Search results for "Ceph"
showing 10 items of 2036 documents
Somatosensory evoked fields after exercise induced pain
2017
The amount of research utilizing magnetoencephalography (MEG) has increased within the last few decades because of the development and better availability of equipment. With MEG, different areas of brain functionality can be studied in a variety of tasks and pathologies. Somatosensory evoked fields (SEF) are magnetic fields generated by tens of thousands of neurons firing in the primary somatosensory cortex. The purpose of this master’s thesis is to study the modulation of SEFs after exercise induced pain. The study was carried out in Jyväskylä Centre for Interdisciplinary Brain Research (CIBR). The study subjects (N=18, male 10, female 8) were healthy and suitable for MEG measurements. Dat…
Dynamics of brain activation during learning of syllable-symbol paired associations.
2019
| 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…
Automatic Processing of Changes in Facial Emotions in Dysphoria: A Magnetoencephalography Study
2018
It is not known to what extent the automatic encoding and change detection of peripherally presented facial emotion is altered in dysphoria. The negative bias in automatic face processing in particular has rarely been studied. We used magnetoencephalography (MEG) to record automatic brain responses to happy and sad faces in dysphoric (Beck’s Depression Inventory ≥ 13) and control participants. Stimuli were presented in a passive oddball condition, which allowed potential negative bias in dysphoria at different stages of face processing (M100, M170, and M300) and alterations of change detection (visual mismatch negativity, vMMN) to be investigated. The magnetic counterpart of the vMMN was el…
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…
Reproducibility of evoked and induced MEG responses to proprioceptive stimulation of the ankle joint
2022
Cortical processing of proprioceptive afference can be investigated by examining phase locked evoked and induced responses in cortical signals to passive movement stimuli. Reproducibility of evoked and induced responses has been studied using electroencephalography (EEG), but proprioceptive domain has received little attention. It is unclear whether evoked and induced responses to proprioceptive stimulation arising from the lower limbs are reproducible using magnetoencephalography (MEG). Nineteen healthy volunteers (18 right-foot dominant, 36.1 ± 6.6 yr, 7 females) were measured in two MEG sessions separated by 9 ± 5 days in which their right ankle was rotated intermittently using a pneumat…
Top-Down Predictions of Familiarity and Congruency in Audio-Visual Speech Perception at Neural Level.
2019
During speech perception, listeners rely on multimodal input and make use of both auditory and visual information. When presented with speech, for example syllables, the differences in brain responses to distinct stimuli are not, however, caused merely by the acoustic or visual features of the stimuli. The congruency of the auditory and visual information and the familiarity of a syllable, that is, whether it appears in the listener’s native language or not, also modulates brain responses. We investigated how the congruency and familiarity of the presented stimuli affect brain responses to audio-visual (AV) speech in 12 adult Finnish native speakers and 12 adult Chinese native speakers. The…
Top-Down Predictions of Familiarity and Congruency in Audio-Visual Speech Perception at Neural Level
2019
During speech perception, listeners rely on multimodal input and make use of both auditory and visual information. When presented with speech, for example syllables, the differences in brain responses to distinct stimuli are not, however, caused merely by the acoustic or visual features of the stimuli. The congruency of the auditory and visual information and the familiarity of a syllable, that is, whether it appears in the listener’s native language or not, also modulates brain responses. We investigated how the congruency and familiarity of the presented stimuli affect brain responses to audio-visual (AV) speech in 12 adult Finnish native speakers and 12 adult Chinese native speakers. The…
Top-Down Predictions of Familiarity and Congruency in Audio-Visual Speech Perception at Neural Level
2019
During speech perception, listeners rely on multimodal input and make use of both auditory and visual information. When presented with speech, for example syllables, the differences in brain responses to distinct stimuli are not, however, caused merely by the acoustic or visual features of the stimuli. The congruency of the auditory and visual information and the familiarity of a syllable, that is, whether it appears in the listener's native language or not, also modulates brain responses. We investigated how the congruency and familiarity of the presented stimuli affect brain responses to audio-visual (AV) speech in 12 adult Finnish native speakers and 12 adult Chinese native speakers. The…
Spatiotemporal dynamics of activation in motor and language areas suggest a compensatory role of the motor cortex in second language processing
2023
The involvement of the motor cortex in language understanding has been intensively discussed in the framework of embodied cognition. Although some studies have provided evidence for the involvement of the motor cortex in different receptive language tasks, the role that it plays in language perception and understanding is still unclear. In the present study, we explored the degree of involvement of language and motor areas in a visually presented sentence comprehension task, modulated by language proficiency (L1: native language, L2: second language) and linguistic abstractness (literal, metaphorical, and abstract). Magnetoencephalography data were recorded from 26 late Chinese learners of …
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…