Research

Abstract

The HEALthy Brain and Child Development (HBCD) study, a multi-site prospective longitudinal cohort study, will examine human brain, cognitive, behavioral, social, and emotional development beginning prenatally and planned through early childhood. The study plans enrolling over 7000 families across 27 sites. This manuscript presents the measures from the Neurocognition and Language Workgroup. Constructs were selected for their importance in normative development, evidence for altered trajectories associated with environmental influences, and predictive validity for child outcomes. Evaluation of measures considered psychometric properties, brevity, and developmental and cultural appropriateness. Both performance measures and caregiver report were used wherever possible. A balance of norm-referenced global measures of development (e.g., Bayley Scales of Infant Development-4) and more specific laboratory measures (e.g., deferred imitation) are included in the HBCD study battery. Domains of assessment include sensory processing, visual-spatial reasoning, expressive and receptive language, executive function, memory, numeracy, adaptive behavior, and neuromotor. Strategies for staff training and quality control procedures, as well as anticipated measures to be added as the cohort ages, are reviewed. The HBCD study presents a unique opportunity to examine early brain and neurodevelopment in young children through a lens that accounts for prenatal exposures, health and socio-economic disparities.

This review seeks to describe the complexities of binaural fusion, highlight measurement challenges, provide guidelines for rigorous perceptual measurements, and provide a working definition that encompasses this information. First, it is argued that binaural fusion may be multidimensional and might occur in one domain but not others, such as fusion in the spatial but not the spectral domain or vice versa. Second, binaural fusion may occur on a continuous scale rather than on a binary one. Third, binaural fusion responses are highly idiosyncratic, which could be a result of methodology, such as the specific experimental instructions, suggesting a need to explicitly report the instructions given. Fourth, it is possible that direct (“Did you hear one sound or two?”) and indirect (“Where did the sound come from?” or “What was the pitch of the sound?”) measurements of fusion will produce different results. In conclusion, explicit consideration of these attributes and reporting of methodology are needed for rigorous interpretation and comparison across studies and listener populations.

Our purpose is to highlight the contributions of TalkBank initiatives to improved understanding of clinical impairments in adult and child speakers and examine remaining challenges and proposed solutions.We review the origins and development of TalkBank initiatives that have targeted a wide array of typical and atypical child and adult populations. In particular, we discuss how such sets of data have given rise to evaluation and validation of traditional measures used to appraise spoken language performance. The durable contributions of AphasiaBank and CHILDES archives are already evident in a body of published research that has re-evaluated, refined and reconceptualized how we evaluate and set therapeutic goals for speakers with expressive speech and language impairments. More recent archival initiatives, such as PhonBank and FluencyBank, are also making impacts. Beyond improvements in basic and applied science in communication development and disorders, archival data are also being used to test and improve accessibility for communicatively impaired speakers. TalkBank has transformed how research in communication disorders is conducted. It no longer relies on small, unshared research ventures that enable limited clinical impact or follow-up research inquiries. Rather, it has enabled large-scale, more generalizable research more likely to spur further research and enable more rapid translation to clinical practice.

Cochlear implants (CIs) provide precise temporal information that listeners use to understand speech. Other acoustic cues are not conveyed as precisely, making unambiguous temporal speech cues vital to a listener's ability to understand speech. Several speech sounds are differentiated by small differences in the timing of acoustic features. Previous studies have shown differences in the perception of these differences, depending on whether the speech sound was heard in a single word or embedded in a sentence. This study expands on previous research by exploring forward masking as a possible contributor to the mechanisms driving the effects observed when temporal cues were embedded in sentences. Listeners using CIs performed a phoneme categorization task on words from four continua that each varied mainly on a single temporal dimension. The differentiating phonemes were located at the beginning of the word in two continua and at the end of the word in two others. Silent intervals of 0, 25, 50, 75, and 100 ms between the preceding sentence and the target words were tested. Results showed an increasing effect on performance as the inter-stimulus interval duration decreased for the two word-initial phonemic contrasts, lending support to forward masking as an influence on speech understanding.

Language acquisition research has a long tradition of including individuals with disabilities as research subjects. Numerous early works had the goal of using what was “missing” in their development to inform theories of how the system “ought” to function. More recent decades have seen a shift toward understanding individuals with disabilities as their own functional systems that are worth describing and also toward ensuring that this research benefits individuals from these communities. This shift has, to some extent, created a disconnect between work on “typical” development and on clinical populations, which have largely progressed independently of each other. The former is concentrated more in departments of Linguistics and (Cognitive) Psychology, while the latter is concentrated more in departments of Communication Sciences and Disorders (and its other associated names). Their shared past and overlapping constructs are masked by differences in goals—to understand basic acquisition processes vs. to support functional communication in those who may not fit within normative societal standards.

Many children speak language varieties (dialects), such as African American English (AAE) that differ from the language variety typically used in academic settings and in literacy instruction (Mainstream American English, MAE). There has been considerable work suggesting a negative correlation between use of a non-mainstream dialect and lower literacy scores, suggesting that early instruction on dialect differences might be helpful for non-mainstream dialect speakers. We tested this for a population of AAE-speaking children in kindergarten and first grade. Schools were randomly assigned to teach a curriculum that explicitly compares MAE and AAE or to a business-as-usual control. While students in both the intervention and control conditions showed increased usage of MAE and greater decoding skills over time, there was no condition effect for decoding skills and minimal evidence of a condition effect for recognition of different dialects. We discuss potential limitations of the curriculum and other considerations for supporting AAE-speaking children as they start school.