants' pointing is associated with concurrent and later language development. The communicative intention behind the point -- i.e., imperative versus declarative -- can affect both the nature and strength of these associations, and is therefore a critical factor to consider. Parents' pointing is associated with both infant pointing and infant…

Typically developing (TD) children refer to objects uniquely in gesture (e.g., point at a cat) before they produce verbal labels for these objects ("cat"). The onset of such gestures predicts the onset of similar spoken words, showing a strong positive relation between early gestures and early words. We asked whether gesture plays the…

Differences in vocabulary that children bring with them to school can be traced back to the gestures they produced at the age of 1;2, which, in turn, can be traced back to the gestures their parents produced at the same age (Rowe & Goldin-Meadow, 2009a). We ask here whether child gesture can be experimentally increased and, if so, whether the…

Language acquisition is a process embedded in social routines. Despite considerable attention in research to its social nature, little is known about developmental differences in the relative priority of certain social cues over others during early word learning. Employing an eye-tracking paradigm, we presented 14-month-old infants, 24-month-old…

U-shaped developmental functions, and their N-shaped cousins, have intrigued developmental psychologists for decades because they provide a compelling demonstration that development does not always entail a monotonic increase across age in a single underlying ability. Instead, the causes of development are much more complex. Indeed,…

When a behavior disappears and then resurfaces, developmental psychologists typically look more closely at the behavior to figure out what is different before and after--that is, they increase the grain with an eye toward discovering how the system that generates that behavior has changed. But what ought to count as a U-shaped phenomenon? How…

The development of the "inversion" effect in face processing was examined in infants 3 to 6 months of age by testing their integration of the internal and external features of upright and inverted faces using a variation of the "switch" visual habituation paradigm. When combined with previous findings showing that 7-month-olds use integrative…

The aim of this article is to introduce readers to an alternative way of applying U-shaped functions to understand development, especially cognitive development. In classical developmental applications, age is the abscissa; that is, in the fundamental equation B = f(A), some behavioral variable (B) plots as a U-shaped or inverted U-shaped function…

The articles in this collection consider one very interesting puzzle of development: U-shaped developmental functions. At some point during development, an organism might exhibit what seems like a regression from its expected developmental trajectory and, according to continuity models of development, this is aberrant. In this special issue,…

Interest in U-shaped development has itself undergone a U-shaped progression. Twenty-five years ago, interest in U-shaped development was high. This interest was evident at a 1978 conference in Tel Aviv on "U-shaped Behavioral Growth" that resulted in the publication of a book of the same title 4 years later (Strauss, 1982). The breadth…

It has been 20 years since Bever's (1982) and Strauss and Stavy's (1982) books on U-shaped functions in human development were published. The three target articles in this issue describe several old and new U-shaped functions and new theoretical explanations for their existence. In this article, the authors will comment on two aspects of U-shaped…