Liang Wang

Advances in human intracranial electroencephalography research, guidelines and good practices

Abstract:

Since the second half of the twentieth century, intracranial electroencephalography (iEEG), including both electrocorticography (ECoG) and stereo-electroencephalography (sEEG), has provided an intimate view into the human brain. At the interface between fundamental research and the clinic, iEEG provides both high temporal resolution and high spatial specificity but comes with constraints, such as the individual's tailored sparsity of electrode sampling. Over the years, researchers in neuroscience developed their practices to make the most of the iEEG approach. Here we offer a critical review of iEEG research practices in a didactic framework for newcomers, as well addressing issues encountered by proficient researchers. The scope is threefold: (i) review common practices in iEEG research, (ii) suggest potential guidelines for working with iEEG data and answer frequently asked questions based on the most widespread practices, and (iii) based on current neurophysiological knowledge and methodologies, pave the way to good practice standards in iEEG research. The organization of this paper follows the steps of iEEG data processing. The first section contextualizes iEEG data collection. The second section focuses on localization of intracranial electrodes. The third section highlights the main pre-processing steps. The fourth section presents iEEG signal analysis methods. The fifth section discusses statistical approaches. The sixth section draws some unique perspectives on iEEG research. Finally, to ensure a consistent nomenclature throughout the manuscript and to align with other guidelines, e.g., Brain Imaging Data Structure (BIDS) and the OHBM Committee on Best Practices in Data Analysis and Sharing (COBIDAS), we provide a glossary to disambiguate terms related to iEEG research.

Authors:

  • Manuel R. Mercier

  • Anne-Sophie Dubarry

  • François Tadel

  • Pietro Avanzini

  • Nikolai Axmacher

  • Dillan Cellier

  • Maria Del Vecchio

  • Liberty S. Hamilton

  • Dora Hermes

  • Michael J. Kahana

  • Robert T. Knight

  • Anais Llorens

  • Pierre Megevand

  • Lucia Melloni

  • Kai J. Miller

  • Vitória Piai

  • Aina Puce

  • Nick F. Ramsey

  • Caspar M. Schwiedrzik

  • Sydney E. Smith

  • Arjen Stolk

  • Nicole C. Swann

  • Mariska J Vansteensel

  • Bradley Voytek

  • Liang Wang

  • Jean-Philippe Lachaux

  • Robert Oostenveld

Date: 2022

DOI: https://doi.org/10.1016/j.neuroimage.2022.119438

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Temporal dynamics and response modulation across the human visual system in a spatial attention task: an ECoG study

Abstract:

The selection of behaviorally relevant information from cluttered visual scenes (often referred to as “attention”) is mediated by a cortical large-scale network consisting of areas in occipital, temporal, parietal, and frontal cortex that is organized into a functional hierarchy of feedforward and feedback pathways. In the human brain, little is known about the temporal dynamics of attentional processing from studies at the mesoscopic level of electrocorticography (ECoG), that combines millisecond temporal resolution with precise anatomical localization of recording sites. We analyzed high-frequency broadband responses (HFB) responses from 626 electrodes implanted in 8 epilepsy patients who performed a spatial attention task. Electrode locations were reconstructed using a probabilistic atlas of the human visual system. HFB responses showed high spatial selectivity and tuning, constituting ECoG response fields (RFs), within and outside the topographic visual system. In accordance with monkey physiology studies, both RF widths and onset latencies increased systematically across the visual processing hierarchy. We used the spatial specificity of HFB responses to quantitatively study spatial attention effects and their temporal dynamics to probe a hierarchical top-down model suggesting that feedback signals back propagate the visual processing hierarchy. Consistent with such a model, the strengths of attentional modulation were found to be greater and modulation latencies to be shorter in posterior parietal cortex, middle temporal cortex and ventral extrastriate cortex compared with early visual cortex. However, inconsistent with such a model, attention effects were weaker and more delayed in anterior parietal and frontal cortex.




Authors:

  • Anne B. Martin

  • Xiaofang Yang

  • Yuri B. Saalmann

  • Liang Wang

  • Avgusta Shestyuk

  • Jack J. Lin

  • Josef Parvizi

  • Robert T. Knight

  • Sabine Kastner

Date: 2019

DOI: 10.1523/JNEUROSCI.1889-18.2018

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Effective Connectivity of the Fronto-parietal Network during Attentional Control

Authors:

  • Liang Wang

  • Xun Liu

  • Kevin Guise

  • Robert T. Knight

  • Jamshid Ghajar

  • Jin Fan

Date: 2010

DOI: 10.1162/jocn.2009.21210

PubMed: 19301995

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Abstract:

The ACC, the dorsolateral prefrontal cortex (DLPFC), and the parietal cortex near/along the intraparietal sulcus (IPS) are members of a network subserving attentional control. Our recent study revealed that these regions participate in both response anticipation and conflict processing. However, little is known about the relative contribution of these regions in attentional control and how the dynamic interactions among these regions are modulated by detection of predicted versus unpredicted targets and conflict processing. Here, we examined effective connectivity using dynamic causal modeling among these three regions during a flanker task with or without a target onset cue. We compared various models in which different connections among ACC, DLPFC, and IPS were modulated by bottom-up stimulus-driven surprise and top-down conflict processing using Bayesian model selection procedures. The most optimal of these models incorporated contextual modulation that allowed processing of unexpected (surprising) targets to mediate the influence of the IPS over ACC and DLPFC and conflict processing to mediate the influence of ACC and DLPFC over the IPS. This result suggests that the IPS plays an initiative role in this network in the processing of surprise targets, whereas ACC and DLPFC interact with each other to resolve conflict through attentional modulation implemented via the IPS.