0000000001109169

AUTHOR

Riitta Salmelin

The relationship between electrophysiological and hemodynamic measures of neural activity varies across picture naming tasks: A multimodal magnetoencephalography-functional magnetic resonance imaging study

Funding Information: This work was financially supported by the Academy of Finland (Finnish Center of Excellence in Computational Inference Research COIN and grants #292334, #294238 to SK; #255349, #315553 to RS; #257576 to JK; #286405 funding for TM), the Sigrid Jusélius Foundation (grant to RS), the Finnish Cultural Foundation (grant to ML), the Swedish Cultural Foundation in Finland (grant to ML), the Maud Kuistila Memorial Foundation (grant to ML), and Aalto Brain Center. Publisher Copyright: Copyright © 2022 Mononen, Kujala, Liljeström, Leppäaho, Kaski and Salmelin. Different neuroimaging methods can yield different views of task-dependent neural engagement. Studies examining the relat…

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Children show right-lateralized effects of spoken word-form learning

It is commonly thought that phonological learning is different in young children compared to adults, possibly due to the speech processing system not yet having reached full native-language specialization. However, the neurocognitive mechanisms of phonological learning in children are poorly understood. We employed magnetoencephalography (MEG) to track cortical correlates of incidental learning of meaningless word forms over two days as 6±8-year-olds overtly repeated them. Native (Finnish) pseudowords were compared with words of foreign sound structure (Korean) to investigate whether the cortical learning effects would be more dependent on previous proficiency in the language rather than ma…

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Task-Modulated Corticocortical Synchrony in the Cognitive-Motor Network Supporting Handwriting

Abstract Both motor and cognitive aspects of behavior depend on dynamic, accurately timed neural processes in large-scale brain networks. Here, we studied synchronous interplay between cortical regions during production of cognitive-motor sequences in humans. Specifically, variants of handwriting that differed in motor variability, linguistic content, and memorization of movement cues were contrasted to unveil functional sensitivity of corticocortical connections. Data-driven magnetoencephalography mapping (n = 10) uncovered modulation of mostly left-hemispheric corticocortical interactions, as quantified by relative changes in phase synchronization. At low frequencies (~2–13 Hz), enhanced …

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Attentional modulation of interhemispheric (a)symmetry in children with developmental language disorder

Funding Information: The MEG recordings were conducted at Aalto University with the support of Grant #315553 from the Academy of Finland. This research was also supported by a personal grant to DH from the Jenni and Antti Wihuri Foundation and to RS from the Sigrid Jusélius Foundation. Publisher Copyright: © 2022, The Author(s). The nature of auditory processing problems in children with developmental language disorder (DLD) is still poorly understood. Much research has been devoted to determining the extent to which DLD is associated with general auditory versus language-specific dysfunction. However, less emphasis has been given to the role of different task conditions in these dysfunctio…

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Cortical organization of auditory speech perception in children and its correlation with cognitive skills

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Picture naming yields highly consistent cortical activation patterns: test-retest reliability of magnetoencephalography recordings

AbstractReliable paradigms and imaging measures of individual-level brain activity are paramount when reaching from group-level research studies to clinical assessment of individual patients. Magnetoencephalography (MEG) provides a direct, non-invasive measure of cortical processing with high spatiotemporal accuracy, and is thus well suited for assessment of functional brain damage in patients with language difficulties. This MEG study aimed to identify, in a picture naming paradigm, source-localized evoked activity and modulations of cortical oscillations that show high test-retest reliability across measurement days in healthy individuals, demonstrating their applicability in clinical set…

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Spoken-Word Segmentation and Dyslexia

We used magnetoencephalography to elucidate the cortical activation associated with the segmentation of spoken words in nonreading-impaired and dyslexic adults. The subjects listened to binaurally presented sentences where the sentence-ending words were either semantically appropriate or inappropriate to the preceding sentence context. Half of the inappropriate final words shared two or three initial phonemes with the highly expected semantically appropriate words. Two temporally and functionally distinct response patterns were detected in the superior temporal lobe. The first response peaked at approximately 100 msec in the supratemporal plane and showed no sensitivity to the semantic appr…

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Picture naming yields highly consistent cortical activation patterns: Test–retest reliability of magnetoencephalography recordings

Reliable paradigms and imaging measures of individual-level brain activity are paramount when reaching from group-level research studies to clinical assessment of individual patients. Magnetoencephalography (MEG) provides a direct, non-invasive measure of cortical processing with high spatiotemporal accuracy, and is thus well suited for assessment of functional brain damage in patients with language difficulties. This MEG study aimed to identify, in a delayed picture naming paradigm, source-localized evoked activity and modulations of cortical oscillations that show high test–retest reliability across measurement days in healthy individuals, demonstrating their applicability in clinical set…

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Abnormal functioning of the left temporal lobe in language-impaired children

Specific language impairment is associated with enduring problems in language-related functions. We followed the spatiotemporal course of cortical activation in SLI using magnetoencephalography. In the experiment, children with normal and impaired language development heard spoken real words and pseudowords presented only once or two times in a row. In typically developing children, the activation in the bilateral superior temporal cortices was attenuated to the second presentation of the same word. In SLI children, this repetition effect was nearly nonexistent in the left hemisphere. Furthermore, the activation was equally strong to words and pseudowords in SLI children whereas in the typi…

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Dynamics of brain activation during learning of syllable-symbol paired associations.

| openaire: EC/H2020/641652/EU//ChildBrain Initial stages of reading acquisition require the learning of letter and speech sound combinations. While the long-term effects of audio-visual learning are rather well studied, relatively little is known about the short-term learning effects at the brain level. Here we examined the cortical dynamics of short-term learning using magnetoencephalography (MEG) and electroencephalography (EEG) in two experiments that respectively addressed active and passive learning of the association between shown symbols and heard syllables. In experiment 1, learning was based on feedback provided after each trial. The learning of the audio-visual associations was c…

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Removing ocular artifacts from magnetoencephalographic data on naturalistic reading of continuous texts

Naturalistic reading paradigms and stimuli consisting of long continuous texts are essential for characterizing the cortical basis of reading. Due to the highly dynamic nature of the reading process, electrophysiological brain imaging methods with high spatial and temporal resolution, such as magnetoencephalography (MEG), are ideal for tracking them. However, as electrophysiological recordings are sensitive to electromagnetic artifacts, data recorded during naturalistic reading is confounded by ocular artifacts. In this study, we evaluate two different pipelines for removing ocular artifacts from MEG data collected during continuous, naturalistic reading, with the focus on saccades and blin…

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Abnormal Auditory Cortical Activation in Dyslexia 100 msec after Speech Onset

Abstract Reading difficulties are associated with problems in processing and manipulating speech sounds. Dyslexic individuals seem to have, for instance, difficulties in perceiving the length and identity of consonants. Using magnetoencephalography (MEG), we characterized the spatio-temporal pattern of auditory cortical activation in dyslexia evoked by three types of natural bisyllabic pseudowords (/ata/, /atta/, and /a a/), complex nonspeech sound pairs (corresponding to /atta/ and /a a/) and simple 1-kHz tones. The most robust difference between dyslexic and non-reading-impaired adults was seen in the left supratemporal auditory cortex 100 msec after the onset of the vowel /a/. This N100m…

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Children show hemispheric differences in the basic auditory response properties

Auditory cortex in each hemisphere shows preference to sounds from the opposite hemifield in the auditory space. Besides this contralateral dominance, the auditory cortex shows functional and structural lateralization, presumably influencing the features of subsequent auditory processing. Children have been shown to differ from adults in the hemispheric balance of activation in higher-order auditory based tasks. We studied, first, whether the contralateral dominance can be detected in 7- to 8-year-old children and, second, whether the response properties of auditory cortex in children differ between hemispheres. Magnetoencephalography (MEG) responses to simple tones revealed adult-like cont…

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