Bio

Bio


Dr. Katherine Travis is an Assistant Professor in the Division of Developmental-Behavioral Pediatrics at Stanford University. Dr. Travis obtained her Ph.D. in Neuroscience from the University of California San Diego. Dr. Travis came to Stanford as a postdoctoral fellow to obtain training in clinical neuroscience and translational approaches to intervention. As part of her training, she was awarded a K99/R00 Pathway to Independence grant from the National Institutes of Health.

Her research uses human neuroimaging and behavioral measures to examine the neural bases of early language learning in infants and young children. The goal of her research is to develop therapies and interventions to help promote language learning outcomes in children at-risk for learning disabilities. Currently, she directs an NIH-funded clinical trial that will use diffusion MRI to assess whether there are changes in brain structure following a language intervention in the Neonatal Intensive Care Unit for preterm infants.

Academic Appointments


Honors & Awards


  • Young Investigator Award, Society for Developmental and Behavioral Pediatrics (2014-2015)
  • Fine Science Tools Abstract Award, University of California, San Diego (2010)
  • Honorable Mention Graduate Research Fellowship Program, National Science Foundation (2007)
  • Post-baccalaureate Internship Training Award, National Institutes of Health (2004-2005)
  • Arnold B Scheibel Neuroscience Award, Colorado College (2003)
  • Distinction in Neuroscience, Colorado College (2003)
  • First Place Research Presentation, Colorado-Wyoming Academy of Sciences (2003)
  • Phi Beta Kappa, Colorado College (2003)
  • Society for Neuroscience Travel Award, Faculty for Undergraduate Neuroscience (2003)

Research & Scholarship

Clinical Trials


  • Listening to Mom in the NICU: Neural, Clinical and Language Outcomes Not Recruiting

    The purpose of this study is to examine whether playing recordings of a mother's voice to her infant while in the hospital nursery is an effective treatment for promoting healthy brain and language development in infants born preterm.

    Stanford is currently not accepting patients for this trial. For more information, please contact Katherine E Travis, PhD, 650-498-7690.

    View full details

Publications

All Publications


  • More than myelin: Probing white matter differences in prematurity with quantitative T1 and diffusion MRI. NeuroImage. Clinical Travis, K. E., Castro, M. R., Berman, S., Dodson, C. K., Mezer, A. A., Ben-Shachar, M., Feldman, H. M. 2019; 22: 101756

    Abstract

    OBJECTIVE: We combined diffusion MRI (dMRI) with quantitative T1 (qT1) relaxometry in a sample of school-aged children born preterm and full term to determine whether reduced fractional anisotropy (FA) within the corpus callosum of the preterm group could be explained by a reduction in myelin content, as indexed by R1 (1/T1) from qT1 scans.METHODS: 8-year-old children born preterm (n?=?29; GA 22-32?weeks) and full term (n?=?24) underwent dMRI and qT1 scans. Four subdivisions of the corpus callosum were segmented in individual native space according to cortical projection zones (occipital, temporal, motor and anterior-frontal). Fractional anisotropy (FA) and R1 were quantified along the tract trajectory of each subdivision and compared across two birth groups.RESULTS: Compared to controls, preterm children demonstrated significantly decreased FA in 3 of 4 analyzed corpus callosum subdivisions (temporal, motor, and anterior frontal segments) and decreased R1 in only 2 of 4 corpus callosum subdivisions (temporal and motor segments). FA and RD were significantly associated with R1 within temporal but not anterior frontal subdivisions of the corpus callosum in the term group; RD correlated with R1 in the anterior subdivision in the preterm group only.CONCLUSIONS: Myelin content, as indexed by R1, drives some but not all of the differences in white matter between preterm and term born children. Other factors, such as axonal diameter and directional coherence, likely contributed to FA differences in the anterior frontal segment of the corpus callosum that were not well explained by R1.

    View details for PubMedID 30901711

  • White matter microstructure and cognitive outcomes in relation to neonatal inflammation in 6-year-old children born preterm. NeuroImage. Clinical Dubner, S. E., Dodson, C. K., Marchman, V. A., Ben-Shachar, M., Feldman, H. M., Travis, K. E. 2019; 23: 101832

    Abstract

    Cognitive outcomes in preterm (PT) children have been associated with microstructural properties of white matter. PT children who experienced neonatal inflammatory conditions have poorer cognitive outcomes than those who did not. The goal of this study was to contrast white matter microstructure and cognitive outcomes after preterm birth in relation to the presence or absence of severe inflammatory conditions in the neonatal period.PT children (n?=?35), born at gestational age 22-32?weeks, were classified as either PT+ (n?=?12) based on a neonatal history of inflammatory conditions, including bronchopulmonary dysplasia, necrotizing enterocolitis or culture positive sepsis, or PT- (n?=?23) based on the absence of the three inflammatory conditions. Full term (FT) children (n?=?43) served as controls. Participants underwent diffusion MRI and cognitive testing (intelligence, reading, and executive function) at age 6?years. The corpus callosum was segmented into 7 regions using deterministic tractography and based on the cortical projection zones of the callosal fibers. Mean fractional anisotropy (FA) and mean diffusivity (MD) were calculated for each segment. General linear models with planned contrasts assessed group differences in FA, MD and cognitive outcomes. Pearson correlations assessed associations of white matter metrics and cognitive outcome measures.FA was significantly lower and MD was significantly higher in PT+ compared to PT- or FT groups in multiple callosal segments, even after adjusting for gestational age. Executive function scores, but not intelligence or reading scores, were less favorable in PT+ than in PT- groups. Among the entire sample, occipital FA was significantly correlated with IQ (r?=?0.25, p?

    View details for PubMedID 31075555

  • White matter microstructure and cognitive outcomes in relation to neonatal inflammation in 6-year-old children born preterm NEUROIMAGE-CLINICAL Dubner, S. E., Dodson, C. K., Marchman, V. A., Ben-Shachar, M., Feldman, H. M., Travis, K. E. 2019; 23
  • More than myelin: Probing white matter differences in prematurity with quantitative T1 and diffusion MRI NEUROIMAGE-CLINICAL Travis, K. E., Castro, M. H., Berman, S., Dodson, C. K., Mezer, A. A., Ben-Shachar, M., Feldman, H. M. 2019; 22
  • Microstructural properties of white matter pathways in relation tosubsequent reading abilities in children: a longitudinal analysis. Brain structure & function Borchers, L. R., Bruckert, L., Dodson, C. K., Travis, K. E., Marchman, V. A., Ben-Shachar, M., Feldman, H. M. 2018

    Abstract

    Microstructural properties of white matter pathways are associated with concurrent reading abilities in children. In this longitudinal study, we asked whether properties of white matter pathways at the onset of learning to read would be associated with reading abilities at older ages. Children (N=37) with a wide range of reading abilities completed standardized measures of language and phonological awareness and diffusion MRI at age 6years. Mean tract-fractional anisotropy (FA) was extracted from reading-related pathways. At age 8, the same children were re-assessed using a standardized reading measure. Using linear regressions, we examined the contribution of tract-FA at age 6 to reading outcome at age 8, beyond known demographic and pre-literacy predictors of reading. Tract-FA of the left arcuate, left and right superior longitudinal fasciculus (SLF), and left inferior cerebellar peduncle (ICP) made unique contributions to reading outcome after consideration of sex and family history of reading delays. Tract-FA of the left and right SLF and left ICP made unique contributions to reading outcome after the addition of pre-literacy skills. Thus, cerebellar and bilateral cortical pathways represented a network associated with subsequent reading abilities. Early white matter properties may be associated with other neuropsychological functions that predict reading or may influence reading development, independent of reading-related abilities. Tract FA at early stages of learning to read may serve as a biomarker of later reading abilities.

    View details for PubMedID 30539288

  • White matter properties associated with pre-reading skills in 6-year-old children born preterm and at term. Developmental medicine and child neurology Dodson, C. K., Travis, K. E., Borchers, L. R., Marchman, V. A., Ben-Shachar, M., Feldman, H. M. 2018

    Abstract

    AIM: To assess associations between white matter properties and pre-reading skills (phonological awareness and receptive and expressive language) in children born preterm and at term at the onset of reading acquisition.METHOD: Six-year-old children born preterm (n=36; gestational age 22-32wks) and at term (n=43) underwent diffusion magnetic resonance imaging and behavioural assessments. Tracts were selected a priori based on findings from a study of 6-year-old children born at term: the left-hemisphere arcuate fasciculus and superior longitudinal fasciculus, and right-hemisphere uncinate fasciculus. Using linear regression, we assessed associations between fractional anisotropy of tracts and phonological awareness and receptive and expressive language scores. We investigated whether associations were moderated by prematurity.RESULTS: Fractional anisotropy of the left-hemisphere arcuate fasciculus contributed unique variance to phonological awareness across birth groups. The association between fractional anisotropy of the right-hemisphere uncinate fasciculus and receptive and expressive language was significantly moderated by prematurity.INTERPRETATION: A left-hemisphere tract was associated with phonological awareness in both birth groups. A right-hemisphere tract was associated with language only in the term group, suggesting that expressive and receptive language is mediated by different white matter pathways in 6-year-old children born preterm. These findings provide novel insights into similarities and differences of the neurobiology of pre-reading skills between children born preterm and at term at reading onset.WHAT THIS PAPER ADDS: White matter properties and pre-reading abilities were associated in children born preterm at the onset of reading. The neurobiology of phonological awareness was similar in children born preterm versus children born at term at 6 years. The neurobiology of language was different in children born preterm versus children born at term at 6 years.

    View details for PubMedID 29722009

  • White matter properties differ in 6-year old Readers and Pre-readers BRAIN STRUCTURE & FUNCTION Travis, K. E., Adams, J. N., Kovachy, V. N., Ben-Shachar, M., Feldman, H. M. 2017; 222 (4): 1685-1703

    Abstract

    Reading, an essential life skill in modern society, is typically learned during childhood. Adults who can read show white matter differences compared to adults who never learned to read. Studies have not established whether children who can read show similar white matter differences compared to children who cannot read. We compared 6-year old children who could decode written English words and pseudowords (n = 31; Readers) and 6-year old children who could not decode pseudowords and had a standard score <100 on a task for reading single words (n = 11; Pre-readers). We employed diffusion MRI and tractography to extract fractional anisotropy (FA) along the trajectory of six bilateral intra-hemispheric tracts and two posterior subdivisions of the corpus callosum. Readers demonstrated significantly increased FA within the left anterior segment of the superior longitudinal fasciculus (aSLF-L) and the right uncinate fasciculus (UF-R) compared to Pre-readers. FA in the aSLF-L was significantly correlated with phonological awareness; FA in the UF-R was significantly correlated with language. Correlations in the UF-R but not the aSLF-L remained significant after controlling for reading ability, revealing that UF-R group differences were related to both children's language and reading abilities. Taken together, these findings demonstrate new evidence showing that individual differences in white matter structure relate to whether children have begun to read.

    View details for DOI 10.1007/s00429-016-1302-1

    View details for Web of Science ID 000400186400010

  • White matter properties differ in 6-year old Readers and Pre-readers. Brain structure & function Travis, K. E., Adams, J. N., Kovachy, V. N., Ben-Shachar, M., Feldman, H. M. 2016: -?

    Abstract

    Reading, an essential life skill in modern society, is typically learned during childhood. Adults who can read show white matter differences compared to adults who never learned to read. Studies have not established whether children who can read show similar white matter differences compared to children who cannot read. We compared 6-year old children who could decode written English words and pseudowords (n = 31; Readers) and 6-year old children who could not decode pseudowords and had a standard score <100 on a task for reading single words (n = 11; Pre-readers). We employed diffusion MRI and tractography to extract fractional anisotropy (FA) along the trajectory of six bilateral intra-hemispheric tracts and two posterior subdivisions of the corpus callosum. Readers demonstrated significantly increased FA within the left anterior segment of the superior longitudinal fasciculus (aSLF-L) and the right uncinate fasciculus (UF-R) compared to Pre-readers. FA in the aSLF-L was significantly correlated with phonological awareness; FA in the UF-R was significantly correlated with language. Correlations in the UF-R but not the aSLF-L remained significant after controlling for reading ability, revealing that UF-R group differences were related to both children's language and reading abilities. Taken together, these findings demonstrate new evidence showing that individual differences in white matter structure relate to whether children have begun to read.

    View details for PubMedID 27631434

  • Case Series: Fractional Anisotropy Profiles of the Cerebellar Peduncles in Adolescents Born Preterm With Ventricular Dilation JOURNAL OF CHILD NEUROLOGY Travis, K. E., Leitner, Y., Ben-Shachar, M., Yeom, K. W., Feldman, H. M. 2016; 31 (3): 321-327

    Abstract

    This case series assesses white matter microstructure of the cerebellar peduncles in 4 adolescents born preterm with enlarged ventricles and reduced white matter volume in the cerebrum but no apparent injury to the cerebellum. Subjects (ages 12-17 years, gestational age 26-32 weeks, birth weight 825-2211 g) were compared to a normative sample of 19 full-term controls (9-17 years, mean gestational age 39 weeks, mean birth weight 3154 g). Tract profiles for each of the cerebellar peduncles were generated by calculating fractional anisotropy at 30 points along the central portion of each tract. One or more case subjects exhibited higher fractional anisotropy beyond the 90th percentile in the inferior, middle, and superior cerebellar peduncles. Findings demonstrate that differences in cerebellar white matter microstructure can be detected in the absence of macrostructural cerebellar abnormalities.

    View details for DOI 10.1177/0883073815592223

    View details for PubMedID 26116381

  • Variations in the neurobiology of reading in children and adolescents born full term and preterm NEUROIMAGE-CLINICAL Travis, K. E., Ben-Shachar, M., Myall, N. J., Feldman, H. M. 2016; 11: 555-565

    Abstract

    Diffusion properties of white matter tracts have been associated with individual differences in reading. Individuals born preterm are at risk of injury to white matter. In this study we compared the associations between diffusion properties of white matter and reading skills in children and adolescents born full term and preterm. 45 participants, aged 9-17 years, included 26 preterms (born < 36 weeks' gestation) and 19 full-terms. Tract fractional anisotropy (FA) profiles were generated for five bilateral white matter tracts previously associated with reading: anterior superior longitudinal fasciculus (aSLF), arcuate fasciculus (Arc), corticospinal tract (CST), uncinate fasciculus (UF) and inferior longitudinal fasciculus (ILF). Mean scores on reading for the two groups were in the normal range and were not statistically different. In both groups, FA was associated with measures of single word reading and comprehension in the aSLF, AF, CST, and UF. However, correlations were negative in the full term group and positive in the preterm group. These results demonstrate variations in the neurobiology of reading in children born full term and preterm despite comparable reading skills. Findings suggest that efficient information exchange required for strong reading abilities may be accomplished via a different balance of neurobiological mechanisms in different groups of readers.

    View details for DOI 10.1016/j.nicl.2016.04.003

    View details for PubMedID 27158588

  • Tract Profiles of the Cerebellar White Matter Pathways in Children and Adolescents CEREBELLUM Leitner, Y., Travis, K. E., Ben-Shachar, M., Yeom, K. W., Feldman, H. M. 2015; 14 (6): 613-623

    Abstract

    Intact development of cerebellar connectivity is essential for healthy neuromotor and neurocognitive development. To date, limited knowledge about the microstructural properties of the cerebellar peduncles, the major white matter tracts of the cerebellum, is available for children and adolescents. Such information would be useful as a comparison for studies of normal development, clinical conditions, or associations of cerebellar structures with cognitive and motor functions. The goal of the present study was to evaluate the variability in diffusion measures of the cerebellar peduncles within individuals and within a normative sample of healthy children. Participants were 19 healthy children and adolescents, aged 9-17 years, mean age 13.0?±?2.3. We analyzed diffusion magnetic resonance imaging (dMRI) data with deterministic tractography. We generated tract profiles for each of the cerebellar peduncles by extracting four diffusion properties (fractional anisotropy (FA) and mean, radial, and axial diffusivity) at 30 equidistant points along each tract. We were able to identify the middle cerebellar peduncle and the bilateral inferior and superior cerebellar peduncles in all participants. The results showed that within each of the peduncles, the diffusion properties varied along the trajectory of the tracts. However, the tracts showed consistent patterns of variation across individuals; the coefficient of variation for FA across individual profiles was low (?20 %) for each tract. We observed no systematic variation of the diffusion properties with age. These cerebellar tract profiles of the cerebellar peduncles can serve as a reference for future studies of children across the age range and for children and adolescents with clinical conditions that affect the cerebellum.

    View details for DOI 10.1007/s12311-015-0652-1

    View details for PubMedID 25648754

  • Cerebellar White Matter Pathways are Associated With Reading Skills in Children and Adolescents HUMAN BRAIN MAPPING Travis, K. E., Leitner, Y., Feldman, H. M., Ben-Shachar, M. 2015; 36 (4): 1536-1553

    Abstract

    Reading is a critical life skill in the modern world. The neural basis of reading incorporates a distributed network of cortical areas and their white matter connections. The cerebellum has also been implicated in reading and reading disabilities. However, little is known about the contribution of cerebellar white matter pathways to major component skills of reading. We used diffusion magnetic resonance imaging (dMRI) with tractography to identify the cerebellar peduncles in a group of 9- to 17-year-old children and adolescents born full term (FT, n?=?19) or preterm (PT, n?=?26). In this cohort, no significant differences were found between fractional anisotropy (FA) measures of the peduncles in the PT and FT groups. FA of the cerebellar peduncles correlated significantly with measures of decoding and reading comprehension in the combined sample of FT and PT subjects. Correlations were negative in the superior and inferior cerebellar peduncles and positive in the middle cerebellar peduncle. Additional analyses revealed that FT and PT groups demonstrated similar patterns of reading associations within the left superior cerebellar peduncle, middle cerebellar peduncle, and left inferior cerebellar peduncle. Partial correlation analyses showed that distinct sub-skills of reading were associated with FA in segments of different cerebellar peduncles. Overall, the present findings are the first to document associations of microstructure of the cerebellar peduncles and the component skills of reading. Hum Brain Mapp, 2014. © 2014 Wiley Periodicals, Inc.

    View details for DOI 10.1002/hbm.22721

    View details for PubMedID 25504986

  • Decreased and Increased Anisotropy along Major Cerebral White Matter Tracts in Preterm Children and Adolescents PLoS One Travis, K. E., Adams, J. N., Ben-Shachar, M., Feldman, H. M. 2015
  • Decreased and Increased Anisotropy along Major Cerebral White Matter Tracts in Preterm Children and Adolescents. PloS one Travis, K. E., Adams, J. N., Ben-Shachar, M., Feldman, H. M. 2015; 10 (11): e0142860

    Abstract

    Premature birth is highly prevalent and associated with neurodevelopmental delays and disorders. Adverse outcomes, particularly in children born before 32 weeks of gestation, have been attributed in large part to white matter injuries, often found in periventricular regions using conventional imaging. To date, tractography studies of white matter pathways in children and adolescents born preterm have evaluated only a limited number of tracts simultaneously. The current study compares diffusion properties along 18 major cerebral white matter pathways in children and adolescents born preterm (n = 27) and full term (n = 19), using diffusion magnetic resonance imaging and tractography. We found that compared to the full term group, the preterm group had significantly decreased FA in segments of the bilateral uncinate fasciculus and anterior segments of the right inferior fronto-occipital fasciculus. Additionally, the preterm group had significantly increased FA in segments of the right and left anterior thalamic radiations, posterior segments of the right inferior fronto-occipital fasciculus, and the right and left inferior longitudinal fasciculus. Increased FA in the preterm group was generally associated with decreased radial diffusivity. These findings indicate that prematurity-related white matter differences in later childhood and adolescence do not affect all tracts in the periventricular zone and can involve both decreased and increased FA. Differences in the patterns of radial diffusivity and axial diffusivity suggest that the tissue properties underlying group FA differences may vary within and across white matter tracts. Distinctive diffusion properties may relate to variations in the timing of injury in the neonatal period, extent of white matter dysmaturity and/or compensatory processes in childhood.

    View details for DOI 10.1371/journal.pone.0142860

    View details for PubMedID 26560745

  • Abnormal white matter properties in adolescent girls with anorexia nervosa. NeuroImage. Clinical Travis, K. E., Golden, N. H., Feldman, H. M., Solomon, M., Nguyen, J., Mezer, A., Yeatman, J. D., Dougherty, R. F. 2015; 9: 648-659

    Abstract

    Anorexia nervosa (AN) is a serious eating disorder that typically emerges during adolescence and occurs most frequently in females. To date, very few studies have investigated the possible impact of AN on white matter tissue properties during adolescence, when white matter is still developing. The present study evaluated white matter tissue properties in adolescent girls with AN using diffusion MRI with tractography and T1 relaxometry to measure R1 (1/T1), an index of myelin content. Fifteen adolescent girls with AN (mean age = 16.6 years ± 1.4) were compared to fifteen age-matched girls with normal weight and eating behaviors (mean age = 17.1 years ± 1.3). We identified and segmented 9 bilateral cerebral tracts (18) and 8 callosal fiber tracts in each participant's brain (26 total). Tract profiles were generated by computing measures for fractional anisotropy (FA) and R1 along the trajectory of each tract. Compared to controls, FA in the AN group was significantly decreased in 4 of 26 white matter tracts and significantly increased in 2 of 26 white matter tracts. R1 was significantly decreased in the AN group compared to controls in 11 of 26 white matter tracts. Reduced FA in combination with reduced R1 suggests that the observed white matter differences in AN are likely due to reductions in myelin content. For the majority of tracts, group differences in FA and R1 did not occur within the same tract. The present findings have important implications for understanding the neurobiological factors underlying white matter changes associated with AN and invite further investigations examining associations between white matter properties and specific physiological, cognitive, social, or emotional functions affected in AN.

    View details for DOI 10.1016/j.nicl.2015.10.008

    View details for PubMedID 26740918

  • Spatiotemporal Neural Dynamics of Word Understanding in 12- to 18-Month-Old-Infants CEREBRAL CORTEX Travis, K. E., Leonard, M. K., Brown, T. T., Hagler, D. J., Curran, M., Dale, A. M., Elman, J. L., Halgren, E. 2011; 21 (8): 1832-1839

    Abstract

    Learning words is central in human development. However, lacking clear evidence for how or where language is processed in the developing brain, it is unknown whether these processes are similar in infants and adults. Here, we use magnetoencephalography in combination with high-resolution structural magnetic resonance imaging to noninvasively estimate the spatiotemporal distribution of word-selective brain activity in 12- to 18-month-old infants. Infants watched pictures of common objects and listened to words that they understood. A subset of these infants also listened to familiar words compared with sensory control sounds. In both experiments, words evoked a characteristic event-related brain response peaking ?400 ms after word onset, which localized to left frontotemporal cortices. In adults, this activity, termed the N400m, is associated with lexico-semantic encoding. Like adults, we find that the amplitude of the infant N400m is also modulated by semantic priming, being reduced to words preceded by a semantically related picture. These findings suggest that similar left frontotemporal areas are used for encoding lexico-semantic information throughout the life span, from the earliest stages of word learning. Furthermore, this ontogenetic consistency implies that the neurophysiological processes underlying the N400m may be important both for understanding already known words and for learning new words.

    View details for DOI 10.1093/cercor/bhq259

    View details for Web of Science ID 000293076300012

    View details for PubMedID 21209121

  • Age-Dependent White Matter Characteristics of the Cerebellar Peduncles from Infancy Through Adolescence CEREBELLUM Bruckert, L., Shpanskaya, K., McKenna, E. S., Borchers, L. R., Yablonski, M., Blecher, T., Ben-Shachar, M., Travis, K. E., Feldman, H. M., Yeom, K. W. 2019; 18 (3): 372?87
  • White Matter Plasticity in Reading-Related Pathways Differs in Children Born Preterm and at Term: A Longitudinal Analysis FRONTIERS IN HUMAN NEUROSCIENCE Bruckert, L., Borchers, L. R., Dodson, C. K., Marchman, V. A., Travis, K. E., Ben-Shachar, M., Feldman, H. M. 2019; 13
  • Predicting text reading skills at age 8 years in children born preterm and at term EARLY HUMAN DEVELOPMENT Borchers, L. R., Bruckert, L., Travis, K. E., Dodson, C. K., Loe, I. M., Marchman, V. A., Feldman, H. M. 2019; 130: 80?86
  • Predicting text reading skills at age 8?years in children born preterm and at term. Early human development Borchers, L. R., Bruckert, L., Travis, K. E., Dodson, C. K., Loe, I. M., Marchman, V. A., Feldman, H. M. 2019; 130: 80?86

    Abstract

    BACKGROUND: Children born preterm are at risk for developing reading difficulties and for decrements in other cognitive skills compared to children born at term.AIMS: To assess how domains of function, often negatively impacted by preterm birth, predict reading development in children born preterm and at term.STUDY DESIGN: Longitudinal descriptive cohort study.SUBJECTS: Preterm (n?=?48; gestational age 22-32?weeks, 30 males) and term (n?=?41, 18 males) participants were assessed at age 6?years on a battery of verbal and non-verbal cognitive skills and reassessed at age 8 using the Gray Oral Reading Tests-5. Linear regressions assessed the contributions of phonological awareness, language, executive function, and non-verbal IQ at age 6 to reading outcome at age 8.RESULTS: Children born preterm had lower scores than children born at term on all measures (Cohen's d from 0.46 to 1.08, all p?

    View details for PubMedID 30708270

  • Age-Dependent White Matter Characteristics of the Cerebellar Peduncles from Infancy Through Adolescence. Cerebellum (London, England) Bruckert, L., Shpanskaya, K., McKenna, E. S., Borchers, L. R., Yablonski, M., Blecher, T., Ben-Shachar, M., Travis, K. E., Feldman, H. M., Yeom, K. W. 2019

    Abstract

    Cerebellum-cerebrum connections are essential for many motor and cognitive functions and cerebellar disorders are prevalent in childhood. The middle (MCP), inferior (ICP), and superior cerebellar peduncles (SCP) are the major white matter pathways that permit communication between the cerebellum and the cerebrum. Knowledge about the microstructural properties of these cerebellar peduncles across childhood is limited. Here, we report on a diffusion magnetic resonance imaging tractography study to describe age-dependent characteristics of the cerebellar peduncles in a cross-sectional sample of infants, children, and adolescents from newborn to 17years of age (N=113). Scans were collected as part of clinical care; participants were restricted to those whose scans showed no abnormal findings and whose history and exam had no risk factors for cerebellar abnormalities. A novel automated tractography protocol was applied. Results showed that mean tract-FA increased, while mean tract-MD decreased from infancy to adolescence in all peduncles. Rapid changes were observed in both diffusion measures in the first 24months of life, followed by gradual change at older ages. The shape of the tract profiles was similar across ages for all peduncles. These data are the first to characterize the variability of diffusion properties both across and within cerebellar white matter pathways that occur from birth through later adolescence. The data represent a rich normative data set against which white matter alterations seen in children with posterior fossa conditions can be compared. Ultimately, the data will facilitate the identification of sensitive biomarkers of cerebellar abnormalities.

    View details for PubMedID 30637673

  • White Matter Plasticity in Reading-Related Pathways Differs in Children Born Preterm and at Term: A Longitudinal Analysis. Frontiers in human neuroscience Bruckert, L., Borchers, L. R., Dodson, C. K., Marchman, V. A., Travis, K. E., Ben-Shachar, M., Feldman, H. M. 2019; 13: 139

    Abstract

    Children born preterm (PT) are at risk for white matter injuries based on complications of prematurity. They learn to read but on average perform below peers born full term (FT). Studies have yet to establish whether properties of white matter pathways at the onset of learning to read are associated with individual variation later in reading development in PT children. Here, we asked whether fractional anisotropy (FA) at age 6 years is associated with reading outcome at age 8 years in PT children in the same pathways as previously demonstrated in a sample of FT children. PT (n = 34, mean gestational age = 29.5 weeks) and FT children (n = 37) completed diffusion MRI and standardized measures of non-verbal IQ, language, and phonological awareness at age 6 years. Reading skills were assessed at age 8 years. Mean tract-FA was extracted from pathways that predicted reading outcome in children born FT: left arcuate fasciculus (Arc), bilateral superior longitudinal fasciculus (SLF), and left inferior cerebellar peduncle (ICP). We explored associations in additional pathways in the PT children: bilateral inferior fronto-occipital fasciculus, inferior longitudinal fasciculus, and uncinate fasciculus. Linear regression models examined whether the prediction of reading outcome at age 8 years based on mean tract-FA at age 6 years was moderated by birth group. Children born PT and FT did not differ significantly in tract-FA at age 6 years or in reading at age 8 years. Sex, socioeconomic status, and non-verbal IQ at age 6 years were associated with reading outcome and were included as covariates in all models. Birth group status significantly moderated associations between reading outcome and mean tract-FA only in the left Arc, right SLF, and left ICP, before and after consideration of pre-literacy skills. Microstructural properties of these cerebral and cerebellar pathways predicted later reading outcome in FT but not in PT children. Children born PT may rely on alternative pathways to achieve fluent reading. These findings have implications for plasticity of neural organization after early white matter injury.

    View details for DOI 10.3389/fnhum.2019.00139

    View details for PubMedID 31139064

    View details for PubMedCentralID PMC6519445

  • White matter microstructure of 6-year old children born preterm and full term NEUROIMAGE-CLINICAL Dodson, C. K., Travis, K. E., Ben-Shachar, M., Feldman, H. M. 2017; 16: 268?75

    Abstract

    We previously observed a complex pattern of differences in white matter (WM) microstructure between preterm-born (PT) and full-term-born (FT) children and adolescents age 9-17 years. The aim of this study was to determine if the same differences exist as early as age 6 years.We obtained diffusion MRI (dMRI) scans in children born PT at age 6 years (n = 20; 11 males) and FT (n = 38; 14 males), using two scanning protocols: 30 diffusion directions (b = 1000 s/mm2) and 96 diffusion directions (b = 2500 s/mm2). We used deterministic tractography and analyzed fractional anisotropy (FA) along bilateral cerebral WM pathways that demonstrated differences in the older sample.Compared to the FT group, the PT group showed (1) significantly decreased FA in the uncinate fasciculi and forceps major and (2) significantly increased FA in the right anterior thalamic radiation, inferior fronto-occipital fasciculi, and inferior longitudinal fasciculi. This pattern of group differences resembles findings in the previous study of older PT and FT participants. Group differences were similar across dMRI acquisition protocols.The underlying neurobiology driving the pattern of PT-FT differences in FA is present as early as age 6 years. Generalization across dMRI acquisition protocols demonstrates the robustness of group differences in FA. Future studies will use quantitative neuroimaging techniques to understand the tissue properties that give rise to this consistent pattern of WM differences after PT birth.

    View details for PubMedID 28840098

  • Abnormal white matter properties in adolescent girls with anorexia nervosa Neuroimage:Clinical Travis, K. E., Golden, N. H., Feldman, H. M., Solomon, M., Nguyen, J., Mezer, A., Yeatman, J. D., Dougherty, R. F. 2015
  • Abnormal white matter properties in adolescent girls with anorexia nervosa NEUROIMAGE-CLINICAL Travis, K. E., Golden, N. H., Feldman, H. M., Solomon, M., Jenny Nguyen, J., Mezer, A., Yeatman, J. D., Dougherty, R. F. 2015; 9: 648-659

    Abstract

    Anorexia nervosa (AN) is a serious eating disorder that typically emerges during adolescence and occurs most frequently in females. To date, very few studies have investigated the possible impact of AN on white matter tissue properties during adolescence, when white matter is still developing. The present study evaluated white matter tissue properties in adolescent girls with AN using diffusion MRI with tractography and T1 relaxometry to measure R1 (1/T1), an index of myelin content. Fifteen adolescent girls with AN (mean age = 16.6 years ± 1.4) were compared to fifteen age-matched girls with normal weight and eating behaviors (mean age = 17.1 years ± 1.3). We identified and segmented 9 bilateral cerebral tracts (18) and 8 callosal fiber tracts in each participant's brain (26 total). Tract profiles were generated by computing measures for fractional anisotropy (FA) and R1 along the trajectory of each tract. Compared to controls, FA in the AN group was significantly decreased in 4 of 26 white matter tracts and significantly increased in 2 of 26 white matter tracts. R1 was significantly decreased in the AN group compared to controls in 11 of 26 white matter tracts. Reduced FA in combination with reduced R1 suggests that the observed white matter differences in AN are likely due to reductions in myelin content. For the majority of tracts, group differences in FA and R1 did not occur within the same tract. The present findings have important implications for understanding the neurobiological factors underlying white matter changes associated with AN and invite further investigations examining associations between white matter properties and specific physiological, cognitive, social, or emotional functions affected in AN.

    View details for DOI 10.1016/j.nicl.2015.10.008

    View details for Web of Science ID 000373188400069

  • Speech-Specific Tuning of Neurons in Human Superior Temporal Gyrus CEREBRAL CORTEX Chan, A. M., Dykstra, A. R., Jayaram, V., Leonard, M. K., Travis, K. E., Gygi, B., Baker, J. M., Eskandar, E., Hochberg, L. R., Halgren, E., Cash, S. S. 2014; 24 (10): 2679-2693

    Abstract

    How the brain extracts words from auditory signals is an unanswered question. We recorded approximately 150 single and multi-units from the left anterior superior temporal gyrus of a patient during multiple auditory experiments. Against low background activity, 45% of units robustly fired to particular spoken words with little or no response to pure tones, noise-vocoded speech, or environmental sounds. Many units were tuned to complex but specific sets of phonemes, which were influenced by local context but invariant to speaker, and suppressed during self-produced speech. The firing of several units to specific visual letters was correlated with their response to the corresponding auditory phonemes, providing the first direct neural evidence for phonological recoding during reading. Maximal decoding of individual phonemes and words identities was attained using firing rates from approximately 5 neurons within 200 ms after word onset. Thus, neurons in human superior temporal gyrus use sparse spatially organized population encoding of complex acoustic-phonetic features to help recognize auditory and visual words.

    View details for DOI 10.1093/cercor/bht127

    View details for Web of Science ID 000343408200014

    View details for PubMedID 23680841

  • Age-related Changes in Tissue Signal Properties Within Cortical Areas Important for Word Understanding in 12-to 19-Month-Old Infants CEREBRAL CORTEX Travis, K. E., Curran, M. M., Torres, C., Leonard, M. K., Brown, T. T., Dale, A. M., Elman, J. L., Halgren, E. 2014; 24 (7): 1948-1955

    Abstract

    Recently, our laboratory has shown that the neural mechanisms for encoding lexico-semantic information in adults operate functionally by 12-18 months of age within left frontotemporal cortices (Travis et al., 2011. Spatiotemporal neural dynamics of word understanding in 12- to 18-month-old-infants. Cereb Cortex. 8:1832-1839). However, there is minimal knowledge of the structural changes that occur within these and other cortical regions important for language development. To identify regional structural changes taking place during this important period in infant development, we examined age-related changes in tissue signal properties of gray matter (GM) and white matter (WM) intensity and contrast. T1-weighted surface-based measures were acquired from 12- to 19-month-old infants and analyzed using a general linear model. Significant age effects were observed for GM and WM intensity and contrast within bilateral inferior lateral and anterovental temporal regions, dorsomedial frontal, and superior parietal cortices. Region of interest (ROI) analyses revealed that GM and WM intensity and contrast significantly increased with age within the same left lateral temporal regions shown to generate lexico-semantic activity in infants and adults. These findings suggest that neurophysiological processes supporting linguistic and cognitive behaviors may develop before cellular and structural maturation is complete within associative cortices. These results have important implications for understanding the neurobiological mechanisms relating structural to functional brain development.

    View details for DOI 10.1093/cercor/bht052

    View details for Web of Science ID 000338110900021

  • Independence of Early Speech Processing from Word Meaning CEREBRAL CORTEX Travis, K. E., Leonard, M. K., Chan, A. M., Torres, C., Sizemore, M. L., Qu, Z., Eskandar, E., Dale, A. M., Elman, J. L., Cash, S. S., Halgren, E. 2013; 23 (10): 2370-2379

    Abstract

    We combined magnetoencephalography (MEG) with magnetic resonance imaging and electrocorticography to separate in anatomy and latency 2 fundamental stages underlying speech comprehension. The first acoustic-phonetic stage is selective for words relative to control stimuli individually matched on acoustic properties. It begins ?60 ms after stimulus onset and is localized to middle superior temporal cortex. It was replicated in another experiment, but is strongly dissociated from the response to tones in the same subjects. Within the same task, semantic priming of the same words by a related picture modulates cortical processing in a broader network, but this does not begin until ?217 ms. The earlier onset of acoustic-phonetic processing compared with lexico-semantic modulation was significant in each individual subject. The MEG source estimates were confirmed with intracranial local field potential and high gamma power responses acquired in 2 additional subjects performing the same task. These recordings further identified sites within superior temporal cortex that responded only to the acoustic-phonetic contrast at short latencies, or the lexico-semantic at long. The independence of the early acoustic-phonetic response from semantic context suggests a limited role for lexical feedback in early speech perception.

    View details for DOI 10.1093/cercor/bhs228

    View details for Web of Science ID 000325760200009

    View details for PubMedID 22875868

  • Signed Words in the Congenitally Deaf Evoke Typical Late Lexicosemantic Responses with No Early Visual Responses in Left Superior Temporal Cortex JOURNAL OF NEUROSCIENCE Leonard, M. K., Ramirez, N. F., Torres, C., Travis, K. E., Hatrak, M., Mayberry, R. I., Halgren, E. 2012; 32 (28): 9700-9705

    Abstract

    Congenitally deaf individuals receive little or no auditory input, and when raised by deaf parents, they acquire sign as their native and primary language. We asked two questions regarding how the deaf brain in humans adapts to sensory deprivation: (1) is meaning extracted and integrated from signs using the same classical left hemisphere frontotemporal network used for speech in hearing individuals, and (2) in deafness, is superior temporal cortex encompassing primary and secondary auditory regions reorganized to receive and process visual sensory information at short latencies? Using MEG constrained by individual cortical anatomy obtained with MRI, we examined an early time window associated with sensory processing and a late time window associated with lexicosemantic integration. We found that sign in deaf individuals and speech in hearing individuals activate a highly similar left frontotemporal network (including superior temporal regions surrounding auditory cortex) during lexicosemantic processing, but only speech in hearing individuals activates auditory regions during sensory processing. Thus, neural systems dedicated to processing high-level linguistic information are used for processing language regardless of modality or hearing status, and we do not find evidence for rewiring of afferent connections from visual systems to auditory cortex.

    View details for DOI 10.1523/JNEUROSCI.1002-12.2012

    View details for Web of Science ID 000306526800027

    View details for PubMedID 22787055

  • Spatial Organization of Neurons in the Frontal Pole Sets Humans Apart from Great Apes CEREBRAL CORTEX Semendeferi, K., Teffer, K., Buxhoeveden, D. P., Park, M. S., Bludau, S., Amunts, K., Travis, K., Buckwalter, J. 2011; 21 (7): 1485-1497

    Abstract

    Few morphological differences have been identified so far that distinguish the human brain from the brains of our closest relatives, the apes. Comparative analyses of the spatial organization of cortical neurons, including minicolumns, can aid our understanding of the functionally relevant aspects of microcircuitry. We measured horizontal spacing distance and gray-level ratio in layer III of 4 regions of human and ape cortex in all 6 living hominoid species: frontal pole (Brodmann area [BA] 10), and primary motor (BA 4), primary somatosensory (BA 3), and primary visual cortex (BA 17). Our results identified significant differences between humans and apes in the frontal pole (BA 10). Within the human brain, there were also significant differences between the frontal pole and 2 of the 3 regions studied (BA 3 and BA 17). Differences between BA 10 and BA 4 were present but did not reach significance. These findings in combination with earlier findings on BA 44 and BA 45 suggest that human brain evolution was likely characterized by an increase in the number and width of minicolumns and the space available for interconnectivity between neurons in the frontal lobe, especially the prefrontal cortex.

    View details for DOI 10.1093/cercor/bhq191

    View details for Web of Science ID 000291750400003

    View details for PubMedID 21098620

  • Language Proficiency Modulates the Recruitment of Non-Classical Language Areas in Bilinguals PLOS ONE Leonard, M. K., Torres, C., Travis, K. E., Brown, T. T., Hagler, D. J., Dale, A. M., Elman, J. L., Halgren, E. 2011; 6 (3)

    Abstract

    Bilingualism provides a unique opportunity for understanding the relative roles of proficiency and order of acquisition in determining how the brain represents language. In a previous study, we combined magnetoencephalography (MEG) and magnetic resonance imaging (MRI) to examine the spatiotemporal dynamics of word processing in a group of Spanish-English bilinguals who were more proficient in their native language. We found that from the earliest stages of lexical processing, words in the second language evoke greater activity in bilateral posterior visual regions, while activity to the native language is largely confined to classical left hemisphere fronto-temporal areas. In the present study, we sought to examine whether these effects relate to language proficiency or order of language acquisition by testing Spanish-English bilingual subjects who had become dominant in their second language. Additionally, we wanted to determine whether activity in bilateral visual regions was related to the presentation of written words in our previous study, so we presented subjects with both written and auditory words. We found greater activity for the less proficient native language in bilateral posterior visual regions for both the visual and auditory modalities, which started during the earliest word encoding stages and continued through lexico-semantic processing. In classical left fronto-temporal regions, the two languages evoked similar activity. Therefore, it is the lack of proficiency rather than secondary acquisition order that determines the recruitment of non-classical areas for word processing.

    View details for DOI 10.1371/journal.pone.0018240

    View details for Web of Science ID 000288811500031

    View details for PubMedID 21455315

  • Spatiotemporal dynamics of bilingual word processing NEUROIMAGE Leonard, M. K., Brown, T. T., Travis, K. E., Gharapetian, L., Hagler, D. J., Dale, A. M., Elman, J. L., Halgren, E. 2010; 49 (4): 3286-3294

    Abstract

    Studies with monolingual adults have identified successive stages occurring in different brain regions for processing single written words. We combined magnetoencephalography and magnetic resonance imaging to compare these stages between the first (L1) and second (L2) languages in bilingual adults. L1 words in a size judgment task evoked a typical left-lateralized sequence of activity first in ventral occipitotemporal cortex (VOT: previously associated with visual word-form encoding) and then ventral frontotemporal regions (associated with lexico-semantic processing). Compared to L1, words in L2 activated right VOT more strongly from approximately 135 ms; this activation was attenuated when words became highly familiar with repetition. At approximately 400 ms, L2 responses were generally later than L1, more bilateral, and included the same lateral occipitotemporal areas as were activated by pictures. We propose that acquiring a language involves the recruitment of right hemisphere and posterior visual areas that are not necessary once fluency is achieved.

    View details for DOI 10.1016/j.neuroimage.2009.12.009

    View details for Web of Science ID 000274064500039

    View details for PubMedID 20004256

  • Somatodendritic Kv7/KCNQ/M channels control interspike interval in hippocampal interneurons JOURNAL OF NEUROSCIENCE Lawrence, J. J., Saraga, F., Churchill, J. F., Statland, J. M., Travis, K. E., Skinner, F. K., McBain, C. J. 2006; 26 (47): 12325-12338

    Abstract

    The M-current (I(M)), comprised of Kv7 channels, is a voltage-activated K+ conductance that plays a key role in the control of cell excitability. In hippocampal principal cells, I(M) controls action potential (AP) accommodation and contributes to the medium-duration afterhyperpolarization, but the role of I(M) in control of interneuron excitability remains unclear. Here, we investigated I(M) in hippocampal stratum oriens (SO) interneurons, both from wild-type and transgenic mice in which green fluorescent protein (GFP) was expressed in somatostatin-containing interneurons. Somatodendritic expression of Kv7.2 or Kv7.3 subunits was colocalized in a subset of GFP+ SO interneurons, corresponding to oriens-lacunosum moleculare (O-LM) cells. Under voltage clamp (VC) conditions at -30 mV, the Kv7 channel antagonists linopirdine/XE-991 abolished the I(M) amplitude present during relaxation from -30 to -50 mV and reduced the holding current (I(hold)). In addition, 0.5 mM tetraethylammonium reduced I(M), suggesting that I(M) was composed of Kv7.2-containing channels. In contrast, the Kv7 channel opener retigabine increased I(M) amplitude and I(hold). When strongly depolarized in VC, the linopirdine-sensitive outward current activated rapidly and comprised up to 20% of the total current. In current-clamp recordings from GFP+ SO cells, linopirdine induced depolarization and increased AP frequency, whereas retigabine induced hyperpolarization and arrested firing. In multicompartment O-LM interneuron models that incorporated I(M), somatodendritic placement of Kv7 channels best reproduced experimentally measured I(M). The models suggest that Kv3- and Kv7-mediated channels both rapidly activate during single APs; however, Kv3 channels control rapid repolarization of the AP, whereas Kv7 channels primarily control the interspike interval.

    View details for DOI 10.1523/JNEUROSCI.3521-06.2006

    View details for Web of Science ID 000242387800026

    View details for PubMedID 17122058

  • Regional dendritic variation in neonatal human cortex: A quantitative Golgi study DEVELOPMENTAL NEUROSCIENCE Travis, K., Ford, K., Jacobs, B. 2005; 27 (5): 277-287

    Abstract

    The present study quantitatively compared the basilar dendritic/spine systems of lamina V pyramidal neurons across four hierarchically arranged regions of neonatal human neocortex. Tissue blocks were removed from four Brodmann's areas (BAs) in the left hemisphere of four neurologically normal neonates (mean age=41+/- 40 days): primary (BA4 and BA3-1-2), unimodal (BA18), and supramodal cortices (BA10). Tissue was stained with a modified rapid Golgi technique. Ten cells per region (N=160) were quantified. Despite the small sample size, significant differences in dendritic/spine extent obtained across cortical regions. Most apparent were substantial differences between BA4 and BA10: total dendritic length was 52% greater in BA4 than BA10, and dendritic spine number was 67% greater in BA4 than BA10. Neonatal patterns were compared to adult patterns, revealing that the relative regional pattern of dendritic complexity in the neonate was roughly the inverse of that established in the adult, with BA10 rather than BA4 being the most complex area in the adult. Overall, regional dendritic patterns suggest that the developmental time course of basilar dendritic systems is heterochronous and is more protracted for supramodal BA10 than for primary or unimodal regions (BA4, BA3-1-2, BA18).

    View details for DOI 10.1159/000086707

    View details for Web of Science ID 000231701800001

    View details for PubMedID 16137985

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