Building patient-personalized brain simulations to improve interpretation of neuroimaging and neurostimulation data


Neuroscience as a field is very good at measuring things and poking things. It has an impressive armoury of experimental techniques using electricity, light, acoustics, biochemistry, and more to measure and modulate neural activity in everything from a blob of cells on a dish to a conscious human in a surgical theatre or an MRI scanner.

What neuroscience is less good at, for the most part, is theory; i.e. understanding the sources of the patterns we see in our measurements, and what is actually happening in the brain when we poke it with electrical stimulation and the like. The sub-field that deals with developing theoretical mechanistic understanding of brain processes is known as computational neuroscience. It does this by building mathematical models that allow us to simulate and study brain activity “in-silico”.

In our research we bring the tools of computational neuroscience to the domains of neuroimaging and brain stimulation. The paradigm we use for this, whole-brain modelling, blends elements from neurophysiology, cognitive neuroscience, neuroanatomy, connectomics, complex networks, dynamical systems, machine learning, and biophysics.

We combine whole-brain computational modelling of network dynamics, oscillations, plasticity, and cognitive function with experimental and data analytic work across multiple neuroimaging and neurostimulation modalities (EEG, MEG, s/d/fMRI, fNIRS, TMS, TES). This unique theoretical-experimental approach is applied to questions on both basic principles of brain organization, as well as how it is affected in neuropsychiatric and neurological disease.

Schematic of whole-brain modelling approach (Griffiths et al. 2022)

Research Areas

We use whole-brain computational modelling, together with neuroimaging and brain stimulation, to understand how large-scale brain dynamics emerge from network structure, and how they change in neurological and psychiatric disease. Click on an area for more info and related publications.

Neurostimulation

Modelling how TMS, tFUS and other brain stimulation techniques act on neural circuits, and using this to design better therapeutic protocols.

Models & Theory

Whole-brain, neural mass and neural field models, and the mathematical and computational tools for fitting them to neuroimaging data.

Network Structure & Dynamics

How the connectome shapes large-scale brain activity, from structure–function coupling to individual differences in cognition.

Oscillations & Rhythms

Mechanisms of alpha and other brain rhythms in corticothalamic circuits, and how they shift with brain state, age and stimulation.

Brain Damage

Stroke and neurological disorders: how damage to brain networks alters neural dynamics, cognition and recovery.

Mental Health

Computational psychiatry of depression, psychosis and schizophrenia, with a focus on biomarkers and treatment response.

Selected Publications

More publications here

Background: Intermittent theta burst stimulation (iTBS) targeting the left dorsolateral prefrontal cortex (DLPFC) is effective for …

Treatment-resistant depression (TRD) affects approximately 30% of patients with major depressive disorder. Stanford Neuromodulation …

Low-intensity transcranial focused ultrasound stimulation (TUS) is an emerging technology that shares features of both established …

Hemispheric specialization is a hallmark of brain organization, yet how functionally specialized circuits develop remains unclear. In …

Repetitive transcranial magnetic stimulation (rTMS) is a non-invasive technique to modulate brain activity, often used in treating …

Alpha rhythms are a robust phenomenon prominently observed in posterior resting state electroencephalogram (EEG) that has been shown to …

Recent developments in mathematical modeling of electroencephalography (EEG) enable the tracking of otherwise-inaccessible …

The human brain exhibits a modular and hierarchical structure, spanning low-order sensorimotor to high-order cognitive/affective …

Functional magnetic resonance imaging (fMRI) has long been a cornerstone in the study of brain activity, but its high operational …

Resting-state brain activity, as observed via functional magnetic resonance imaging (fMRI), displays non-random fluctuations whose …

A major question in systems and cognitive neuroscience is to what extent neurostimulation responses are driven by recurrent activity. …

Transcranial magnetic stimulation (TMS) is an emerging alternative to existing treatments for major depressive disorder (MDD). The …

Connectome-based neural mass modelling is the emerging computational neuroscience paradigm for simulating large-scale network dynamics …

Whole-Brain Modelling is a scientific field with a short history and a long past. Its various disciplinary roots and conceptual …

Rhythmic activity in the brain fluctuates with behaviour and cognitive state, through a combination of coexisting and interacting …

Rhythmic, collective activity is a fundamental feature of neural systems. As a result of this, many of the challenges and opportunities …

Talks & Teaching

A selection of slides, videos, and code from recent talks and tutorial workshops on a variety of topics.

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Full-day educational courses on whole-brain, connectome-based modelling at the Organization for Human Brain Mapping (OHBM) annual meetings, 2023–2025

JG’s New Books in Neuroscience podcast interview with Christopher Harris on brain-based robots for neuroscience education

JG’s New Books in Neuroscience podcast interview with GB in his new book

JG’s New Books in Neuroscience podcast interview with NC in his new book

JG’s New Books in Neuroscience podcast interview with RDF in his new book

JG’s New Books in Neuroscience podcast interview with RQQ in his new book

Using human connectome project (HCP) data

Tutorial session given at Rotman Research Institute, Baycrest (jointly given with Dr. Erin Dickie)

The spherical harmonic structure of the human connectome

Invited talk at the ‘Large scale trends in cortical organization’ workshop, Leipzig

Modelling brain dynamics at rest: practical tools and theoretical perspectives

Guest (inaugral) lecture given for the Krembil Computational Neuroscience (KCN) Events series

First of the two lectures given at the Banff International Research Station (BIRS) workshop on Topological Methods in Brain Network Analysis

Second of the two lectures given at the Banff International Research Station (BIRS) workshop on Topological Methods in Brain Network Analysis

Analysis of fMRI data: principles & techniques

Lecture given by JG at the Canadian Association for Neuroscience Meeting Satellite workshop: Neural signal and image processing: quantitative analysis of neural activity

Introduction to diffusion-weighted MRI

Workshop given by JG at Rotman Research Institute

JG & CH discuss the seminal paper by Oh et al.

John Griffiths & Christopher Harris discuss an interesting but troubled corner of modern philosophy of mind

Contact

  • john.griffiths@camh.ca
  • Krembil Centre for Neuroinformatics (KCNI); Centre for Addiction and Mental Health (CAMH): 250 College Street (Floor 12), Toronto ON