Current Projects

 

Our research is interdisciplinary and is conducted across multiple sites. Undergraduate RAs interested in working on studies at the UConn lab have opportunities to contribute to any project labeled as “currently researching at UConn.” Prospective graduate students or other collaborators can contribute to any project, whether it is currently at UConn or not.


Dyslexia — currently researching at UConn

From the beginning, the goal of understanding the neural basis of reading skill variability and clinical reading disability (or Dyslexia) has been central to our work.   Findings from our lab and others have shown that the core deficit in developmental dyslexia (or reading disability (RD)) lies within the language system, most prominently at the level of phonological processing and analysis. Moreover, a significant body of neuroimaging research has now established a common neurobiological characteristic of RD as a disruption across a number of critical left-hemisphere (LH) reading-related sites. This disruption typically manifests as an under activation relative to non-impaired (NI) individuals and is primarily observed in both LH temporoparietal and LH occipitotemporal (OT) regions. Moreover, this relative under activation is particularly pronounced during tasks that require printed word processing or make explicit demands on phonological processing or analysis, e.g., a rhyme task (e.g., Landi et al 2010; Pugh et al 2013). In more recent years we have been: a) Taking a closer look at the role of subcortical structures  — and in particular have found that (using fMRI & sMRI) the thalamus and putamen contribute to reading ability, and must be considered as part of the reading circuit (Preston et al. 2010; Preston et al. 2013; Pugh et al. 2013) b) Identifying genes associated with RD, specifically we identified the COMT Val/ Met polymorphism to be one potential common mutation associated with RD (Landi et al. 2013), and have further explored why rare “candidate genes” may fail to represent the full heritability of RD identified by twin studies (Skiba, Landi, Wagner & Grigorenko, 2010) and C) Exploring the and neurochemical expression as it relates to reading ability/disability (Pugh et al. 2014) – initial findings reveal that choline and glutamate are negatively correlated with reading ability; This  data provides new information on potential neurobiologic pathways (e.g., hyperexcitability and abnormal white matter organization) in atypical development, and points to new directions for research on gene-brain-behavior pathways in reading disability. (Pugh et al. 2014).

Team: Nicole Landi, Ken Pugh, W.E. Mencl, Stephen Frost, Jonathan Preston, Elena Grigorenko, Robert Fulbright, Fumiko Hoeft, Kaja Jasinska, Mark Seidenberg, Leslie Jacobsen, Stephanie Del Tufo, Sergey Kornilov, Kayleigh Ryherd, Meaghan Perdue

Funding: R03 HD053409 (N. Landi, PI) Neurocognitive development in RD children with/without general cognitive deficits. P01 HD 01994 Project 3 (K. Pugh, PI), Program Project PI: Carol Fowler; R01 HD 48830. (K. Pugh, PI) Neurobiological Foundations of Reading (Dis)ability; RO1 40411 (K. Pugh PI). Cognitive and Neurobiological Mechanisms of Reading and Reading Disability

* see publications for PDF copies of  all works cited


Comprehension Impairment — currently researching at UConn

Like RD, one goal of the lab from the earliest years has been to better understand specific comprehension impairment; on some estimates, 10% of children adolescents and young adults have this specific problem. Individuals with specific deficits in comprehension (and strengths in single word reading and phonological awareness) have been reported to have reduced semantic priming, trouble generating text-appropriate inferences, monitoring their comprehension progress using relevant semantic information processing syntactically complex sentences and holding information online in working memory all despite seemingly normal decoding ability. Our earliest work with this group of individuals provided the first neurobiological evidence for semantic processing deficits (using ERP) in this population (Landi & Perfetti, 2007). From there we went on to show that individuals with specific comprehension impairments are as common as individuals with Dyslexia (in a population study, Landi, 2010), and that comprehension and sub serving skills such as vocabulary were orthogonal to word reading and phonological awareness (Landi, 2010). Currently, through a recently funded NIH grant, we are exploring a large population of poor comprehenders across a variety of tasks aimed at dissociating the contributions of domain general function to CI (e.g., working memory, executive dysfunction) and linguistic contributions (semantic processing, syntactic processing, prosodic processing) – this work, like our other projects employs multiple methodologies including ERP, fMRI, DTI and genetic analyses).

Team: Nicole Landi, Julie Van Dyke, Whit Tabor, Mark Seidenberg, Jim Magnuson, Clint Johns, Mara Breen, Jelena Krivokapic, Chuck Clifton, Gina Kuperberg, Nina Gumkowski, Emily Baron, Eva Montas, Kayleigh Ryherd

Funding: P01 HD001994-46, Project 4: Examinations of skilled and impaired spoken and written comprehension (Landi, PI), Program Project PI: Jay Rueckl.

* see publications for PDF copies of  all works cited


SLI — currently researching at UConn

Our work on Developmental Language Disorders (DLD; the most frequently term used to refer to this condition is Specific Language Impairment or SLI), focuses on a rural northern Russian geographically isolated population (the AZ population). Dr. Elena L. Grigorenko, a close collaborator started the epidemiological study of DLD in the AZ population in 2003. A more focal subset of our lab became strongly involved in 2008, when we, collaboratively, brought a portable EEG/ERP system to the region collect EEGs associated with multiple levels of language and language-related processing – this would add a neural component to this large-scale epidemiological study of genetic bases of DLD. The main aims of the joint Yale-UConn-Haskins ERP study are to: 1) evaluate a wide range of neurophysiological endophenotypes of DLD in children that come from an isolated Russian-speaking population in Russia’s rural North, and 2) to potentially link these endophenotypes to genetic variants discovered through the genome-wide association study (GWAS) that is the major component of the project overall. The EEG/ERP component of the AZ project is unique with respect to its breadth (i.e., we are examining neural indices of attentional and pre-attentive auditory processing, lexical-semantic processing, syntactic processing, and the functioning of attentional networks in the same sample of children) and the sample characteristics (i.e., the participants come from a population that is geographically isolated, environmentally homogenous and displays a significantly elevated prevalence of DLD, presumably of genetic etiology). Our first report which outlines tonal P3 and speech associated MMN responses in affected (DLD) and their typically developing (TD) peers is currently under review (Kornilov et al. under review); the second manuscript describing the specifics of lexical-semantic processing deficits in DLD is currently in preparation.

Team: Nicole Landi, Elena L. Grigorenko, Jim Magnuson, Sergey A. Kornilov, Natalia Rakhlin, Meaghan Perdue

Funding: R01 DC007665 (E. Grigorenko, PI), NSF CAREER 0748684 (J. Magnuson, PI), NSF IGERT 114399 (J. Magnuson, PI), PO1 HD1994 (J. Rueckl, PI).

* see publications for PDF copies of  all works cited

 

Autism Spectrum Disorders — currently researching at UConn

Our work on school aged Children with ASD, initially led by collaborator Julia Irwin, uses electroencephalography (EEG) and event related potentials (ERP) paired with eye-tracking technology to examine perception and imitation of speaking faces in children with autism spectrum disorders (ASD).  The goal of this project is to provide a more sophisticated understanding of the factors that underlie perception and imitation of audiovisual speech in children with ASD.  In addition to children with ASD, we are also examining two control groups one with disorders of spoken language (DSL) that have similar language and cognitive profiles to children with ASD, but no social impairments, as well as typically developing (TD) chronologically age matched children. The aims of this project are to 1) identify a neurobiological signature of auditory and audiovisual (AV) speech perception, 2) to examine patterns of EEG connectivity during AV speech perception tasks and 3) to assess potential underlying group differences during perception and imitation of visually presented spoken language.

Team: Nicole Landi, Julia Irwin, Jonathan Preston, Larry Brancazio, Kimberly Cuevas, Nina Gumkowski, Jackie Turcios, Kayleigh Ryherd

Funding: R21 DC011342 (J. Irwin PI) Neurobiological signatures of audiovisual speech perception in children in ASD

* see publications for PDF copies of  all works cited

 

Childhood Apraxia of Speech — not currently researching at UConn

Childhood apraxia of speech (CAS) is a subtype of speech sound disorder that impacts speech intelligibility through impaired precision and consistency of speech sounds. CAS is a motor speech disorder characterized by disrupted transitions between sounds and impairments in prosodic elements of speech such as lexical stress. One manifestation of CAS is significant breakdown in the precision of speech as words become increasingly complex.  Although CAS is believed to have a neurobiological basis that results in an impaired ability to plan and/or program the movements for speech (ASHA, 2007), there is currently little understanding of the neurobiological foundation of the deficits in producing complex word forms and planning and programming movements. CAS is often identified in early childhood but symptoms can remain well into school age or even adulthood, and there may be lasting impacts on social, academic, and communicative success. Much behavioral research has been conducted on CAS, but few studies have addressed neurobiological foundations of the disorder. Our work in with this population was started by collaborator Jon Preston, and the lab became strongly involved when co investigators Preston and Landi were awarded a CASANA grant that a) aims to characterize the neurobiological basis (using ERP) of motor planning and production in children with Apraxia of speech (Preston et al. under review) and b) to explore the use of ultrasound feedback therapy to treat children with Apraxia of speech who have been resistant to treatment as usual (Preston, Brick and Landi 2013).

Team: Nicole Landi, Jon Preston, Jessica Whittle, Erik Landry, Nicole Brick

Funding: Childhood Apraxia of Speech Association of north America (CASANA) Treatment Award: Biofeedback training for children with persisting CAS:  Articulatory and neural changes (J. Preston and N. Landi Co- Investigators)

* see publications for PDF copies of  all works cited

 

In-utero Exposure to Cocaine and Other Substances — not currently researching at UConn

Prenatal cocaine exposure (PCE) can have significant effects on neural development and cognition, with language skills routinely affected. Better understanding this relationship is critical as childhood language skill has been directly linked to later academic and social success as well as to decreased incidence of criminal behavior (Mages & Alexander, 2008). Extant findings have revealed multiple deficits/delays in language function associated with PCE including: 1) delayed age of acquisition, 2) poorer receptive language, 3) poorer expressive language, and 4) abnormal physiological response to speech. The specific pattern of findings observed indicate language processing deficits ranging from low-level perceptual impairments (e.g., speech processing) to more metacognitive deficits (e.g., syntax, comprehension). However, whether these deficits stem from the same or different underlying neurobiological anomalies is not known.  Our work is using EEG, ERP and genetic data  (along with careful behavioral phenotyping) to further explore the extent of the language deficits in adolescents who have been followed prospectively since birth – thus we examine auditory and linguistic processing in these children from low level tone and speech processing to high level comprehension impairment). Critically we are also examining whether common mutations on dopamine regulating genes mediate these outcomes. See Landi et al. 2011 for an initial report from this funded NIH project.

Team: Nicole Landi, Linda C. Mayes, Michael Crowley, Jia Wu, Jasmine Coleman, Dianna Gal

Funding: R21 DA030665 (N. Landi, PI) Neurobiology of language function in adolescents exposed to cocaine in utero.

* see publications for PDF copies of  all works cited

 

Late Talkers — not currently researching at UConn

The identification of neurocognitive precursors of learning disabilities (LD) is of great theoretical and educational significance. Building upon existing initiatives at both Haskins Laboratories and the Yale Child Study Center, the overarching goal of this project is to examine development in complex (and often understudied) populations of children at heightened risk for disorders of language and reading as well as non-language domain specific skills such as math.  The project is grounded by recent findings from our group and others that indicates that elevated rates of deficits in language, reading and mathematical proficiency in school-aged children are traceable to one of the earliest risk markers – “late talking”. Early diagnosis and intervention play a critical role in advancing language development for toddlers with language delay. However, late talking toddlers are a perplexing population for clinicians due to the vast variability in language performance within the group. Many children identified late talkers or having specific language impairment (SLI) within the early pre-school years continue to have persistent language deficits, whereas others will not. Difficulties in early diagnosis are problematic in the face of consistent evidence that early and intensive language intervention provides the best means for improvement of skills. By determining which toddlers are most at risk for future language problems early on, it is possible to capitalize on childhood neuroplasticity and cultivate meaningful language gains. A contributing factor to difficulties in early differential diagnosis for late talkers is poor diagnostic accuracy of many of the commonly used assessment measures.  Assessment practices for toddlers utilize standardized testing as a means to capture language performance.  However, standardized assessments for very young children are not without limitations.  First, there are few standardized language assessments normed for children as young as 18-36 that have good sensitivity and specificity.  Second, standardized assessments used for the toddler population are lacking in their ability to accurately determine the nature and severity of impairment as well as demonstrate adequate predictive validity which provides information on how well the child will perform in the future learning deficits. Our project seeks to identify early biomarkers that can be assessed in children before they are talking. We use both EEG/ERP and Near Infrared Spectroscopy (NIRS) to examine multiple aspects of auditory linguistic processing (along with known standardized assessments, and behavioral experimental measures designed to better capture linguistic knowledge).

Team: Nicole Landi, Jonathan Preston, Julia Irwin, Heather Bortfeld, Ken Pugh, Vanessa Harwood, Bernard Grela

Funding: Private donation.

* see publications for PDF copies of  all works cited

 

Craniosynostosis/Plagiocephaly — not currently researching at UConn

Two projects, in which our lab collaborates, are looking at neurodevelopmental outcomes of deformational plagiocepaly in infancy and the other exploring these outcomes in infants with single suture Craniosynostosis – these projects are led by Drs. John Persing, MD and Peter Hashim, MD, at Yale Medical School.

Deformational plagiocephaly is a common head shape disorder that is characterized by unilateral occipital flattening and asymmetric frontal bossing. The condition, also known as positional plagiocephaly, plagiocephaly without synostosis, or flat head syndrome, develops due to mechanical forces acting on the skull in utero or early in life. Multiple-gestation pregnancies, prematurity, and forceps-assisted delivery have been identified as risk factors. Skull deformity secondary to uterine constraint may improve within the first few weeks of life, whereas flattening from supine post-natal positioning (with or without associated torticollis) tends to progressively worsen if no alterations in sleeping habits or corrective therapy are implemented. characteristic cranial asymmetry of deformational plagiocephaly remains an important consideration for craniofacial specialists, as similar head shapes result from unicoronal craniosynostosis (anterior plagiocephaly) and lambdoid craniosynostosis (posterior plagiocephaly). At present, the developmental implications of deformational plagiocephaly are poorly understood. Miller and colleagues reported that children with persistent plagiocephaly utilize more school-associated special help programs relative to their healthy siblings. Standardized developmental assessment with the Bayley Scales of Infant Development (BSID) has shown that patients with deformational plagiocephaly obtain below average scores on the test’s cognitive and motor indices.

Single-suture craniosynostosis (SSC) is  a condition in which one of the fibrous sutures in an infant skull fuses prematurely, and thus changes the growth pattern of the skull. The impact of on intellectual development remains an important concern for craniofacial specialists, pediatricians, and parents. As the methods of neurologic testing have advanced, associations between cranial deformity and cognitive outcomes have gradually evolved. Originally considered a solely cosmetic condition, SSC is now linked to a number of developmental difficulties. In particular, studies using long-term neuropsychological testing have demonstrated that individuals previously treated for SSC exhibit normal intelligence but face a heightened risk for learning impairments. Greater understanding of infant brain abnormalities in SSC is needed, as the early detection of neural dysfunction may help to clarify the etiology of long-term delays, and in turn, guide surgical management.

In both groups of infants we are collecting EEG and ERP data to auditory information, in addition to behavioral measures of cognitive development as we follow them prospectively. See Hashim et al. (in press)

Team: Nicole Landi, John Persing, Peter Hashim, Jamie McPartland, Linda Mayes, Robert Travesio,

* see publications for PDF copies of  all works cited