Mapping Cortical Function with Event-Related Electrocorticography

  • Vernon L. TowleEmail author
  • Zhongtian Dai
  • Weili Zheng
  • Naoum P. Issa


Direct cortical stimulation is the current standard for mapping basic motor and sensory function in the surgical setting, and is commonly used to confirm noninvasive functional mapping techniques, such as functional MRI, PET, MEG and transcranial magnetic stimulation studies. This chapter reviews the recent proliferation of event-induced high-frequency (30-250 Hz) electrocorticographic gamma mapping studies. Such studies have expanded the scope of cortical mapping to expressive and receptive speech processing, memory storage and retrieval, and other sensory and motor processes. Such maps can be registered and displayed with MR images and even directly on cortex. Progress toward passively mapping various cognitive and behavioral states outside of the hospital setting using chronically indwelling subdural electrodes that communicate without cables through telemetry is reviewed. This technique still needs validation with clinically accepted functional mapping tests, and will likely soon join the physician’s armamentarium of accepted functional mapping techniques.


Transcranial Magnetic Stimulation Functional Mapping Gamma Activity Uncinate Fasciculus Primary Auditory Cortex 
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Copyright information

© Springer International Publishing Switzerland 2016

Authors and Affiliations

  • Vernon L. Towle
    • 1
    Email author
  • Zhongtian Dai
    • 1
  • Weili Zheng
    • 1
  • Naoum P. Issa
    • 1
  1. 1.Department of NeurologyUniversity of Chicago Medical SchoolChicagoUSA

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