About

Professor Shadi A. Dayeh is a faculty member and Principal Investigator/Director for the Integrated Electronics and Biointerfaces Laboratory (IEBL) at UC San Diego. His research focuses on novel and clinical devices for interfacing with the brain and spine, as well as gallium nitride materials and devices. Under his leadership, the laboratory pursues advancements in neural interfaces, including high-resolution electrocorticography (ECoG) and combined ECoG and LED microdisplay technologies. The lab also explores the development of spinal cord implants and multimodal neural interface devices for the central nervous system. Professor Dayeh's work integrates materials science, device engineering, and biointerfaces to create innovative solutions for neurological applications.

Research topics

• Chemistry
• Computer Science
• Materials science
• Nanotechnology
• Crystallography
• Optoelectronics
• Artificial Intelligence
• Geology
• Aerospace engineering
• Control engineering
• Inorganic chemistry
• Engineering
• Remote sensing

Selected publications

• 429 Microelectrophysiologic Mapping of the Visual System in Preparation for Whole Eye Transplant: Circumferential Recordings of the Optic Nerve and High-Density Surface Recordings of Early Visual Cortex

  Neurosurgery · 2026-03-26

  articleSenior author
  PublisherDOI

• Stimulation acts to uncover microscale pathological changes induced by brain tumors

  Brain stimulation · 2025-01-01

  articleOpen access

  mentalizing network connectivity following iTBS (d0.53),but not 10 Hz rTMS (d0.07),versus sham.Little change was seen in mentalizingsimulation connectivity when comparing iTBS and 10 Hz rTMS to sham.Pain scores were low in all groups (means <5/10) and drop-out rates did not differ across groups.Conclusions: This study marks the first investigation of rTMS effects on social cognitive circuitry in SSDs, incorporating individualized targeting approaches.Our results suggest that iTBS can change mentalizing network connectivity with medium effect size.We are now embarking on a larger clinical trial using iTBS versus sham to assess changes in social cognitive performance.

  PublisherOA PDFDOI

• A Scalable Fishbone Nanowire Array (FINE) for 3D Quasi‐Intracellular Recording in Intact Brains

  Advanced Materials · 2025-07-23 · 2 citations

  articleSenior authorCorresponding

  Intracellular recordings provide unique access to the submillisecond neuronal membrane potential changes, revealing dynamics that orchestrate cellular, local, and large-scale brain activity. However, technical requirements limit the scalability of intracellular recordings to large populations of neurons, especially within intact brains. To overcome this limitation, a Fishbone Intracellular Nanowire Electrode (FINE) is developed with ultra-sharp nanowire tips strategically integrated at slanted angles along an implantable shank to record 3D intracellular potentials from ensembles of neurons in intact brain. A novel fabrication process is developed to integrate reverse-angled platinum silicide (PtSi) nanowires to preserve the structural integrity of FINE during insertion. As-implanted or sub-micron retraced FINE spreads the PtSi nanowires away from the shank to establish intimate nanowire-neuron interfaces that yield quasi-intracellular potentials. Comparative analyses of nanowire recordings versus adjacent planar recordings on the same shank validate their distinctive quasi-intracellular recording characteristics. The scalability of FINE is demonstrated to a 3D 24-shank array with 594 nanowires and 430 planar contacts and successfully identified quasi-intracellular potentials across 127 distinct nanowires in the intact brain. FINE's 3D quasi-intracellular recording holds the potential to unlock detailed investigations of the intricate ionic potential fluctuations and patterns of transmembrane potentials that drive behavior and cognition.

  PublisherDOI

• A TDMA Neural Recording SoC With IIR-RLS Adaptive Filters for 83.4 dB Artifact Suppression Across 256 Channels

  IEEE Journal of Solid-State Circuits · 2025-04-30

  article

  This article introduces a digitally-assisted, multi-electrode neural recording system equipped with a multi-channel stimulation artifact canceller (SAC) module. The system employs a 16-electrode time division multiple access (TDMA) scheme, allowing multiplexed neural signals to be recorded through a single shared analog front end (AFE). Simultaneously, it cancels stimulation artifacts from 16 stimulation electrodes using an infinite impulse response (IIR) recursive least squares (RLS) adaptive filter (AF). The proposed system-on-chip (SoC) is validated in vitro, demonstrating an instantaneous, real-time suppression of 100 mV stimulation artifacts by 83.4 dB, with rapid AF calibration convergence times under 5.1 s for 256 channel transfer function (TF) combinations. Fabricated using a 65 nm process, each recording electrode AFE occupies 0.0018 mm<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup>, achieves an input-referred noise of 4.9/4.8 μVrms for local field potential (LFP) and action potential (AP) bands respectively, and consumes 5.8 μW in recording mode. The SAC module consumes 2.9 μW/TF and minimally impacts recording signal-to-noise and distortion ratio (SNDR) by 0.8 dB. This results in a high-performing SAC chip, optimized for energy and area efficiency.

  PublisherDOI

• Electrocorticography microdisplay for high precision intraoperative brain mapping

  Brain stimulation · 2025-01-01

  articleOpen accessSenior author
  PublisherOA PDFDOI

• Graphene-polymer nanofibers enable optically induced electrical responses in stem cell-derived electrically excitable cells and brain organoids

  Biomaterials · 2025-05-21 · 6 citations

  articleOpen access
  PublisherOA PDFDOI

• CNSC-33. ELECTROPHYSIOLOGIC SIGNATURES OF TUMOR INFILTRATION ACROSS GLIOMA SUBTYPES ON INTRACRANIAL EEG

  Neuro-Oncology · 2025-11-01

  article

  Abstract Pioneering work in cancer neuroscience revealed that glioma development and infiltration occur in part via novel, functional neuronal-tumor synapses. Resultant hyperexcitability, which perpetuates disease progression, can be detected using standard and high resolution electrophysiology techniques. However, differences across glioma subtypes and the topographic distribution of these alterations are not well characterized in existing literature. To interrogate these perturbations and their extent, we obtained intraoperative intracranial electrophysiology recordings in 72 patients (n=23 IDH-wildtype glioma, 15 IDH-mutant glioma, 28 non-tumor epilepsy cases, and 6 movement disorder cases) using standard (e.g., 6-8 contacts) clinical electrodes (ECoG, n=40), microelectrodes with 128-1024 channels that conform to the brain surface (n=46), and Neuropixels probes (n=29). All recordings were from the frontal, temporal, or parietal lobe. Electrode location relative to the enhancing tumor and associated T2 hyperintensity was determined using a 3D localization pipeline, coregistered to segmented pre-operative imaging. Endpoints include spectral power band analysis with modeling of periodic and aperiodic components and interictal discharge rates (IIDs). Euclidean and geodesic distance, with the latter following anatomic geography, to the enhancing tumor boundary was calculated per participant and channel. Clinical ECoG grids did not discriminate regional or overall differences in high gamma power (HGP), aperiodic (E/I) slope or exponent, or IIDs. However, using high resolution grids, increasing geodesic distance was associated with a linear decrease in high gamma power for both IDH-mutant and -wildtype glioma cases. Similarly, the E/I slope of 30-50 Hz activity increased linearly with distance from tumor boundary, implicating a relative shift toward peritumoral excitatory activity. IDH-wildtype glioma was associated with the highest HGP and IID rate, and geodesic distance was most precise in distinguishing region differences; both distance calculations were relevant for IDH-mutant tumors. Comparison to non-tumor cases highlighted mechanistic similarities across neurologic diseases that may be identifiable using neuroelectrical signatures.

  PublisherDOI

• The Conformal, High‐Density SpineWrap Microelectrode Array for Focal Stimulation and Selective Muscle Recruitment

  Advanced Functional Materials · 2025-01-08 · 2 citations

  articleOpen accessSenior authorCorresponding

  Epidural electrical stimulation (EES) of the spinal cord is widely applied for pain management and has garnered considerable interest as a possible route to functional restoration after spinal cord injury. Currently, EES employs bulky, non-conformal paddle arrays with low channel counts. This limits stimulation effectiveness by requiring high stimulation currents, reduces selectivity of muscle recruitment, and requires subject-specific designs to accommodate varied neuroanatomy across the patient population. Here, we report on a thin-film, high-channel count microelectrode array, termed SpineWrap, which wraps around the dorsolateral aspect of the rat spinal cord. SpineWrap delivers focal stimulation to selectively activate muscles due to its unique design features, including its thin substrate, high conformability, high channel count, on-device ground, and the material properties of its platinum nanorod contacts. Through computational and in vivo studies, we show that SpineWrap can selectively recruit muscles in the rat lower limb and identify stimulation hotspots at a submillimeter resolution, maximizing muscle recruitment selectivity. We also investigate the effect of channel count and density on muscle recruitment selectivity and show that rat spinal cord arrays require submillimeter pitches to achieve maximal selectivity. SpineWrap represents an advancement in EES technology and, when adapted to be used chronically, has the potential to improve SCI treatment by providing more refined stimulation.

  PublisherOA PDFDOI

• A Scalable 256-Channel 12-mA 0.06%-Current-Mismatch 22-V Neurostimulator with Real-Time Current Calibration and Compliance Monitoring

  2025-04-13

  article

  Pulsed electrical stimulation (PES) is the gold standard for diagnostic [1] and therapeutic [2] applications, including functional and pathological mapping and treatment of neurological diseases with deep brain stimulation. Unfortunately, most clinical applications rely on electrode grid technologies with limited channels and poor spatial resolution. Recent advances, such as platinum nanorod electrode (PtNR) grids [3], hold the promise of PES with high channel counts, high spatial resolution, and enable heterogeneous electrode profiles (e.g., recording and stimulating contacts) in the same implant. However, new electronics are required to realize the benefits of such advanced grids. Specifically, electrical neurostimulators must simultaneously address new and challenging requirements, including a) high stimulation currents (>10mA) for electrodes of varying diameters; b) high electrode voltage compatibility (>20V) with real-time compliance monitoring; c) high channel counts (~100s) with low current mismatch <0.1%) across channels to improve stimulation focality; and d) cycle-by-cycle charge balancing to avoid electrode corrosion and tissue damage from residual charge build-up. These are the goals of this work.

  PublisherDOI

• A 2.5-20kSps in-Pixel Direct Digitization Front-End for ECoG with In-Stimulation Recording

  2024-04-21 · 9 citations

  article

  Closed-loop neuromodulation promises to enhance treatment for movement disorders, pain, and epilepsy. Advancements in low-im-pedance, high-density recording grids [1] have paved the way for low-noise neural recording systems with high spatial and temporal resolution. However, a conventional high-density neural recording signal path with programmable gain amplifiers (PGAs) and a shared ADC [2] saturates during stimulation because of the high amplifier gain. Due to a fundamental tradeoff with the input high-pass cutoff frequency (for dc electrode offset elimination), it takes hundreds of ms to recover, leading to critical data loss. Recent advances in direct digitization-based analog front-ends (AFEs) overcome this limitation by forgoing the amplifier and directly connecting the electrode to a high dynamic range ADC. Directly using a continuous time <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\Delta\Sigma$</tex> mod-ulator (CTDSM) for this application has several notable challenges: slow recovery/instability during artifacts beyond the input range, power and area limitations, and low input impedance <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$(Z_{\text{in}})$</tex> . We report a 4×2 array of per-pixel 2 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">nd</sup> -order <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\Delta\Sigma$</tex> ADCs (including the decimation filter) for ECoG with the fastest (sub-ms) artifact recovery time, ena-bling in-stimulation recording and power-efficient bandwidth scaling.

  PublisherDOI

Recent grants

• Force Sensing Surgical Forceps Using Novel Piezoelectric TFT Array for Robotic Surgery

  NSF · $360k · 2021–2023

• SNM: Scalable Nanomanufacturing of Fab Compatible High-Density Nanowire Arrays for High-Throughput Drug Screening

  NSF · $1.6M · 2017–2022

• NIH Grant DP2EB029757

  NIH · $2.4M · 2024

• Thin, High-Density, High-Performance, Depth and Surface Microelectrodes for Diagnosis and Treatment of Epilepsy

  NIH · $2.4M · 2021–2026

• 3-D Nanowire Heterostructures from Earth Abundant Materials by Low-cost Fabrication Process for High-efficiency Photoelectrochemical Hydrogen Generation

  NSF · $298k · 2012–2015

Frequent coauthors

• S. T. Picraux

  Los Alamos National Laboratory

  138 shared

• Jinkyoung Yoo

  Center for Integrated Nanotechnologies

  110 shared

• Wei Tang

  Shandong Academy of Sciences

  103 shared

• Binh‐Minh Nguyen

  98 shared

• Renjie Chen

  76 shared

• Yang Liu

  Beihua University

  65 shared

• Daniel R. Cleary

  Neurological Surgery

  61 shared

• Jianyu Huang

  Yanshan University

  54 shared

Labs

• Integrated Electronics and Biointerfaces LaboratoryPI

  Novel and Clinical Devices for Interfacing with the Brain and Spine; Gallium Nitride Materials and Devices

Education

• B.S., Physics/Electronics

  Lebanese University

  2001

• M.S., Electrical Engineering

  Southern Methodist University

  2003

• Ph.D., Electrical Engineering

  UC San Diego

  2008

Awards & honors

• Best Paper Award at every conference series and technical so…
• Distinguished Postdoctoral Performance Award
• Achievement Awards at Los Alamos National Laboratory
• NSF Early Career Award (2014)
• Jacobs School of Engineering Teacher of the Year Award in El…