Jed Meltzer

Dr. Jed Meltzer, Ph.D.

Research Focus

I am a cognitive neuroscientist specializing in language, with research interests both in the basic science of language processing from a neurobiological perspective, and in applications to the diagnosis and treatment of acquired neurological disorders such as stroke and dementia.

Google Scholar page:

https://scholar.google.com/citations?user=Qp7qPF8AAAAJ&hl=en

Much of my work has dealt with neural oscillations measured with electroencephalography (EEG) and magnetoencephalography (MEG). These tools offer the ability to track the engagement of various brain networks at high temporal resolution, allowing us to assess the contributions of multiple neural pathways to the processes of language comprehension and production. Furthermore, the electrophysiological signals measured by these technologies are rich in information to address advanced questions beyond "where and when" information is processed in the brain. Specific areas of research interest include:

1) Interhemispheric interactions for language and motor functions. The human brain is functionally asymmetrical, with the left hemisphere playing a dominant role in language and also hand movement, and the right hemisphere exhibiting specialization for spatial processing. However, interaction between the two hemispheres is an essential part of everday functioning, and seems to play an increasingly important role in compensating for functional declines occurring in neurological disease, and also in the normal process of aging. Interhemispheric interaction has been characterized as either cooperative or competitive, and understanding how both kinds of interactions can happen simultaneously is essential to harnessing the therapeutic potential of modulating them. Our laboratory conducts behavioural and neuroimaging (MEG, fMRI) studies of tasks involving interhemispheric transfer of information.

2) Quantifying and modulating dysfunctional neural activity. Although structural brain damage (i.e. death of neurons) is a key feature of both stroke and dementia, many of the behavioural deficits in these disorders may be attributable to subtler forms of damage and dysfunction that are potentially reversible. In recent work, my laboratory has pioneered analyses of resting-state MEG dynamics to localize and quantify dysfunctional activity in brain areas that are affected by disease but still structurally intact. Ongoing work tests whether such dysfunction may be reversible using approaches such as brain stimulation and drugs, resulting in therapeutic improvements. Current brain stimulation experiments involve transcranial magnetic stimulation (TMS) and high-definition transcranial direct current stimulation (HD-TDCS) of areas implicated in language and motor deficits.

3) Harnessing technological advances in language assessment and rehabilitation. Advances in computational linguistics are proving invaluable in both basic and cognitive neuroscience. The use of software to select stimuli for language experiments on quantitative criteria is now commonplace, but many other transformations are underway. For the assessment and treatment of dementia and stroke, our studies used automated analysis of naturalistic language samples to identify patterns of language change associated with normal aging and neurological impariment. These measures, along with the brain imaging measures discussed above, offer the potential to evaluate novel interventions more sensitively, to test whether a given intervention is having a desirable effect in a given individual, early in the intervention process. Additional work concerns the use of advanced technological tools as therapeutic aids in neurorehabilitation, including adult-oriented computer training software incorporating spaced repetition, and speech therapy delivered remotely through telerehabilitation software. 

Publications

Title Source (Journal/Book/Conference) Authors/Presenters Published On Type
Electrophysiological signatures of phonological and semantic maintenance in sentence repetition. Neuroimage Meltzer JA, †Kielar A, Panamsky L, Links K, Deschamps T, Leigh RC 1505707200 Journal Article
Computer-based treatment of post-stroke language disorders: A non-inferiority study of telerehabilitation compared to in-person service delivery. Aphasiology Meltzer JA, Harvey S, Steele R, Baird A 1498881600 Journal Article
White matter disruption and connected speech in non-fluent and semantic variants of primary progressive aphasia. Dementia and Geriatric Cognitive Disorders Extra Marcotte K, Graham NL, Fraser KC, Meltzer JA, Tang-Wai D, Chow TW, Freedman M, Leonard C, Black SE, Rochon E 1488430800 Journal Article
Functional reorganization of language networks for semantics and syntax in chronic stroke: Evidence from MEG. Human Brain Mapping Kielar A, Deschamps T, Jokel R, Meltzer JA 1472702400 Journal Article
Identifying dysfunctional cortex: Dissociable effects of stroke and aging on resting state dynamics in MEG and fMRI. Front Aging Neurosci Kielar A, Deschamps T, Chu RK, Jokel R, Khatamian YB, Chen JJ, Meltzer JA 1456981200 Journal Article
Semantic and phonological contributions to immediate and delayed cued sentence recall. Memory and Cognition Meltzer JA, Rose NS, Panamsky L, Leigh RC, Links KA, Silberberg A, Madani N, Deschamps T 1454302800 Journal Article
Linguistic features identify Alzheimer's disease in narrative speech. Journal of Alzheimer's Disease Fraser KC, Meltzer JA, Rudzicz F 1443672000 Journal Article
(2015). Localization of electrophysiological responses to semantic and syntactic anomalies in language comprehension with MEG Neuroimage Kielar A, Panamsky L, Meltzer JA 1421902800 Journal Article
Age-related changes to oscillatory dynamics in hippocampal and neocortical networks. Neurobiology of learning and memory Rondina R, Olsen RK, McQuiggan DA, Fatima Z, Li L, Oziel E, Meltzer JA, Ryan JD 1420088400 Journal Article
MEG-based detection and localization of electrophysiological slowing in perilesional cortex in chronic stroke. NeuroImage: Clinical Chu R, Braun AR, Meltzer JA 1420088400 Journal Article
Localization of electrophysiological responses to semantic and syntactic anomalies in language comprehension with MEG. NeuroImage Kielar A Panamsky L Links K Meltzer JA 1416459600 Journal Article
Oscillatory responses to semantic and syntactic violations. Journal of Cognitive Neuroscience Kielar A, Meltzer JA, Moreno S, Bialystok E, Alain C 1401854400 Journal Article
Stroke induced reorganization of the neural networks for sentence comprehension, and relationship to perilesional dysfunction revealed by MEG and ASL Frontiers 52nd Annual Meeting of Academy of Aphasia Kielar A, Deschamps T, Chu R K O, Panamsky L, Khatamian Y B, Chen J J, and Meltzer J A 1390366800 Abstract
Hippocampal and Neocortical Oscillatory Contributions to Visuospatial Binding and Comparison. Journal of Experimental Psychology: General Olsen RK, Rondina Ii R, Riggs L, Meltzer JA, Ryan JD 1376280000 Journal Article
Adaptive significance of right hemisphere activation in aphasic language comprehension. Neuropsychologia Meltzer JA, Wagage S, Ryder J, Solomon B, Braun AR 1365220800 Journal Article
P600-like positivity and left anterior negativity responses are elicited by semantic reversibility in nonanomalous sentences. Journal of Neurolinguistics. Meltzer JA, Braun AR 1357016400 Journal Article
Automated classification of primary progressive aphasia subtypes from narrative speech transcripts. Cortex Fraser K, Meltzer JA, Graham NL, Leonard C, Hirst G, Black C, Rochon E 1356066000 Journal Article
Localizing the component processes of lexical access using modern neuroimaging techniques The Mental Lexicon Meltzer JA 1340683200 Journal Article
An EEG-MEG dissociation between online syntactic comprehension and posthoc reanalysis Frontiers in Human Neuroscience Meltzer JA, Braun AR 1296795600 Journal Article
Infraslow EEG oscillations organize large-scale cortical-subcortical interactions during sleep: A combined EEG/fMRI study Brain Research Picchioni D, Horovitz SG, Fukunaga M, Carr WS, Meltzer JA, Balkin TJ, Duyn,JH, Braun AR 1296795600 Journal Article
Neural aspects of sentence comprehension: syntactic complexity, reversibility, and reanalysis. Cerebral Cortex Meltzer JA, McArdle JJ, Schafer RJ, Braun AR 1280635200 Journal Article
Strategies for longitudinal neuroimaging studies of overt language production. NeuroImage Meltzer JA, Postman-Caucheteux WA, McArdle JJ, Braun AR 1250308800 Journal Article
Neural correlates of evaluative compared with passive tasting. European Journal of Neuroscience Bender G, Veldhuizen MG, Meltzer JA, Gitelman DR, Small DM 1247630400 Journal Article
Transverse patterning dissociates human EEG theta power and hippocampal BOLD activation. Psychophysiology Meltzer JA, Fonzo GA, Constable RT 1230786000 Journal Article
Effects of working memory load on oscillatory power in human intracranial EEG. Cerebral Cortex Meltzer JA, Zaveri HP, Goncharova II, Distasio MM, Papademetris X, Spencer SS, Spencer DD, Constable RT 1217563200 Journal Article
Biphasic hemodynamic responses influence deactivation and may mask activation in block-design fMRI paradigms. Human Brain Mapping Meltzer JA, Negishi M, Constable RT 1207022400 Journal Article
Individual differences in EEG theta and alpha dynamics during working memory correlate with fMRI responses across subjects Clinical Neurophysiology Meltzer JA, Negishi M, Mayes LC, Constable RT 1193889600 Journal Article
A functional magnetic resonance imaging study of the long-term influences of early indomethacin exposure on language processing in the brains of prematurely born children. Pediatrics Ment LR, Peterson BS, Meltzer JA, Vohr B, Allan W, Katz KH, Lacadie C, Schneider KC, Duncan CC, Makuch RW, Constable RT 1157083200 Journal Article
Activation of human hippocampal formation reflects success in both encoding and cued recall of paired associates NeuroImage Meltzer JA, Constable RT 1105765200 Journal Article
Temperature dependence of non-linear capacitance in human embryonic kidney cells transfected with prestin, the outer hair cell motor protein Neuroscience Letters Meltzer J, Santos-Sacchi J 989380800 Journal Article

Education

Academic Appointments

  • 2006–2010: Postdoctoral Fellow, Language Section, National Institute on Deafness and Other Communication Disorders, Bethesda, MD
  • 2010–Present: Assistant Professor, Psychology, University of Toronto, Toronto, ON
  • 2010–Present: Assistant Professor, Speech-Language Pathology, University of Toronto, Toronto, ON

Research Projects

External

  • 2012–2014: Characterizing functional lesions in stroke recovery using MEG and MRI.
    Collaborators: Jean Chen

    Sponsors: Heart and Stroke Foundation, 100,000 (CAD)

    Research Grant
  • 2012–2014: Detection of early cortical pathology using MEG and speech analysis.

    Sponsors: Alzheimer's Association, 97.090 (USD)

    Research Grant
  • 2013–2014: Centre for Stroke Recovery Catalyst GRant
    Collaborators: Elizabeth Rochon, Carol Leonard
    Institutions: University of Toronto, University of Ottawa

    Sponsors: Heart and Stroke Foundation, 49,172 (CAD)

    Research Grant
  • 2013–2015: Effects of language experience and education on brain functional connectivity.
    Collaborators: Cheryl Grady, Leticia Mansur, Ricardo Nardini.
    Institutions: University of Toronto, University of São Paulo

    Sponsors: University of Toronto / University of São Paulo Joint Research Program, 39,880 (CAD)

    Research Grant
  • 2014–2018: Individually optimized brain stimulation in dementia using MEG.
    Collaborators: Faranak Farzan, Frank Rudzicz, Regina Jokel
    Institutions: Baycrest, Centre for Addiction and Mental Health, Toronto Rehabilitation Institute

    Sponsors: Ontario Brain Institute, 726,655 (CAD)

    Research Grant
  • 2014–2019: Augmentation of neurorehabilitation training using targeted brain stimulation.
    Collaborators: Asaf Gilboa, Sylvain Moreno
    Institutions: Baycrest

    Sponsors: Canada Foundation for Innovation, 277,791 (CAD)

    Research Grant

Internal

  • 2006–2010:
    Supervisor: Allen Braun
    Institutions: National Institute on Deafness and Other Communication Disorders

    Sponsors: NIH Intramural Postdoctoral Fellowship

Curriculum Vitae

Contact

3560 Bathurst St.
Toronto, ON M6A 2E1 Phone: 416 785 2500 x2117 Email: jmeltzer@research.baycrest.org Fax: 416 785 2862