Wiete Fehner

Imaging Science PhD candidate at Washington University in St. Louis.

PhD Research

NeuroPhoto Lab — PI: Dr. Joseph P. Culver
01/2022 – 08/2026
Biophotonics Research Center, Washington University in St. Louis

Visual Semantic Encoding & Decoding with HD-DOT

I develop model-based visual semantic encoding and decoding approaches using fiber-based and wearable High-Density Diffuse Optical Tomography (HD-DOT). This work develops advanced semantic brain mapping as an optical surrogate for fMRI, enabling neuroimaging in naturalistic and real-world environments. My research addresses complex signal processing, multivariate modeling, and semantic representation challenges.

Multivariate Functional Connectivity & Shared Representations

I refine task-free functional connectivity mapping in HD-DOT using multivariate analytical methods to improve spatial precision and clinical relevance. This includes evaluating shared semantic structure across individuals, enhancing mapping robustness for multi-session and multi-participant imaging.

Experimental Design, Data Acquisition & Method Development

  • Lead the design of naturalistic experimental paradigms for multi-session HD-DOT studies
  • Direct data acquisition for both fiber-based and wearable HD-DOT systems
  • Level II MRI trained (collect fMRI validation datasets)
  • Develop and maintain reproducible analysis pipelines in Python and MATLAB
  • Implement advanced signal processing, artifact correction, and multivariate statistical models

Learn more about HD-DOT and our imaging systems

Graduate Research Assistant

Ances Bioimaging Laboratory — PI: Dr. Beau Ances
09/2021 – 01/2022
Department of Neurology, Washington University in St. Louis

  • Conducted comparative analysis of white matter microstructure in Alzheimer’s disease vs. Down syndrome using diffusion tensor imaging (DTI)
  • Performed MRI data preprocessing (FSL, bash) and statistical modeling in R

Internship

Cognitive Neuroimaging Lab — PIs: Dr. Gabriele Gratton & Dr. Monica Fabiani
09/2021 – 01/2022 (virtual)
Beckman Institute, University of Illinois Urbana–Champaign

  • Training in diffuse optical imaging: fNIRS, EROS, pulse-DOT
  • Exposure to full optical imaging processing pipelines

Graduate Research Assistant

TBMC Optical Imaging Lab — PI: Dr. Teemu Rinne
10/2019 – 05/2021
University of Turku, Faculty of Medicine

  • Developed a novel fNIRS paradigm to examine cortical changes following cochlear implantation
  • Conducted data collection and full Python-based processing/analysis
  • Helped establish and organize a new optical imaging laboratory

Undergraduate Research Assistant

University of Bremen, Department of Education — PI: Dr. Blanka Hartmann
10/2017 – 03/2019

  • Supported educational research through data collection, literature review, and administrative coordination