Search results for "aivot"
showing 10 items of 101 documents
Activity level in left auditory cortex predicts behavioral performance in inhibition tasks in children
2022
Funding Information: We are grateful to Hanna-Maija Lapinkero, Suvi Karjalainen, Maria Vesterinen & Janne Rajaniemi for help with data collection and to Amit Jaiswal, Erkka Heinilä and Jukka Nenonen for their help with preprocessing and scripting. This work was supported by EU project ChildBrain (Horizon2020 Marie Skłodowska-Curie Action (MSCA) Innovative Training Network (ITN) – European Training Network (ETN), grant agreement no. 641652) and the Academy of Finland grant number 311877. Publisher Copyright: © 2022 Sensory processing during development is important for the emerging cognitive skills underlying goal-directed behavior. Yet, it is not known how auditory processing in children is…
Kognition produktiivisten kykyjen yhteinen neuraalinen perusta
2014
Ihminen pystyy luomaan rajattomasti uutta rajatusta aineistosta. Esimerkiksi rajatulla sanavarastolla voidaan luoda periaatteessa mielivaltaisen pitkiä ja monimutkaisia lauseita joita emme ole koskaan ennen kuulleet tai lukeneet. Sama luovuus pätee moniin muihinkin ihmisen kykyihin musiikista, matematiikkaan, taiteesta työkaluihin. Millään muulla eläinlajilla ei ole tavattu vastaavanlaisia kykyjä. Onko tämä ihmisen rajaton luovuus peräisin yhdestä ainoasta lähteestä? Tämän esityksen tarkoituksena on selventää käsitteitä ja periaatteita, joiden avulla voisimme muotoilla tutkimusohjelman, jolla voimme sitten lähestyä kysymystä mielen mahdollisesti yhteisen tuottavan kyvyn luonteesta. Modernit…
Driver Distraction Detection Using Bidirectional Long Short-Term Network Based on Multiscale Entropy of EEG
2022
Driver distraction diverting drivers' attention to unrelated tasks and decreasing the ability to control vehicles, has aroused widespread concern about driving safety. Previous studies have found that driving performance decreases after distraction and have used vehicle behavioral features to detect distraction. But how brain activity changes while distraction remains unknown. Electroencephalography (EEG), a reliable indicator of brain activities has been widely employed in many fields. However, challenges still exist in mining the distraction information of EEG in realistic driving scenarios with uncertain information. In this paper, we propose a novel framework based on Multi-scale entrop…
Decoding brain activities of literary metaphor comprehension: An event-related potential and EEG spectral analysis
2022
Novel metaphors in literary texts (hereinafter referred to as literary metaphors) seem to be more creative and open-ended in meaning than metaphors in non-literary texts (non-literary metaphors). However, some disagreement still exists on how literary metaphors differ from non-literary metaphors. Therefore, this study explored the neural mechanisms of literary metaphors extracted from modern Chinese poetry by using the methods of Event-Related Potentials (ERPs) and Event-Related Spectral Perturbations (ERSPs), as compared with non-literary conventional metaphors and literal expressions outside literary texts. Forty-eight subjects were recruited to make the semantic relatedness judgment afte…
Cortical correlates of language perception : neuromagnetic studies in adults and children
2007
Kielen havaitsemisen päämääränä on ymmärtää kuullun tai luetun viestin sisältö. Itse havaitseminen on meille näennäisen vaivatonta. Puheen tunnistaminen ja lukeminen ovat kuitenkin tulos monimutkaisesta aivokuorella tapahtuvasta laskennasta, jonka lähtökohtana on silmän ja korvan vastaanottama fysikaalinen signaali.Tiina Parviainen tarkasteli väitöstutkimuksessaan kielen käsittelyn aivomekanismeja normaalisti lukevilla ja lukivaikeuksisilla aikuisilla sekä lukemaan opettelevilla lapsilla. Hän selvitti kirjoitetun ja puhutun kielen käsittelyyn liittyvää aktivaatioketjua aivoissa ja siinä esiintyviä eroja aikuisten ja lasten välillä. Kielen aivomekanismien kartoituksessa on keskeistä aktivaat…
Audiovisual processing of Chinese characters elicits suppression and congruency effects in MEG
2019
Learning to associate written letters/characters with speech sounds is crucial for reading acquisition. Most previous studies have focused on audiovisual integration in alphabetic languages. Less is known about logographic languages such as Chinese characters, which map onto mostly syllable-based morphemes in the spoken language. Here we investigated how long-term exposure to native language affects the underlying neural mechanisms of audiovisual integration in a logographic language using magnetoencephalography (MEG). MEG sensor and source data from 12 adult native Chinese speakers and a control group of 13 adult Finnish speakers were analyzed for audiovisual suppression (bimodal responses…
Identification of proprioceptive thalamocortical tracts in children: comparison of fMRI, MEG, and manual seeding of probabilistic tractography
2022
Publisher Copyright: © The Author(s) 2022. Published by Oxford University Press. Studying white matter connections with tractography is a promising approach to understand the development of different brain processes, such as proprioception. An emerging method is to use functional brain imaging to select the cortical seed points for tractography, which is considered to improve the functional relevance and validity of the studied connections. However, it is unknown whether different functional seeding methods affect the spatial and microstructural properties of the given white matter connection. Here, we compared functional magnetic resonance imaging, magnetoencephalography, and manual seedin…
Physical activity and aerobic fitness show different associations with brain processes underlying anticipatory selective visuospatial attention in ad…
2021
ABSTRACTUnderlying brain processes of exercise-related benefits on executive functions and the specific contribution of physical activity vs. aerobic fitness are poorly understood, especially during adolescence. We explored whether and how physical activity and aerobic fitness are associated with selective attention and the oscillatory dynamics induced by an anticipatory spatial cue. Further, we studied whether the link between physical exercise level and cognitive control in adolescents is mediated by the task-related oscillatory activity. Magnetoencephalographic alpha oscillations during a modified Posner’s cueing paradigm were measured in 59 adolescents (37 females and 22 males, 12 to 17…
Exploring Oscillatory Dysconnectivity Networks in Major Depression During Resting State Using Coupled Tensor Decomposition
2022
Dysconnectivity of large-scale brain networks has been linked to major depression disorder (MDD) during resting state. Recent researches show that the temporal evolution of brain networks regulated by oscillations reveals novel mechanisms and neural characteristics of MDD. Our study applied a novel coupled tensor decomposition model to investigate the dysconnectivity networks characterized by spatio-temporal-spectral modes of covariation in MDD using resting electroencephalography. The phase lag index is used to calculate the functional connectivity within each time window at each frequency bin. Then, two adjacency tensors with the dimension of time frequency connectivity subject are constr…
Effect of CBASP therapy on the neurophysiological responses to pictures of neutral faces in depression : an event-related potential study
2017
Tämä pro gradu -tutkielma tarkastelee masentuneiden ja terveiden koehenkilöiden tunnetiedon käsittelyn eroja. Tarkoituksena on selvittää, onko masentuneiden ja terveiden koehenkilöiden välillä eroa kasvonilmeiden välittämän tunnetiedon käsittelyssä aivoissa, ja vaikuttaako kognitiivis-behavioraalinen CBASP-psykoterapia aivovasteisiin. Tutkimuksen 42 koehenkilöstä 32 oli masentuneita ja 10 terveitä. Masentuneet koehenkilöt jaettiin sattumanvaraisesti terapiaryhmään ja tavanomaisen hoidon ryhmään. Tutkimusmenetelmänä käytettiin EEG-aineiston ERP-analyysia. EEG-aineistosta tarkasteltiin kasvokuvien esittämiseen liittyvää aivoaktivaatiota. Keskiarvot kasvokuvien aiheuttamista vasteista lasketti…