Introduction
This was my first foray into data visualisation, back in the spring of 2023. The original poster did not have the all-black aesthetic I adopted later on, and honestly looks prettier in the original white (almost ethereal), but this is a refreshed version to bring my visual portfolio into alignment.
Network Arc Diagram
The highlight of the piece is the network arc diagram depicted above, which takes 50 parcels (small areas of cortex) from the 690-parcel Yale Brain Atlas developed at our lab.1 These 50 parcels are a subset from areas of the brain important for processing language. I won’t dive too deep into the methodology for this project, since the language mapping paper I created this for has been published in Neurology.2
Networks consist of nodes (here the brain parcels) and edges (here the white matter connections between them).
White Matter Tracts
I generated 3D glass brain models with different white matter tracts embedded within using Blender. Apparently some medical students at Johns Hopkins used the web-based interactive viewer I developed for these white matter tracts to study up on neuroanatomy.3
The connectivity data (delicate white matter filaments threading through grey cortex like mycelium through forest soil) came from more than a thousand human subjects, each brain contributing the flavour of its particular topology to our set of edges. There is a technique called diffusion MRIaIt models fibre bundles based on the tendency of water molecules to diffuse along them rather than across them. Sort of like generating a map of roads in a city based on blur from traffic moving around over the day — except the satellite uses magnetic field gradients to ‘see’, and the roads are deep underground, weaving in three dimensions. that lets us model these fibre bundles. You see three tracts on the right, where the topmost one (the arcuate fasciculus) is most crucial for language.bDamage to this tract can cause conduction aphasia, where patients can understand and produce speech but struggle to repeat what they hear.
Every word I type and you read plays a kind of note on those strings, striking the intended portion of the meaning embedding of your brain into resonance.
I programmed a way to roughly localise edges from the overall structural brain network to different white matter tracts for the project. The edges (curved arcs) have stroke colour according to that information, although most are grey (unlocalised). Their stroke width encodes the strength of structural connectivity between the given node pair.
Spiderweb Plots
There is some novelty on the left — the ‘spiderweb’ plots. Since pie charts are generally frowned upon everywhere outside school presentations and corporate environments (the human eye is not good at gauging relative angular magnitude), I came up with a sort of hybrid that pulls from the DNA of radar charts. It is also similar to the hand-drawn logo I use. The chart uses line density to encode relative proportions of language disruption for each region of the cortex, across the six different tasks that were administered.
Cortical stimulationcThe technique descends from Wilder Penfield and Herbert Jasper’s work at the Montreal Neurological Institute in the 1930s–50s, where they mapped the cortex of awake patients during surgery — producing the sensory and motor homunculi. tests cortical function with implanted electrodes. If stimulation disrupts performance on the ongoing task, that area is treated as functionally important for that task.
There are also two bubbles in the background encoding how many total stimulations took place (the grey calligram) and how many stimulations disrupted language (coloured circle).
Original White Version
One of my recurring creative struggles is that the very first thing I make in a particular domain ends up being my finest work. The full version of this poster (much more science, more muted aesthetics) won an award at the American Epilepsy Society’s meeting in Orlando in 2023 — a Young Investigator Award from the Grass Foundation.
Here is the original version in white
Figure i. The original white version — created for presentation at the American Epilepsy Society meeting, Orlando, 2023.. I wrote the code to visualise the brain network diagram on the upper right, since I wasn’t satisfied with existing solutions.
There is always some hard-to-define element in the first piece (the spark? the soul?) that I never quite manage to capture again to the same extent. I suspect it’s because there has to be something quite special about the initial idea to inspire me to go out there and learn all the things I need to make the thing in the first place. 3D modelling. Plotting libraries. Graphic design. Eventually end up moving on, trying a new domain, looking for a fresh spark.