Porthole and Stormcloud: Tools for Visualisation of Spatiotemporal M/EEG Statistics

Abstract

Electro-and magneto-encephalography are functional neuroimaging modalities characterised by their ability to quantify dynamic spatiotemporal activity within the brain. However, the visualisation techniques currently used to illustrate these effects are currently limited to single-or multi-channel time series plots, topographic scalp maps and orthographic cross-sections of the spatiotemporal data structure. Whilst these methods each have their own strength and weaknesses, they are only able to show a subset of the data and are suboptimal at articulating one or both of the space-time components.Here, we propose Porthole and Stormcloud, a set of data visualisation tools which can automatically generate context appropriate graphics for both print and screen with the following graphical capabilities: 1) Animated two-dimensional scalp maps with dynamic timeline annotation and optional user interaction;2) Three-dimensional construction of discrete clusters within sparse spatiotemporal volumes, rendered with 'cloud-like' appearance and augmented by crosssectional scalp maps indicating local maxima. These publicly available tools were designed specifically for visualisation of M/EEG spatiotemporal statistical maps, however, we also demonstrate alternate use cases of posterior probability maps and weight maps produced by machine learning classifiers.In principle, the methods employed here are transferrable to visualisation of any spatiotemporal image.

Statistical Learning and Inference Is Impaired in the Nonclinical Continuum of Psychosis

“…(FWE) corrected for multiple comparisons for the spatiotemporal peak/volume or source region. We used the Porthole and Stormcloud toolbox from Taylor and Garrido (2020) Dynamic causal modeling. Dynamic causal modeling (DCM) was used, which, similar to source reconstruction, also uses a spatial forward model.…”

DelIrium VULnerability in GEriatrics (DIVULGE) study: a protocol for a prospective observational study of electroencephalogram associations with incident postoperative delirium

“…This method allows for investigation of statistical effects across the entire dataset instead of using a priori time windows. Open-source MATLAB toolboxes Porthole and Stormcloud 53 will be employed to visualise the scalp-time images created with SPM. Porthole and Stormcloud is available at https://githubcom/JeremyATaylor/Porthole .…”

“…We will extract EEG data in the form of periodic and aperiodic power spectra from resting data (eyes open and eyes closed) and ERP component amplitude and latencies from an auditory oddball paradigm. 53 54 It is hypothesised, based on previous literature, 31 33 55–57 that those who go on to develop delirium will display increased EEG slowing and attenuated ERP amplitudes as compared with those who do not. How this pattern varies as a function of subtype, severity and duration is an exploratory aim.…”

Characteristic changes in EEG spectral powers of patients with opioid-use disorder as compared with those with methamphetamine- and alcohol-use disorders

“…Thirdly, EEG signals are transformed and quantified into a color-specific topographic map, which is associated with respective cortical activity (Duru et al, 2009;Taylor & Garrido, 2020). In epilepsy, topographic images provide a guide to remove epileptogenic zones during brain surgery (Pittau et al, 2014;Plummer et al, 2019).…”