Assessing the language of 2 year-olds: From theory to practice.

Early screening for language problems is a priority given the importance of language for success in school and interpersonal relationships. The paucity of reliable behavioral instruments for this age group prompted the development of a new touchscreen language screener for 2-year-olds that relies on language comprehension. Developmental literature guided selection of age-appropriate markers of language disorder risk that are culturally and dialectally neutral and could be reliably assessed. Items extend beyond products of linguistic knowledge (vocabulary and syntax) and tap the process by which children learn language, also known as fast mapping. After piloting an extensive set of items (139), two phases of testing with over 500 children aged 2; 0-2; 11 were conducted to choose the final 40-item set. Rasch analysis was used to select the best fitting and least redundant items. Norms were created based on 270 children. Sufficient test-retest reliability, Cronbach's alpha, and convergent validity with the MB-CDI and PPVT are reported. This quick behavioral measure of language capabilities could support research studies and facilitate the early detection of language problems.

Within and Across Language Predictors of Word Learning Processes in Dual Language Learners.

This study investigated the relation between Dual Language Learners' (N = 90) vocabulary and grammar comprehension and word learning processes in preschool (aged 3-through-5 years). Of interest was whether: (a) performance in Spanish correlated with performance in English within each domain; and (b) comprehension predicted novel word learning within and across languages. Dual-language experience was evaluated as a potential moderator. Hierarchical linear modeling revealed stronger predictive associations within each language than across languages. Across languages, results varied by experience and domain. Structural sensitivity theory suggests exposure to two languages heightens awareness of parameters along which languages vary and provides a framework for interpreting complex associations within and across languages. Knowledge from one language may influence learning in both.

Finding events in a continuous world: A developmental account.

Event segmentation is a fundamental process of human cognition that organizes the continuous flux of activity into discrete, hierarchical units. The mechanism of event segmentation in infants seems to parallel the mechanism studied in adults, which centers on action predictability. Statistical learning appears to bootstrap infants' event segmentation by generating action predictions without relying on prior knowledge. Infants' first-hand experiences with goal-directed actions further enhance their prediction of others' actions. Scaffolds for event segmentation are available in the input, with caregivers providing redundant cues to event boundaries through the use of motionese and acoustic packaging. Research points to the importance of developing event segmentation skills for development in other areas of cognition, including memory, social competence, and language, though more work is needed to capture the directionality of effects. Although event segmentation is a relatively new area of focus in cognition, this process illuminates how children make sense of an ever-changing world.

Keeping the end in mind: Preliminary brain and behavioral evidence for broad attention to endpoints in pre-linguistic infants.

Infants must learn to carve events at their joints to best understand who is doing what to whom or whether an object or agent has reached its intended goal. Recent behavioral research demonstrates that infants do not see the world as a movie devoid of meaning, but rather as a series of sub-events that include agents moving in different manners along paths from sources to goals. This research uses behavioral and electrophysiological methods to investigate infants' (10-14 months) attention to disruptions within relatively unfamiliar human action that does not rely on goal-objects to signal attainment (i.e., Olympic figure skating). Infants' visual (Study 1, N = 48) and neurophysiological (Study 2, N = 21) responses to pauses at starting points, endpoints, and within-action locations were recorded. Both measures revealed differential responses to pauses at endpoints relative to pauses elsewhere in the action (i.e., starting point; within-action). Eye-tracking data indicated that infants' visual attention was greater for events containing pauses at endpoints relative to events with pauses at starting points or within-actions. ERP activity reflecting perceptual processes in early-latency windows (<200 ms) and memory updating processes in long-latency windows (700-1000 ms) showed differential activation to disruptions at the end of a figure-skating action compared to other locations. Mid-latency windows (250-750 ms), in contrast, showed enhanced activation at frontal regions across conditions, suggesting electrophysiological resources may have been recruited to encode disruptions within unfamiliar dynamic human action. Combined, results hint at broad sensitivity to endpoints as a mechanism that supports infants' proclivity for carving continuous and complex event streams into meaningful units. Findings have potential implications for language development as these units are mapped onto budding linguistic representations. We discuss empirical and methodological contributions for action perception and address potential merits and pitfalls of applying behavioral techniques in conjunction with brain-based measures to study infant development.

A goal bias in action: The boundaries adults perceive in events align with sites of actor intent.

We live in a dynamic world comprised of continuous events. Remembering our past and predicting future events, however, requires that we segment these ongoing streams of information in a consistent manner. How is this segmentation achieved? This research examines whether the boundaries adults perceive in events, such as the Olympic figure skating routine used in these studies, align with the beginnings (sources) and endings (goals) of human goal-directed actions. Study 1 showed that a group of experts, given an explicit task with unlimited time to rewatch the event, identified the same subevents as one another, but with greater agreement as to the timing of goals than sources. In Study 2, experts, novices familiarized with the figure skating sequence, and unfamiliarized novices performed an online event segmentation task, marking boundaries as the video progressed in real time. The online boundaries of all groups corresponded with the sources and goals offered by Study 1's experts, with greater alignment of goals than sources. Additionally, expertise, but not mere perceptual familiarity, boosted the alignment of sources and goals. Finally, Study 3, which presented novices with the video played in reverse, indicated, unexpectedly, that even when spatiotemporal cues were disrupted, viewers' perceived event boundaries still aligned with their perception of the actors' intended sources and goals. This research extends the goal bias to event segmentation, and suggests that our spontaneous sensitivity toward goals may allow us to transform even relatively complex and unfamiliar event streams into structured and meaningful representations. (PsycINFO Database Record

Language Development in the First Year of Life: What Deaf Children Might Be Missing Before Cochlear Implantation.

OBJECTIVES: Language development is a multifaceted, dynamic process involving the discovery of complex patterns, and the refinement of native language competencies in the context of communicative interactions. This process is already advanced by the end of the first year of life for hearing children, but prelingually deaf children who initially lack a language model may miss critical experiences during this early window. The purpose of this review is twofold. First, we examine the published literature on language development during the first 12 months in typically developing children. Second, we use this literature to inform our understanding of the language outcomes of prelingually deaf children who receive cochlear implants (CIs), and therefore language input, either before or after the first year. CONCLUSIONS: During the first 12 months, typically developing infants exhibit advances in speech segmentation, word learning, syntax acquisition, and communication, both verbal and nonverbal. Infants and their caregivers coconstruct a communication foundation during this time, supporting continued language growth. The language outcomes of hearing children are robustly predicted by their experiences and acquired competencies during the first year; yet these predictive links are absent among prelingually deaf infants lacking a language model (i.e., those without exposure to sign). For deaf infants who receive a CI, implantation timing is crucial. Children receiving CIs before 12 months frequently catch up with their typically developing peers, whereas those receiving CIs later do not. Explanations for the language difficulties of late-implanted children are discussed.

Open-label, short-term, repetitive transcranial magnetic stimulation in patients with Alzheimer's disease with functional imaging correlates and literature review.

BACKGROUND: Accumulating evidence suggests repetitive transcranial magnetic stimulation (rTMS) may be beneficial in ameliorating cognitive deficits in Alzheimer's disease (AD). METHODS: AD patients received four high-frequency rTMS sessions over the bilateral dorsolateral prefrontal cortex (DLPFC) over two weeks. Structured cognitive assessments were administered at baseline, at 2 weeks after completion of rTMS, and at 4 weeks post treatment. At these same times, tolerant patients underwent functional magnetic resonance imaging (fMRI) while performing structured motor and cognitive tasks. We also reviewed literature regarding the effects of rTMS on cognitive function in AD. RESULTS: A total of 12 patients were enrolled, eight of whom tolerated the fMRI. Improvement was seen in Boston Diagnostic Aphasia Examination tests of verbal and non-verbal agility 4 weeks post-treatment. The fMRI analysis showed trends for increased activation during cognitive performance tasks immediately after and at 4 weeks post-treatment. Our literature review revealed several double-blind, sham-controlled studies, all showing sustained improvement in cognition of AD patients with rTMS. CONCLUSIONS: There was improvement in aspects of language after four rTMS treatments, sustained a month after treatment cessation. Our results are consistent with other studies and standardization of treatment protocols using functional imaging may be of benefit.