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The growing interdisciplinary research field of psycholinguistics is in constant need of new and up-to-date tools which will allow researchers to answer complex questions, but also expand on languages other than English, which dominates the field. One type of such tools are picture datasets which provide naming norms for everyday objects. However, existing databases tend to be small in terms of the number of items they include, and have also been normed in a limited number of languages, despite the recent boom in multilingualism research. In this paper we present the Multilingual Picture (Multipic) database, containing naming norms and familiarity scores for 500 coloured pictures, in thirty-two languages or language varieties from around the world. The data was validated with standard methods that have been used for existing picture datasets. This is the first dataset to provide naming norms, and translation equivalents, for such a variety of languages; as such, it will be of particular value to psycholinguists and other interested researchers. The dataset has been made freely available.

Modern neuroimaging techniques have provided significant improvements to our basic understanding of the cortical auditory processing. However, speech processing has so far mainly been studied with simplistic experimental designs. This thesis focuses on studying semantic speech processing in the human brain during natu- ral auditory environments, and especially on the effect of non-linguistic context produced by surrounding environmental sounds on semantic processing during sentences. Neural mechanisms of speech processing during concurrent, but unattended auditory surroundings were studied with magnetoencephalography (MEG). Speech stimuli were short Finnish sentences that were embedded with natural auditory scenes. Sentences were divided into conditions based on the expectance of the last word within a sentence (expected, improbable, semantically inappropriate) and whether the auditory scene matched the semantic content of the last word or not. Neural source modelling using minimum-norm estimates demonstrated that re- sponses from ∼350 ms onwards after the stimulus onset, were weaker when the last word was expected and matched the semantic context of the sentence. The auditory surroundings significantly affected the N400m responses: for sentences with improbable or semantically impossible endings, the N400m responses were weaker during an audio scene that semantically matched the sentence ending than during mismatching audio scene. The results suggest that the semantic context both from preceding sentential frame and from the auditory surroundings are used in parallel to generate a predictive hypothesis on the proceeding word. We hypothesize that although humans primarily utilize preceding speech to form the hypotheses on the following words, during reanalysis after incorrect prediction, the contribution of environmental auditory surrounding to the predictive hypothesis is quickly used to ease memory access and integration process., Modernit kuvantamismenetelmät ovat merkittävästi lisänneet ymmärrystämme puheenkäsittelystä aivokuorella. Toistaiseksi puheenkäsittelyä on kuitenkin tutkittu lähinnä hyvin yksinkertaisin koeasetelmin, joita ei tavata arkielämässä. Jokapäiväinen kommunikointimme tapahtuu usein erilaisissa ääniympäristöissä. Tässä lopputyössä tutkitaan puheen merkityssisällön käsittelyä luonnollisissa ääniympäristöissä ja erityisesti ei-kielellisten ympäristöäänien merkityssisällön vaikutusta lauseiden merkityksen käsittelyyn. Kyseisiä hermoston mekanismeja tutkittiin magnetoenkefalografian (MEG) avulla. ääniärsykkeet olivat lyhyitä suomenkielisiä lauseita, joiden kanssa samanaikaisesti esitettiin merkityksellisiä taustaääniä. ärsykkeet luokiteltiin lauseiden viimeisen sanan odotettavuuden (odotettu, epätodennäköinen, merkitykseltään sopimaton) ja sen mukaan, miten ympäristönäänet sopivat viimeisen sanan merkitykseen. Lähdetasolla mallinnetut tulokset osoittivat odotetusti ns. N400-efektin: n. 350 ms lauseen viimeisen sanan alusta kuulovasteet olivat heikompia, kun sana sopi muuhun lauseeseen helpomman muistiedustuksesta hakemisen ja vähemmän vaativan integrointiprosessin takia. Samanaikaisesti esitetty ympäristönääni vaikutti merkittävästi vasteisiin: vasteet epätodennäköisiin ja merkitykseltään sopimattomiin viimeisiin sanoihin olivat merkittävästi heikompia, jos ympäristönääni sopi merkitykseltään viimeiseen sanaan kuin silloin, jos ympäristönääni sopi lauserunkoon muttei viimeiseen sanaan. Johtopäätöksemme on, että vaikka kuulija pääsääntöisesti hyödyntää edeltävää lauserakennetta ennakoidessaan seuraavien sanojen merkitystä, myös samanaikaisesti kuultuun ympäristönääneen liittyvää sisältöä hyödynnetään ennakoitaessa tulevaa sanaa helpomman muistihaun ja integraation tukemiseksi.

This combined fMRI and MEG study investigated brain activations during listening and attending to natural auditory scenes. We first recorded, using in ear microphones, vocal non-speech sounds, and environmental sounds that were mixed to construct auditory scenes containing two concurrent sound streams. During the brain measurements, subjects attended to one of the streams while spatial acoustic information of the scene was either preserved (stereophonic sounds) or removed (monophonic sounds). Compared to monophonic sounds, stereophonic sounds evoked larger blood-oxygenation-level-dependent (BOLD) fMRI responses in the bilateral posterior superior temporal areas, independent of which stimulus attribute the subject was attending to. This finding is consistent with the functional role of these regions in the (automatic) processing of auditory spatial cues. Additionally, significant differences in the cortical activation patterns depending on the target of attention were observed. Bilateral planum temporale and inferior frontal gyrus were preferentially activated when attending to stereophonic environmental sounds, whereas when subjects attended to stereophonic voice sounds, the BOLD responses were larger at the bilateral middle superior temporal gyrus and sulcus, previously reported to show voice sensitivity. In contrast, the time-resolved MEG responses were stronger for mono- than stereophonic sounds in the bilateral auditory cortices at similar to 360 ms after the stimulus onset when attending to the voice excerpts within the combined sounds. The observed effects suggest that during the segregation of auditory objects from the auditory background, spatial sound cues together with other relevant temporal and spectral cues are processed in an attention-dependent manner at the cortical locations generally involved in sound recognition. More synchronous neuronal activation during monophonic than stereophonic sound processing, as well as (local) neuronal inhibitory mechan

Temporal and frontal activations have been implicated in learning of novel word forms, but their specific roles remain poorly understood. The present magnetoencephalography (MEG) study examines the roles of these areas in processing newly-established word form representations. The cortical effects related to acquiring new phonological word forms during incidental learning were localized. Participants listened to and repeated back new word form stimuli that adhered to native phonology (Finnish pseudowords) or were foreign (Korean words), with a subset of the stimuli recurring four times. Subsequently, a modified 1-back task and a recognition task addressed whether the activations modulated by learning were related to planning for overt articulation, while parametrically added noise probed reliance on developing memory representations during effortful perception. Learning resulted in decreased left superior temporal and increased bilateral frontal premotor activation for familiar compared to new items. The left temporal learning effect persisted in all tasks and was strongest when stimuli were embedded in intermediate noise. In the noisy conditions, native phonotactics evoked overall enhanced left temporal activation. In contrast, the frontal learning effects were present only in conditions requiring overt repetition and were more pronounced for the foreign language. The results indicate a functional dissociation between temporal and frontal activations in learning new phonological word forms: the left superior temporal responses reflect activation of newlyestablished word-form representations, also during degraded sensory input, whereas the frontal premotor effects are related to planning for articulation and are not preserved in noise.

Functional magnetic resonance imaging (fMRI) can provide millimeter-scale spatial resolution for brain imaging, but the extent of the activation is difficult to determine as the displayed data are the result of statistical inference based on noisy signals. Here the limits of spatial resolution in fMRI are reviewed, including both physiological and methodological factors that restrict the analysis of the extent of activation. Then simulations indicating the importance of the signal-to-noise ratio (SNR) and the spatial shape of the BOLD signal for estimation of the extent of the observed fMRI activation are presented. The effect of the SNR is smaller for sharply delineated than diffuse activations, and a similar apparent activity pattern can be obtained with different combinations of signal shapes and noise levels. One way to obtain better estimates of the extent of the activated area is to increase the SNR by, e.g. signal averaging., Toiminnallisella magneettikuvauksella voidaan tutkia aivojen toimintaa parhaimmillaan millimetrien tarkkuudella. Aktivoituneiden aivoalueiden laajuuksien arvioiminen on kuitenkin hankalaa: Mitatut signaalit ovat kohinaisia ja tulokset perustuvat tilastolliselle päätöksenteolle. Tässä työssä on arvioitu sekä metodologisia että fysiologisia tekijöitä, jotka vaikuttavat toiminnallisen magneettikuvauksen erottelukykyyn ja aktivoituneiden aivoalueiden laajuuksien arvioimiseen. Lisäksi työssä esitetään simulaatioita, jotka osoittavat signaali-kohinasuhteen ja signaalin muodon merkityksentehdyille laajuusarvioille. Signaali-kohinasuhteen merkitys on pienempi tarkkareunaisille kuin laakeille signaaleille, ja samanlainen näennäinen alueen laajuus voi syntyä hyvin erilaisten signaalien ja kohinatasojen yhdistelmänä. Aktivoituneiden alueiden laajuusarvioita voidaan parantaa kasvattamalla signaali-kohinasuhdetta esimerkiksi keskiarvoistamalla.