Comparison of subdural and subgaleal recordings of cortical high-gamma activity in humans

Jared D Olson; Jeremiah D Wander; Lise Johnson; Devapratim Sarma; Kurt Weaver; Edward J Novotny; Jeffrey G Ojemann; Felix Darvas

doi:10.1016/j.clinph.2015.03.014

Comparison of subdural and subgaleal recordings of cortical high-gamma activity in humans

Clin Neurophysiol. 2016 Jan;127(1):277-284. doi: 10.1016/j.clinph.2015.03.014. Epub 2015 Apr 9.

Authors

Jared D Olson¹, Jeremiah D Wander², Lise Johnson³, Devapratim Sarma⁴, Kurt Weaver⁵, Edward J Novotny⁶, Jeffrey G Ojemann⁷, Felix Darvas⁸

Affiliations

¹ University of Washington, Department of Rehabilitation Medicine, USA; University of Washington, Center for Sensorimotor Neural Engineering, USA. Electronic address: [email protected].
² University of Washington, Center for Sensorimotor Neural Engineering, USA; University of Washington, Department of Bioengineering, USA. Electronic address: [email protected].
³ University of Washington, Center for Sensorimotor Neural Engineering, USA; University of Washington, Department of Neurological Surgery, USA. Electronic address: [email protected].
⁴ University of Washington, Center for Sensorimotor Neural Engineering, USA; University of Washington, Department of Bioengineering, USA. Electronic address: [email protected].
⁵ University of Washington, Center for Sensorimotor Neural Engineering, USA; University of Washington, Department of Radiology, USA. Electronic address: [email protected].
⁶ University of Washington, Center for Sensorimotor Neural Engineering, USA; University of Washington, Department of Neurology, USA; University of Washington, Department of Pediatrics, USA. Electronic address: [email protected].
⁷ University of Washington, Center for Sensorimotor Neural Engineering, USA; University of Washington, Department of Neurological Surgery, USA; University of Washington, Department of Radiology, USA; University of Washington, Seattle Children's Hospital Division of Neurosurgery, USA. Electronic address: [email protected].
⁸ University of Washington, Center for Sensorimotor Neural Engineering, USA; University of Washington, Department of Neurological Surgery, USA. Electronic address: [email protected].

Abstract

Objective: The purpose of this study is to determine the relationship between cortical electrophysiological (CE) signals recorded from the surface of the brain (subdural electrocorticography, or ECoG) and signals recorded extracranially from the subgaleal (SG) space.

Methods: We simultaneously recorded several hours of continuous ECoG and SG signals from 3 human pediatric subjects, and compared power spectra of signals between a differential SG montage and several differential ECoG montages to determine the nature of the transfer function between them.

Results: We demonstrate the presence of CE signals in the SG montage in the high-gamma range (HG, 70-110 Hz), and the transfer function between 70 and 110 Hz is best characterized as a linear function of frequency. We also test an alternative transfer function, i.e. a single pole filter, to test the hypothesis of frequency dependent attenuation in that range, but find this model to be inferior to the linear model.

Conclusions: Our findings indicate that SG electrodes are capable of recording HG signals without frequency distortion compared with ECoG electrodes.

Significance: HG signals could be recorded minimally invasively from outside the skull, which could be important for clinical care or brain-computer interface applications.

Keywords: Brain computer interface; Electrocorticography; Electroencephalography; High-gamma brain machine interface; Subgaleal.

Publication types

Comparative Study
Research Support, N.I.H., Extramural
Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

Cerebral Cortex / physiology*
Child
Child, Preschool
Electrocorticography / instrumentation
Electrocorticography / methods*
Electrodes, Implanted*
Electroencephalography / methods
Female
Humans
Male
Subdural Space / physiology*

Abstract

Publication types

MeSH terms

Grants and funding