Measuring the cortical tracking of speech with optically-pumped magnetometers

Lange, Paul de; Boto, Elena; Holmes, Niall; Hill, Ryan M.; Bowtell, Richard; Wens, Vincent; Tiège, Xavier De; Brookes, Matthew J.; Bourguignon, Mathieu

doi:10.1016/j.neuroimage.2021.117969

Cited by 28 publications

(18 citation statements)

References 97 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Where interference can be effectively suppressed by other means, OPMs should be capable of measuring delta-band responses (e.g. 0.2–1.5 Hz cortical activity during speech tracking; de Lange et al., 2021 ).…”

Section: Signal Processing Strategies For Opmsmentioning

confidence: 99%

Interference suppression techniques for OPM-based MEG: Opportunities and challenges

et al. 2022

View full text Add to dashboard Cite

One of the primary technical challenges facing magnetoencephalography (MEG) is that the magnitude of neuromagnetic fields is several orders of magnitude lower than interfering signals. Recently, a new type of sensor has been developed – the optically pumped magnetometer (OPM). These sensors can be placed directly on the scalp and move with the head during participant movement, making them wearable. This opens up a range of exciting experimental and clinical opportunities for OPM-based MEG experiments, including paediatric studies, and the incorporation of naturalistic movements into neuroimaging paradigms. However, OPMs face some unique challenges in terms of interference suppression, especially in situations involving mobile participants, and when OPMs are integrated with electrical equipment required for naturalistic paradigms, such as motion capture systems. Here we briefly review various hardware solutions for OPM interference suppression. We then outline several signal processing strategies aimed at increasing the signal from neuromagnetic sources. These include regression-based strategies, temporal filtering and spatial filtering approaches. The focus is on the practical application of these signal processing algorithms to OPM data. In a similar vein, we include two worked-through experiments using OPM data collected from a whole-head sensor array. These tutorial-style examples illustrate how the steps for suppressing external interference can be implemented, including the associated data and code so that researchers can try the pipelines for themselves. With the popularity of OPM-based MEG rising, there will be an increasing need to deal with interference suppression. We hope this practical paper provides a resource for OPM-based MEG researchers to build upon.

show abstract

Section: Signal Processing Strategies For Opmsmentioning

confidence: 99%

Interference suppression techniques for OPM-based MEG: Opportunities and challenges

et al. 2022

View full text Add to dashboard Cite

show abstract

“…Indeed, similar levels of CTS were previously found during natural connected speech listening at the sentential rate (<1Hz) in children of similar age compared to adults (Vander Ghinst et al, 2019). The future use of on-scalp MEG based on optically pumped magnetoencephalography should clarify this issue (Hill et al, 2019; de Lange et al, 2021). Further studies are thus needed to address these issues and better understand the origin of the observed difference between children and adults.…”

Section: Discussionmentioning

confidence: 99%

Cortical tracking of lexical speech units in a multi-talker background is immature in school-aged children

Niesen

Bourguignon

Bertels

et al. 2022

Preprint

Self Cite

View full text Add to dashboard Cite

Children have more difficulty perceiving speech in noise than adults. Whether these difficulties relate to immature processing of prosodic or linguistic elements of the attended speech is still unclear. To address the impact of noise on linguistic processing per se, we assessed how acoustic noise impacts the cortical tracking of intelligible speech devoid of prosody in school-aged children and adults.Twenty adults and twenty children (7-9 years) listened to synthesized French monosyllabic words presented at 2.5 Hz, either randomly or in 4-word hierarchical structures wherein 2 words formed a phrase, and 2 phrases formed a sentence, with or without babble noise. Neuromagnetic responses to words, phrases and sentences were identified and source-localized.Children and adults displayed significant cortical tracking of words in all conditions, and of phrases and sentences only when words formed meaningful sentences. In children compared with adults, cortical tracking of linguistic units was lower for all units in conditions without noise, and similarly impacted by the addition of babble noise for phrase and sentence units. Critically, when there was noise, adults increased the cortical tracking of monosyllabic words in the inferior frontal gyri but children did not.This study demonstrates that the difficulties of school-aged children in understanding speech in a multi-talker background might be partly due to an immature identification of lexical but not supra-lexical linguistic units.HighlightsChildren track the hierarchical linguistic units of clear speech devoid of prosodyThis cortical tracking is left-hemisphere dominant as the adult brainBabble noise reduces cortical tracking of sentences in children and adultsUnlike adults, children are not able to enhance cortical tracking of words in noise

show abstract

“…At present, all commercially available whole-head MEG systems approved by US Food and Drug Administration (FDA) are using superconducting quantum interference (SQUID) technology with liquid helium. Whole-head MEG systems utilizing optically pumped magnetometer (OPM) technology are now available for research purposes (8)(9)(10)(11)(12)(13).…”

Section: Meg Marketmentioning

confidence: 99%

Gratifying Gizmos for Research and Clinical MEG

Jousmäki

2022

Front. Neurol.

View full text Add to dashboard Cite

Experimental designs are of utmost importance in neuroimaging. Experimental repertoire needs to be designed with the understanding of physiology, clinical feasibility, and constraints posed by a particular neuroimaging method. Innovations in introducing natural, ecologically-relevant stimuli, with successful collaboration across disciplines, correct timing, and a bit of luck may cultivate novel experiments, new discoveries, and open pathways to new clinical practices. Here I introduce some gizmos that I have initiated in magnetoencephalography (MEG) and applied with my collaborators in my home laboratory and in several other laboratories. These gizmos have been applied to address neuronal correlates of audiotactile interactions, tactile sense, active and passive movements, speech processing, and intermittent photic stimulation (IPS) in humans. This review also includes additional notes on the ideas behind the gizmos, their evolution, and results obtained.

show abstract

Measuring the cortical tracking of speech with optically-pumped magnetometers

Cited by 28 publications

References 97 publications

Interference suppression techniques for OPM-based MEG: Opportunities and challenges

Interference suppression techniques for OPM-based MEG: Opportunities and challenges

Cortical tracking of lexical speech units in a multi-talker background is immature in school-aged children

Gratifying Gizmos for Research and Clinical MEG

Contact Info

Product

Resources

About