Search results for "aivotutkimus"
showing 10 items of 41 documents
Removing ocular artifacts from magnetoencephalographic data on naturalistic reading of continuous texts
2022
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…
Taking Familiar Others’ Perspectives to Regulate Our Own Emotion: An Event-Related Potential Study
2019
Current research on emotion regulation has mainly focused on Gross’s cognitive strategies for regulating negative emotion; however, little attention has been paid to whether social cognitive processes can be used to regulate both positive and negative emotions. We considered perspective-taking as an aspect of social cognition, and investigated whether it would affect one’s own emotional response. The present study used a block paradigm and event-related potential (ERP) technology to explore this question. A 3 (perspective: self vs. pessimistic familiar other vs. optimistic familiar other) × 3 (valence: positive vs. neutral vs. negative) within-group design was employed. Thirty-six college s…
Psykoterapioitten yksinäisyys ja salutogeneesi
2023
Brain responses of dysphoric and control participants during a self‐esteem implicit association test
2021
Previous studies have reported lowered implicit self‐esteem at the behavioral level among depressed individuals. However, brain responses related to the lowered implicit self‐esteem have not been investigated in people with depression. Here, event‐related potentials were measured in 28 dysphoric participants (individuals with elevated amounts of depressive symptoms) and 30 control participants during performance of an implicit association task (IAT) suggested to reflect implicit self‐esteem. Despite equivalent behavioral performance, differences in brain responses were observed between the dysphoric and the control groups in late positive component (LPC) within 400–1,000 ms poststimulus lat…
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…
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…