Yesterday morning, I was motoring along a monotonous stretch of highway with the cruise control on when my cell phone dinged, and a random “Inquiry via Psychology Today” email from Western University’s “BrainsCAN” popped up on the screen. At first glance, this inquiry gave me a rush of excitement and piqued my curiosity. Luckily, I spotted a “Rest Area” sign a few moments later, so I pulled over to read more closely. The email said: “Hello Christopher, Given your interest in the cerebellum, I thought you might be interested in a recent paper from Western University and the University of California, Berkeley providing researchers (and anyone interested) with a functional, task-based map of the human cerebellum. You can find our tweet with the links here.”

Source: Diedrichsen Lab, Western University Canada.

As you can see by clicking on this link, the July 22 BrainsCAN at Western University tweet features a CGI-looking GIF of their new brain map in action (specifically the animated movie task) and says, “The cerebellum is the second largest structure in the human brain. Now for the first time, researchers have a functional task-based map of the cerebellum developed by Western University’s Diedrichsen lab and former Western student, Maedbh King (currently at UC Berkeley).”

After digesting the linked contents in this tweet for a minute or two, my gut instinct was to report on these breathtaking new brain maps immediately. Unfortunately, I had hundreds of miles to drive before reaching civilization. So, I sent a reply indicating I was on the road but was eager to write a post about the new state-of-the-art “Cerebellar Atlas Viewer” from Jörn Diedrichsen's lab and would be in touch with some questions for the researchers later in the day.

Last night, I sent a note with some questions for the researchers. My email said:

This morning, I heard back from Dr. Jörn Diedrichsen, Computational Neuroscience Professor at Western; below is his email response to the following questions:

How does your map differ from the map described in the paper, Functional gradients of the cerebellum (Guell et al., 2018)?

The article, "Functional gradients of the cerebellum," attempts something similar to the goal of our project. However, there are two important differences that make our paper distinct. a. The above paper is based on resting-state correlations only, while we are using a rich task-based data set. That means that we can observe the cerebellum under a much richer set of mental states and characterize each region with unprecedented detail with its functional profile. b. The above paper is based on “gradients”—that is the notion that function varies slowly and smoothly across the cerebellum. Our paper shows (for the first time) that this is not the case. There are real functional boundaries in the cerebellum that generalize across tasks. This has important implications both for understanding cerebellar function and practical implications of how to perform analysis.

What makes this "cerebellar atlas viewer" noteworthy?

We have developed a flat-map representation that allows an overview over cerebellar activity patterns. However, the connection between the flat map and the traditional volume-based display is hard to understand. The viewer now allows the linked view of both volume and surface based display to provide a full appreciation of cerebellar functional anatomy. It also collects the most relevant functional data we currently have about the human cerebellum. There were a number of surprising findings from the map including the fact that there are real functional boundaries in the cerebellum. We were also surprised to find: a. the consistency and strength of activity pattern related to cognitive task without movement—for example theory of mind and action observation. b. the fact that the traditional lobular boundaries do not at all relate to functional boundaries.

How will the atlas be used by neuroscientists in the future?

Scientist will hopefully be able to use the atlas to: a. interpret their finding in light of a full functional characterization in the cerebellum b. derive specific hypotheses about clinical groups that can be tested The data set itself can be used to develop better procedures for new methods to individually characterize cerebellar organization—something very important to determine the role of the cerebellum in mental disorders.

Many thanks to Maggie MacLellan of BrainsCAN at Western University for coordinating this Q&A and to Jörn Diedrichsen for your quick reply and insightful responses.