Jed Meltzer

Dr. Jed Meltzer, Ph.D.

Research Focus

My research deals with the neural mechanisms responsible for understanding and producing language, with an emphasis on multiple partially redundant pathways. The study of multiple pathways for information processing is essential to future developments in stroke rehabilitation, as functional and structural assessments can be made of an individual's capacity to exploit spared pathways to recover cognitive and linguistic abilities. Behavioural intervention strategies could be tailored to an individual's post-stroke neuroanatomical status for maximal effect. Furthermore, physiological interventions such as noninvasive brain stimulation (NIBS) can be targeted and optimized for individuals to bring about the desired recruitment of brain networks to achieve functional restoration and compensation. 

My work has explored the potential of magnetoencephalography (MEG) as a mapping tool in neurolinguistics, providing the spatial and temporal resolution necessary to measure the involvement of specific neural pathways on a time scale relevant to everyday language use. In current work, we are using MEG to evaluate the brain's response to transcranial magnetic stimulation (TMS) and transcranial direct current stimulation (TDCS), two techniques that may help promote beneficial plasticity in recovery from brain injury, but are as yet poorly understood. 

Other behavioural work aims at a closer integration between the fields of cognitive neuroscience and computational linguistics. Assessment of language function in neurological patients has traditionally depended on behavioural tests administered by a trained professional under somewhat artificial conditions. Although these tests provide invaluable information, they do not capture more subtle aspects of variability in language use, especially those associated with milder forms of impairment as present in dementia and traumatic brain injury patients. Recently numerous tools have become available for automated analysis of naturalistic language samples that are easily obtained from patients. Studies have revealed quantifiable aspects of language use associated with normal aging and neurological impairment, but the relationship of these factors to neuroanatomical pathways remains to be explored. Studies in our lab exploit the potential of computational linguistics tools to contribute towards improved diagnosis and treatment of cognitive impairment in stroke and progressive disorders.

Publications

Title Source (Journal/Book/Conference) Authors/Presenters Published On Type
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
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
(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
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