Browsing by discipline "Kognitionsvetenskap"

The aim of this study is to examine the learning mechanisms and acquisition of non-native phoneme contrasts in young adults using neurophysiological and behavioral methods. According to the traditional view, acquiring novel phonemes after the sensitive periods in the early childhood is very difficult. However, later findings have shown that foreign phoneme contrasts can be learned at a later age, too. Acquiring new phonemic categories requires neuroplastic changes in the brain. Neurophysiological studies have examined the brain’s ability to differentiate between closely related phonemic categories at the early stage of spoken language processing by measuring, for example, event-related mismatch negativity responses (MMN). MMN, or its magnetic equivalent MMNm, is elicited when the brain registers a difference in a repetitive sensory stimulus. Studies have shown that even a moderate amount of auditory training with closely related foreign phonemes improves the brain’s ability to discriminate between them resulting in enhanced MMN or MMNm responses. In this experiment the neural mechanisms of foreign language phoneme acquisition and the learning-related neuroplastic changes were studied using magnetoencephalography (MEG) and neuromagnetic evoked responses (MMNm in particular). 20 Finnish subjects were measured in the experiment. Their task was to learn to differentiate between acoustically closely related Russian fricatives Ш /ʂ/ and Щ /ɕ(ː)/. The subjects’ differentiation skills were first tested in a behavioral task where Russian pseudoword minimal pairs were presented to them auditorily. The first phoneme in the word pairs was varied and the subjects had to report whether they heard a difference between the words or not. The same stimuli were then presented in a passive MEG task where the brain’s change detection responses were tested in an unattended situation as the subjects were watching a silent film. After the measurement the subjects practiced the phonemes at home for approximately one week by playing a learning game by computer. After training they were measured again. Structural magnetic resonance images of the subjects’ brain were also measured for MEG source localization purposes. Behavioral discrimination ability of the experimental phonemes was considerably worse than with familiar control phonemes. The discrimination skills seemed to improve by training, but the difference was not statistically significant. Contrary to the hypotheses, statistically significant MMNm responses were not found before or after training. No significant differences were found in other auditory MEG responses or their neural source current distributions between the measurements either. However, individual differences in learning were sizeable. For the subjects who improved their performance in the behavioral task a modest training-related boost in the auditory responses supporting the hypotheses could be observed. Although very small and statistically insignificant, the effect was opposite for control stimuli and did not exist in the non-learner group suggesting some sort of change in neural processing in the learner group. This study was not able to replicate the findings from various previous studies on phoneme acquisition in adulthood. Although it is likely that certain methodological limitations (e.g. small number of stimulus repetitions, challenging stimuli) affected the significance of the results, based on this study the generalizability of some of the previous findings can be called into question.

Tausta ja tavoitteet. Aikaisempi tutkimus on osoittanut videopelien vaikuttavan pelaajaan positiivisilla tavoilla, esimerkiksi kehittämällä pelaajan kognitiivisia kykyjä ja oppimistuloksia. Pelissä kehittymisen tutkimus edistää pelien positiivisten vaikutusten maksimointia niin kaupallisissa kuin opetus- ja hyötypeleissäkin. PIFF2¬¬-kehys on pelikokemuksen määrittelyn malli, johon pohjautuvilla kyselyillä voidaan mitata pelikokemuksen itsenäisiä osa-alueita ja täten pelikokemusta toistomittauksissa. Tämän tutkimuksen tavoitteena oli selvittää pelikokemuksen yhteyttä pelissä kehittymiseen. Pyrkimyksenä oli saada selville, mitkä pelikokemuksen tekijät ovat yhteydessä pelissä kehittymiseen sekä muodostaa hypoteeseja jatkotutkimukselle. Menetelmät. Tutkimuksen data saatiin yhdeksältä koehenkilöltä, jotka pelasivat tutkimusta varten kehitettyä peliä kotioloissaan kahdeksan viikon ajan. Peli yhdistää aiemmin muissa tutkimuksissa käytettyjen kaupallisten pelien ominaisuuksia. Pelaajilta kerättiin dataa heidän suoriutumisestaan pelissä toiminta-, strategia- sekä pulmaelementeissä. Lisäksi koehenkilöiden tuli täyttää jokaisen pelin jälkeen PIFF2¬¬-kehykseen pohjautuva pelikokemuskysely, jolla mitattiin pelaajan pelikokemuksen piirteitä, kuten jatkamisen halua, läsnäolon tunnetta ja kontrollia. Pelisuoriutumisdatan analysoinnin helpottamiseksi tehtiin pääkomponenttianalyysi, jolla datan dimensioita saatiin vähennettyä. Pääkomponenttianalyysin tuloksena muodostettiin yksi pelitaitomuuttuja. Yhdistettyä pelitaitomuuttujaa käytettiin kokeen aikana arvioimaan pelaajien kehitystä, jota verrattiin pelikokemuskyselyn eri muuttujiin sekä näistä muodostettuun yhteiseen pelikokemusmuuttujaan. Tulokset ja johtopäätökset. Pelikokemuksen ja pelissä kehittymisen vertailu osoitti, että jatkamisen halulla oli yhteys pelissä kehittymiseen. Yhdistetty pelitaitomuuttuja toimi hyvin mittaamaan pelaajan kehitystä tutkimuksessa käytetyssä pelissä. Johtopäätöksenä pelikokemuksella ja pelissä kehittymisellä on yhteys. Tutkimus osoittaa myös tarpeen pelikokemuksen ja pelissä kehittymisen yhteyden jatkotutkimukselle ja esittää jatkotutkimukselle hypoteesiksi jatkamisen halun olevan yhteydessä pelissä kehittymiseen.

Specific Language Impairment is a broad spectrum disorder of language development, not including deficits of non-verbal intelligence. It typically manifests in a slower rate of learning new words. According to previous research, the disorder is connected with anomalous lateralization of speech related neural processes. The neural basis of Specific Language Impairment has mainly been studied in adults and school aged children, even though the disorder manifests already in preschool age. Studying the neural representations of words and their changes during a learning process in preschool children can help to recognize the cognitive risk factors of Specific Language Impairment. This study aims to confirm, whether neural representations of words are anomalously lateralized in Specific Language Impairment. In addition, differences in the rate of formation of the neural representation of words between children with Specific Language Impairment and children with typically developed language skills are studied. 12 children with Specific Language Impairment and 12 children with typically developed linguistic abilities between the ages 3 to 6 participated in the study. The differences between groups in event related potentials for a known word and an unknown pseudoword and the changes they undergo during passive listening were explored. It was found that the evoked response potentials for both stimulus types were more clearly lateralized on the left side in linguistically typically developed children than in those with Specific Language Impairment, suggesting atypical organization of word representations. Group differences were also found in the event related potentials elicited by the pseudoword: in the control group the event related potential for the pseudoword differed significantly from the one for the known word in the beginning of the experiment (lexicality effect) and resembled it by the end of the experiment (lexicalization), whereas no such difference in the beginning of and change during the experiment was observed in the experimental group. Based on this study Specific Language Impairment is associated with anomalous neural functions both in the automatic activation of the neural representations of words and in the formation of new word representations during passive listening. Both of these phenomena may be related to abnormal language development, but the mechanisms should be determined in more detail in further investigations.

Social cognitive neuroscience is a novel and fast-growing field. This field studies the neural basis of social behaviour with the tools of cognitive neuroscience. Most of the research topics in social cognitive neuroscience concern social cognition. Social cognition is defined to be cognitive information processing about conspecifics such as other people. This thesis presents a new tool to localize brain regions related to social cognition in a brain imaging experiment using functional magnetic resonance imaging (fMRI). Named as Social Localizer, this tool is intended to be a pre-experiment protocol to define so-called regions-of-interest (ROIs) based on a rich set of stimuli presented to the subject during the fMRI scanning. The stimuli were videos, pictures and texts related to social cognition, including biological movement, social interaction, faces, theory-of-mind, body parts and action observation. We ran the Social Localizer with eighteen subjects in order to validate the functionality of the localizer in an fMRI experiment. We also used eye-tracking and keypad response with a one-back-task with the stimuli to make sure that subjects were attending to the stimuli. Overall, the results were promising – we succeeded in localizing many areas central to social cognition. However, the amount of data was not enough for the localizer to specify all ROIs in the individual level. Therefore we decided to combine activations from pairs of stimulus-classes to achieve more consistent results across the group of subjects. In addition, we analyzed the empirical group-level results. These group-level results revealed interesting research questions regarding social cognition that deserve further studying in order to be clarified. In conclusion the Social Localizer provides a promissing tool to define multiple regions-of-interest on social-cognitive criteria. In future studies of social cognition, this tool could be combined with other experimental manipulations to address novel questions in well-defined regions-of-interest.

The present study uses functional magnetic resonance imaging (fMRI) to study the neural basis of naturalistic audiovisual speech processing. The study focuses on how performing different speech-related tasks affects the neural activation observed in the brain. The neural basis of speech processing has been studied for long, but previous experiments have mainly employed paradigms with simple stimuli, such as single phonemes, syllables, and words, and unnatural tasks, such as discrimination and memory tasks. Moreover, current models of speech processing are mainly based on studies using auditory-only stimuli. In natural situations, however, the aim of speech processing is to understand the meaning of what is being said, speech is most often audiovisual, it is often selectively attended to, and the signal-to-noise ratio of the speech signal varies (due to, for example, background noise). The present study aims to study speech processing in a more naturalistic setting that takes into account the above-mentioned factors. Moreover, it compares a situation where speech is processed naturalistically to a situation where speech is processed sub-lexically, as is often done in studies of speech processing. The participants of the present study were 19 healthy adults. They were presented with audiovisual dialogues where two people discuss everyday matters. In the background of the videos, the voice of a third speaker was always present so that the participants had to selectively attend to the dialogues. The auditory and visual qualities of the dialogues were modulated on two different levels. The participants performed three different tasks: 1) A semantic task, during which the participants focused on the semantic content of the dialogues. 2) A phonological task, during which the participants focused on the phonological structure of the speech. 3) A visual task, during which the participants ignored the dialogues and focused on a fixation cross. Task-dependent effects in the neural activation were found in multiple regions of the brain. Selective attention to speech was found to activate regions in the temporal lobes and the left inferior frontal gyrus (LIFG), a result consistent with earlier research. The semantic task was found to activate areas associated with semantic and socio-cognitive processing more than either of the other tasks, while the phonological task activated the posterior portion of the LIFG as well as the ventral portion of the left premotor cortex. Interactions between the effects of task and audiovisual quality were also found in many brain areas. These results show that task-dependent effects in speech processing can be seen in widespread regions of the brain, and that audiovisual quality can modulate activation differentially during different tasks. These findings highlight the importance of using naturalistic stimuli and tasks in studies of speech processing.

Kielellä on suuri vaikutus siihen, miten jäsennämme maailman ympärillämme. Äidinkieli (ensimmäinen kieli, L1) on suuressa asemassa tässä prosessissa ja toimii usein ”linssinä” miten prosessoimme informaatiota. Tässä työssä tutkitaan miten äidinkieli vaikuttaa uuden (keinotekoisen) kielen oppimiseen. Aineisto työhön kerättiin 28 osallistujalta, joista 16 oli äidinkielenään suomea puhuvia ja 12 äidinkielenään englantia puhuvia. Osallistujat tekivät tietokoneella suoritettavan testin, jossa mitattiin reaktioaika-analyysilla osallistujan kykyä oppia sanoja uudesta kielestä. Testin aikana osallistujalle esitettiin sana-kuva pareja, joissa tiettyä kielellistä ominaisuutta esitettiin animaatiolla ja sitä kuvaavalla sanalla. Sanat koostuivat taivutetuista sanamuodoista, joissa kantasanaan oli liitetty pääte. Osa ominaisuuksista oli vain suomessa liitteinä käytettäviä päätteitä (illatiivi: taloon vrt into the house, ja elatiivi: talosta vrt out of the house), osa molemmissa kielissä liitteinä käytettäviä päätteitä (monikko: talot vrt. houses ja negaatio: taloton vrt. houseless) ja osa täysin uusia liitteinä käytettäviä päätteitä (oranssi ja liike yläkulmaan). Testin tarkoituksena on mitata osallistujien kykyä erottaa pääte kantasanastaan ja kuinka tätä sääntöä voidaan soveltaa uusiin kantasanoihin. Analyyseistä ei paljastunut merkittäviä ryhmäkohtaisia eroja. Molemmat osallistujaryhmät pystyivat oppimaan, sisäistämään ja soveltamaan kaikkia kielellisiä ominaisuuksia, mikä viittaa siihen, että kielellisten ominaisuuksien oppiminen saattaa olla hyvinkin nopeaa myös sellaisten ominaisuuksien osalta joita ei omasta äidinkielestä löydy.

The use of service design is growing business at the moment. There is a need for a renewal of services both in public and private sector. Also both public and private organizations are facing the need to reorganize their work based on the need of new services. This creates the environment for many organizational changes in short time period. The employees and stakeholders should be able to follow all these changes taking place in the services, organizations and way of working. This Master's Thesis will focus on three aspects; human cognition and change, organizational change and service design supporting the change. The focus in this research is on the usage of service design methods in a strategic change process of organization and how it influences the motivation of individual employee or stakeholder to adapt the new way of working or using the new services. The research object is the service design project of Aalto University Library where the library is facing a strategic change from traditional library towards more multi-functioning learning center. The research is executed by interviewing the participants of the research object project and observing the project work. The research showed that the co-design methods can be helpful when organization faces the strategic change by motivating and supporting the employees and stakeholders in the change process. The co-design methods can support the change of employees' and stakeholder's mindset and behavior. Communication, collaboration and community atmosphere are also supported by the co-design methods. Service design is also offering the tools to create and support the feeling of influencing in the change process. All these aspects can be supported by service design when both public and private organizations are facing the need to reorganize their work together with creating new services.

New words are acquired during childhood but also in adulthood, for example by learning neologisms or foreign languages. Known words differ from novel, previously unknown, words in that their phonological forms as well as meanings are stored in neural memory traces. This difference between familiar and novel words can also be seen in the event-related potentials (ERPs) for these stimuli measured by electroencephalogram (EEG). Earlier studies observed that when novel spoken words are presented repeatedly within a short (~14 – 30 min) exposure, the ERP response increases and begins to resemble the response to familiar words. This phenomenon is called rapid word learning, which purportedly reflects cortical memory trace formation for the newly acquired words. The neural memory trace formation for novel words with unfamiliar phonology, on the other hand, has been observed to be weaker. This Master’s thesis investigated the effect of articulatory rehearsal on rapid learning of novel words. Participants (n = 19) listened to familiar Finnish words and two types of novel words: wordforms with familiar phonology and non-native wordforms with unfamiliar phonology. Continuous EEG was recorded in two conditions with different tasks: participants were instructed to either attentively listen to and memorise the spoken word stimuli or repeat the words. aloud. The active training conditions were preceded and followed by passive listening of the same stimuli. Behavioural learning was tested with a word recognition test after both conditions. In this study the focus is on the results of the active training sessions. ERPs were analysed by comparing responses to each word type in the early, middle and late phases of attentive and articulatory training. An ERP response to novel wordforms (~50 ms after the point at which the word could be identified) was modulated by the type of training and word type. During the attentive training the response to novel wordforms with familiar phonology increased, as expected. Responses to novel non-native wordforms and familiar words showed no significant changes during attentive listening. Within the articulatory rehearsal condition, however, responses to novel non-native wordforms but also to familiar words enhanced significantly. A later response ~135 ms after word disambiguation point increased during training irrespective of condition or word type. Behavioural word recognition did not differ between training conditions, and familiar words were recognised with highest precision. The ERP-results of this study suggest that attentive training enhances learning of novel words with native phonology while repeated articulation seems to enhance the formation of neural memory traces for novel non-native words.

Musiikilla ja musiikin harrastamisella voidaan tutkimustiedon perusteella tukea lasten kielellistä kehitystä ja kuulotiedon hermostollista käsittelyä. Musiikkia myös hyödynnetään paljon esimerkiksi lukivaikeudesta kärsivien kouluikäisten lasten kuntoutuksessa. Lukivaikeuden fonologisen selitysmallin mukaan häiriön syynä ovat heikosti muodostuneet puheäänne-edustukset kuuloaivokuorella. Nämä äänne-edustukset syntyvät oman äidinkielen puheäänteille jo varhaisessa vauvaiässä, joten lukivaikeuden fonologisen teorian näkökulmasta tukitoimet tulisi aloittaa jo hyvissä ajoin ennen kouluikää. Tämän tutkimuksen tarkoituksena oli selvittää, vaikuttaako varhaisen vauvaiän musiikillinen ääniympäristö ja musiikilliset toiminnot kuuden kuukauden ikäisten vauvojen esikielelliseen kehitykseen tai puheäänten hermostolliseen käsittelyyn. Tutkimuksen aineisto kerättiin 34 vauvalta, joista yli puolella oli perinnöllinen alttius lukivaikeuden kehittymiselle. Vauvojen musiikillisia toimintoja ja esikielellistä kehitystä kartoitettiin vanhempien täyttämien kyselylomakkeiden avulla. Lisäksi vauvojen ollessa kuuden kuukauden ikäisiä he osallistuivat ERP-mittaukseen, jonka aikana heille soitettiin toistuvaa epäsanaa /ta-ta/, jonka jälkimmäisessä tavussa esiintyi satunnaisia äänen keston, korkeuden ja vokaalin muutoksia. Tämän jälkeen tarkasteltiin vauvojen viikoittaisen musiikille altistumisen määrän ja musiikillisten toimintojen yhteyttä heidän esikielellisen kehityksensä taitotasoon sekä puheäänten hermostollista käsittelyä heijastaviin ERP-vasteisiin. Tulosten perusteella musiikin hyöty vauvojen varhaiskehityksessä näyttää perustuvan pitkälti aktiivisen musiikillisen toiminnan ja sosiaalisen vuorovaikutuksen yhteisvaikutukseen. Erityisesti rytmin havaitse-miseen perustuvien sosiaalisessa vuorovaikutuksessa toteutettujen musiikillisten toimintojen, kuten tans-simisen ja rummuttelun määrä näyttää olevan yhteydessä vauvojen esikielellisen kehityksen tasoon. Tut-kimus antaa viitteitä siitä, millaisella kodin piirissä toteutettavalla musiikillisella toiminnalla voidaan tukea vauvojen esikielellisten taitojen kehitystä. Tulevaisuudessa musiikin sisällyttäminen osaksi lasten varhaiskasvatusta on mahdollisesti tehokkain kielellisen kehityksen tukitoimi myös lukivaikeuden kohdal-la.

Objectives: According to previous observations, the magnitude of variation in the working memory-related electroencephalographic (EEG) alpha oscillations between different subjects is remarkable. The purpose of this study was (1) to find out whether the standard deviation in the oscillatory responses between subjects and within the subject is greater in the alpha band than in the lower or higher frequencies, (2) to examine individual oscillatory responses of subjects, and (3) to localize the neural sources of working memory encoding and retrieval related alpha synchronization and desynchronization and study the effects of different source localizations to the observed oscillatory responses during an auditory working memory task. Methods: Eighteen subjects performed a modified version of Sternberg's memory search paradigm in which they were auditorily presented memory sets consisting of five words. The subjects' task was to decide whether the probe word was included in the previously presented memory set. EEG was recorded during the task and the data was analyzed using the event-related synchronization/desynchronization (ERS/ERD), clustering, and beamforming methods. Both averaged and individual alpha band event-related spectral perturbations (ERSP), standard deviations of ERSP responses between and within the subjects, power spectra of the subjects, and source localization results of the ERSP responses were examined. Results and conclusions: ERSP responses averaged across the subjects support previous studies: Alpha-band ERS was perceived during the memory encoding and alpha-band ERD during the memory retrieval. Standard deviations of the ERSP responses both in the group and individual level were greater in the alpha band than in the lower or higher frequencies. The individual ERSP responses varied remarkably which is not observed in studies that examine only averaged ERSP responses. Calculating distances between individual and averaged ERSP responses and clustering the obtained values provided important information on the individual variation of these responses. Memory encoding -related alpha ERS and memory retrieval -related alpha ERD sources were localized in the occipital and parietal brain areas when these responses were similar to those obtained via averaging across the subjects. This finding, which is new in connection with auditorily presented stimuli, corresponds to the results of previously conducted visual working memory studies and reveals important general level knowledge of connections between working memory processes and oscillatory EEG responses.