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This study investigated two questions. One is: To what degree is sentence processing beyond single words independent of the input modality (speech vs. reading)? The second question is: Which parts of the network recruited by both modalities is sensitive to syntactic complexity? These questions were investigated by having more than 200 participants read or listen to well-formed sentences or series of unconnected words. A largely left-hemisphere frontotemporoparietal network was found to be supramodal in nature, i.e., independent of input modality. In addition, the left inferior frontal gyrus (LIFG) and the left posterior middle temporal gyrus (LpMTG) were most clearly associated with left-branching complexity. The left anterior temporal lobe showed the greatest sensitivity to sentences that differed in right-branching complexity. Moreover, activity in LIFG and LpMTG increased from sentence onset to end, in parallel with an increase of the left-branching complexity. While LIFG, bilateral anterior temporal lobe, posterior MTG, and left inferior parietal lobe all contribute to the supramodal unification processes, the results suggest that these regions differ in their respective contributions to syntactic complexity related processing. The consequences of these findings for neurobiological models of language processing are discussed.

A commonly held assumption in cognitive neuroscience is that, because measures of human brain function are closer to underlying biology than distal indices of behavior/cognition, they hold more promise for uncovering genetic pathways. Supporting this view is an influential fMRI-based study of sentence reading/listening by Pinel et al. (2012), who reported that common DNA variants in specific candidate genes were associated with altered neural activation in language-related regions of healthy individuals that carried them. In particular, different single-nucleotide polymorphisms (SNPs) of FOXP2 correlated with variation in task-based activation in left inferior frontal and precentral gyri, whereas a SNP at the KIAA0319/TTRAP/THEM2 locus was associated with variable functional asymmetry of the superior temporal sulcus. Here, we directly test each claim using a closely matched neuroimaging genetics approach in independent cohorts comprising 427 participants, four times larger than the original study of 94 participants. Despite demonstrating power to detect associations with substantially smaller effect sizes than those of the original report, we do not replicate any of the reported associations. Moreover, formal Bayesian analyses reveal substantial to strong evidence in support of the null hypothesis (no effect). We highlight key aspects of the original investigation, common to functional neuroimaging genetics studies, which could have yielded elevated false-positive rates. Genetic accounts of individual differences in cognitive functional neuroimaging are likely to be as complex as behavioral/cognitive tests, involving many common genetic variants, each of tiny effect. Reliable identification of true biological signals requires large sample sizes, power calculations, and validation in independent cohorts with equivalent paradigms.SIGNIFICANCE STATEMENT A pervasive idea in neuroscience is that neuroimaging-based measures of brain function, being closer to underlying ne

Meanings of nouns are widely thought to be grounded in experience. The experience of the world is unique for everyone, but many experiences are shared with other people. This study investigated whether human brain-level semantic representations of items are shared between individuals. Brain activity of 20 healthy volunteers was measured using magnetoencephalography (MEG), while they were shown black-and-white photographs of concrete nouns. MEG data was analysed on the sensor level. The aim was to predict, for each participant, the presented stimuli based on the participant’s brain activation, using a model which was trained on the data of the other participants. The semantic relationship among the stimuli was modelled using a semantic feature set collected through a web-based survey. The correspondence between the stimulus items and the MEG patterns was learned and, subsequently, predicted using machine learning methods, specifically with a zero-shot decoding algorithm. Cross-subject decoding was successful at the item-level with accuracy significantly above chance level. Most commonalities in semantic representations between subjects were found at 150–250 ms and 350–550 ms after the stimulus onset. Some subjects had more similar brain responses than others, however, similar internal structures of brain responses between individuals did not directly imply good cross-subject decoding performance. Cross-subject decoding did not reach the accuracy of within-subject decoding, suggesting that semantic representations of concrete items are partly individual and partly shared. More research is needed to uncover the factors that may cause individual differences in semantic representations and in decoding of such representations in the cortex using machine learning methods., Yleisen näkemyksen mukaan sanojen merkitykset muodostuvat kokemuksen kautta. Kokemus ympäröivästä maailmasta on yksilöllinen, mutta monet kokemukset ovat yhteisiä. Tässä diplomityössä tutkittiin merkitysedustumien samankaltaisuutta eri koehenkilöiden aivokuorella. Koeasetelmassa koehenkilöiden aivoaktivaatiota mitattiin MEG-laitteella henkilöiden katsellessa musta-valkoisia valokuvia, jotka esittivät konkreettisia substantiiveja. MEG-data analysoitiin kanavatasolla, ja aivovasteiden samankaltaisuutta tutkittiin zero-shot -dekoodausalgoritmin avulla. Tavoitteena oli määrittää näytetty ärsykevalokuva koehenkilön aivoaktivaation perusteella käyttäen koneoppimismenetelmää, jossa ennustusmalli opittiin toisen koehenkilön aivoaktivaatiosta. Sanojen merkityksiä mallinnettiin ominaisuusmatriisilla, joka perustui verkkokyselyn tuloksiin. Koehenkilöiden ajattelemat ärsykesanat pystyttiin tulkitsemaan aivodatasta toiselta koehenkilöltä opitun mallin avulla tilastollisesti merkitsevällä tarkkuudella. Eniten yhtäläisyyksiä aivoaktivaatioissa löydettiin 150-250 ms ja 350-550 ms ärsykkeen esittämisen jälkeen. Havaittiin myös, että joidenkin koehenkilöiden semanttiset merkitysedustumat olivat samankaltaisempia kuin toisten. Kuitenkaan aivokuoren merkitysedustumien etäisyyksien samankaltaisuus eri koehenkilöiden välillä ei suoraan korreloinut hyvän ennustustarkkuuden kanssa. Ennustustarkkuus oli myös huonompi dekoodauksessa koehenkilöiden yli, kuin jos koneoppimismalli opetettiin ja testattiin saman koehenkilön datalla. Tuloksista voidaan päätellä, että osa merkitysten käsittelystä aivokuorella on yksilöllistä ja osa samankaltaista eri ihmisillä. Näitä yksilöllisiä eroja synnyttävien tekijöiden tunnistaminen vaatii jatkotutkimuksia.

A commonly held assumption in cognitive neuroscience is that, because measures of human brain function are closer to underlying biology than distal indices of behavior/cognition, they hold more promise for uncovering genetic pathways. Supporting this view is an influential fMRI-based study of sentence reading/listening by Pinel et al. (2012), who reported that common DNA variants in specific candidate genes were associated with altered neural activation in language-related regions of healthy individuals that carried them. In particular, different single-nucleotide polymorphisms (SNPs) of FOXP2 correlated with variation in task-based activation in left inferior frontal and precentral gyri, whereas a SNP at the KIAA0319/TTRAP/THEM2 locus was associated with variable functional asymmetry of the superior temporal sulcus. Here, we directly test each claim using a closely matched neuroimaging genetics approach in independent cohorts comprising 427 participants, four times larger than the original study of 94 participants. Despite demonstrating power to detect associations with substantially smaller effect sizes than those of the original report, we do not replicate any of the reported associations. Moreover, formal Bayesian analyses reveal substantial to strong evidence in support of the null hypothesis (no effect). We highlight key aspects of the original investigation, common to functional neuroimaging genetics studies, which could have yielded elevated false-positive rates. Genetic accounts of individual differences in cognitive functional neuroimaging are likely to be as complex as behavioral/ cognitive tests, involving many common genetic variants, each of tiny effect. Reliable identification of true biological signals requires large sample sizes, power calculations, and validation in independent cohorts with equivalent paradigms.

This dataset, colloquially known as the Mother Of Unification Studies (MOUS) dataset, contains multimodal neuroimaging data that has been acquired from 204 healthy human subjects. The neuroimaging protocol consisted of magnetic resonance imaging (MRI) to derive information at high spatial resolution about brain anatomy and structural connections, and functional data during task, and at rest. In addition, magnetoencephalography (MEG) was used to obtain high temporal resolution electrophysiological measurements during task, and at rest. All subjects performed a language task, during which they processed linguistic utterances that either consisted of normal or scrambled sentences. Half of the subjects were reading the stimuli, the other half listened to the stimuli. The resting state measurements consisted of 5 minutes eyes-open for the MEG and 7 minutes eyes-closed for fMRI. The neuroimaging data, as well as the information about the experimental events are shared according to the Brain Imaging Data Structure (BIDS) format. This unprecedented neuroimaging language data collection allows for the investigation of various aspects of the neurobiological correlates of language.

I skriften Säker och sökande intervjuas sex folkbildare; pedagoger och bibliotekarier. De berättar om utmaningarna som it-tekniken medför i deras vardagspraktik. Arbeta som lärare/bibliotekarie i dag, är det samma sak som att arbeta som lärare/bibliotekarie i morgon?, I skriften Säker och sökande intervjuas sex folkbildare; pedagoger och bibliotekarier. De berättar om utmaningarna som it-tekniken medför i deras vardagspraktik. Arbeta som lärare/bibliotekarie i dag, är det samma sak som att arbeta som lärare/bibliotekarie i morgon?