Infants' early motor actions help organize social interactions, forming the context of caregiver speech. We investigated changes across the first year in social contingencies between infant gaze and object exploration, and mothers' speech. We recorded mother-infant object play at 4, 6, and 9 months, identifying infants' and mothers' gaze and hand actions, and mothers' object naming and general utterances. Mothers named objects more when infants vocalized, looked at objects or the mother's face, or handled multiple objects. As infants aged, their increasing object exploration created opportunities for caregiver contingencies and changed how gaze and hands accompany object naming over time.

Infants' early motor actions help organize social interactions, forming the context of caregiver speech. We investigated changes across the first year in social contingencies between infant gaze and object exploration, and mothers' speech. We recorded mother-infant object play at 4, 6, and 9 months, identifying infants' and mothers' gaze and hand actions, and mothers' object naming and general utterances. Mothers named objects more when infants vocalized, looked at objects or the mother's face, or handled multiple objects. As infants aged, their increasing object exploration created opportunities for caregiver contingencies and changed how gaze and hands accompany object naming over time.

BackgroundThe Molecular Interaction Map (MIM) notation offers a standard set of symbols and rules on their usage for the depiction of cellular signaling network diagrams. Such diagrams are essential for disseminating biological information in a concise manner. A lack of software tools for the notation restricts wider usage of the notation. Development of software is facilitated by a more detailed specification regarding software requirements than has previously existed for the MIM notation.ResultsA formal implementation of the MIM notation was developed based on a core set of previously defined glyphs. This implementation provides a detailed specification of the properties of the elements of the MIM notation. Building upon this specification, a machine-readable format is provided as a standardized mechanism for the storage and exchange of MIM diagrams. This new format is accompanied by a Java-based application programming interface to help software developers to integrate MIM support into software projects. A validation mechanism is also provided to determine whether MIM datasets are in accordance with syntax rules provided by the new specification.ConclusionsThe work presented here provides key foundational components to promote software development for the MIM notation. These components will speed up the development of interoperable tools supporting the MIM notation and will aid in the translation of data stored in MIM diagrams to other standardized formats. Several projects utilizing this implementation of the notation are outlined herein. The MIM specification is available as an additional file to this publication. Source code, libraries, documentation, and examples are available at http://discover.nci.nih.gov/mim.

Infant language learning depends on the distribution of co‐occurrences within language–between words and other words–and between language content and events in the world. Yet infant‐directed speech is not limited to words that refer to perceivable objects and actions. Rather, caregivers’ utterances contain a range of syntactic forms and expressions with diverse attentional, regulatory, social, and referential functions. We conducted a distributional analysis of linguistic content types at the utterance level, and demonstrated that a wide range of content types in maternal speech can be distinguished by their distribution in sequences of utterances and by their patterns of co‐occurrence with infants’ actions. We observed free‐play sessions of 38 12‐month‐old infants and their mothers, annotated maternal utterances for 10 content types, and coded infants’ gaze target and object handling. Results show that all content types tended to repeat in consecutive utterances, whereas preferred transitions between different content types reflected sequences from attention‐capturing to directing and then descriptive utterances. Specific content types were associated with infants’ engagement with objects (declaratives, descriptions, object names), with disengagement from objects (talk about attention, infant's name), and with infants’ gaze at the mother (affirmations). We discuss how structured discourse might facilitate language acquisition by making speech input more predictable and/or by providing clues about high‐level form‐function mappings.