Pieter Barkema

Pieter Barkema

PhD Candidate in Cognitive Neuroscience

University College London

I am a Brain & AI Scientist at University College London, and a Scientific Programmer at Donders Institute. I am interested in how the Human Brain creates Hallucinations and learns Uncertainty, both huge problems in AI Safety. I want to leverage my unique perspective to help overcome these challenges. I currently lead two multi-year experimental brain scanning studies (7T fMRI and MEG) and one computational modelling study (Deep Neural Networks, Bayesian Modelling) to investigate how human neural networks create false beliefs (hallucination) and calculate uncertainty about its own internal states (introspection) - leading to multiple peer-reviewed articles and high-profile talks. I have professional experience evaluating and training LLMs at Google Assistant, and developed PCNportal, a collaborative open-source Machine Learning app for big data brain analysis.

Humans and LLMs are both interrogable black boxes. I want to use my scientific expertise to make LLMs become more accurate in their thinking, through experimental design and computational modelling of their internal representations.

Download my resumé .

Interests
  • Mechanistic Interpretability
  • Uncertainty Quantification
  • Science of Hallucinations
  • Computational Neuroscience
Education
  • PhD in Cognitive Neuroscience, 2026

    University College London

  • MSc in Neuroscience, 2021

    King's College London

  • BSc in Artificial Intelligence, 2019

    Utrecht University

Research & Projects

Explore my work in Neuroscience and Engineering

Postdictive Perception in Primary Visual Cortex

A 7T fMRI study investigating how the human brain reconstructs sensory reality after the fact.

Cross-Category Information (CCI)

A novel statistical framework to quantify informative variance in cortical noise using manifold learning.

PCNportal: Scalable Normative Modelling

A full-stack ML platform for brain-mapping using 10,000+ scans across 100+ global sites.

Experience

 
 
 
 
 
Research PhD Candidate
University College London (UCL)
Sep 2023 – Jul 2026 London
Investigated Human Brain and Perception using brain scanners (7T fMRI, MEG) and computational modelling (e.g. Deep Learning, Bayesian Learning). I investigated representations in the human brain and developed a theory for how the human brain creates illusions. Seperately, I modelled how the hippocampus in the human brain learn statistical patterns in the environment and calculates uncertainty.
 
 
 
 
 
Scientific Programmer
Donders Institute
Jan 2022 – Aug 2023 Netherlands
A collaborative open-source online Machine Learning app for big data brain analysis. Highly complex and expensive modelling available for free in one click through an automated parallelized computing cluster. Now ~1K unique visitors, 75 active users, 10 validated models and led to five published studies. [Python, pymc3, Bash, Docker, gunicorn]
 
 
 
 
 
Associate Linguist (LLM Training)
Google / Lionbridge
Oct 2019 – Aug 2020 London, UK
Trained, curated data for, and evaluated Large Language Models (LLMs) used by millions. Solved >100 bugs. Worked in a high-throughput RLHF-style environment to align model outputs with user intent.

Public Speaking & Presentations

Discussing Neuroscience and AI at global venues

Family Talk Royal Institution

Family Talk Royal Institution

One-hour ticketed Public Talk for 200+ people on how the brain creates our reality.

Layer-specific fMRI of Postdictive Perception at 7T

Layer-specific fMRI of Postdictive Perception at 7T

Presenting high-resolution 7T fMRI data on feedback loops in the human visual cortex.