Word Sense Discovery and Disambiguation

The work is based on the assumption that words with similar syntactic usage have similar meaning, which was proposed by Zellig S. Harris (1954,1968). We study his assumption from two aspects: Firstly, different meanings (word senses) of a word should manifest themselves in different usages (contexts), and secondly, similar usages (contexts) should lead to similar meanings (word senses). If we start with the different meanings of a word, we should be able to find distinct contexts for the meanings in text corpora. We separate the meanings by grouping and labeling contexts in an unsupervised or weakly supervised manner (Publication 1, 2 and 3). We are confronted with the question of how best to represent contexts in order to induce effective classifiers of contexts, because differences in context are the only means we have to separate word senses. If we start with words in similar contexts, we should be able to discover similarities in meaning. We can do this monolingually or multilingually. In the monolingual material, we find synonyms and other related words in an unsupervised way (Publication 4). In the multilingual material, we ?nd translations by supervised learning of transliterations (Publication 5). In both the monolingual and multilingual case, we first discover words with similar contexts, i.e., synonym or translation lists. In the monolingual case we also aim at finding structure in the lists by discovering groups of similar words, e.g., synonym sets. In this introduction to the publications of the thesis, we consider the larger background issues of how meaning arises, how it is quantized into word senses, and how it is modeled. We also consider how to define, collect and represent contexts. We discuss how to evaluate the trained context classi?ers and discovered word sense classifications, and ?nally we present the word sense discovery and disambiguation methods of the publications. This work supports Harris' hypothesis by implementing three new methods modeled on his hypothesis. The methods have practical consequences for creating thesauruses and translation dictionaries, e.g., for information retrieval and machine translation purposes. Keywords: Word senses, Context, Evaluation, Word sense disambiguation, Word sense discovery.

Halun häilyvät rajat : Magnus Enckellin maalausten maskuliinisuuksien ja feminiinisyyksien representaatioista ja itsen luomisesta

My PhD-thesis The uneasy borders of desire Magnus Enckell's representations of masculinities and femininities and the question how to create the self concentrates on the works of Finnish fin-de-siècle artist Magnus Enckell (1870-1925). My thesis deals with representations of masculinities, femininities, sexualities and different identity-positions. My research is about questions concerning representational ways of melancholy, androgyny, narcissism, themes of Golden Age and Double in Enckell s ouvre. These themes are analyzed by contextualizing them with different, but intersecting, discourses of varied scientific, artistic and occult ideas in the fin-de-siècle. The main point is analyze how the subject is constructed in both Foucauldian and Freudian sense and what one has to know about oneself. My approaches are based on ideas expressed in different discourses as queer-theory, Michel Foucault s genealogical epistemology and knowledge-power theory, psychoanalysis, art history and visual culture studies. My starting point lays is Foucault s idea expressed in his The History of Sexuality that the constitution of homosexual or as well as heterosexual subject inaugurates possibilities for transgressive activities e.g. by giving own voice to the sexualized subject. My main thesis is to suggest that Enckell s works in their multiple and ambiguous ways construct a phantasmatic position for viewer who may identify oneself to different desires, may construct or deconstruct a sexual identity for oneself or try to define the truth about oneself. Enckell s works should be considered as a contradictory processes which both seduce person to construct an identity and as well as lure person to pursue for the deconstruction of specific and permanent identity by celebrating the ambiguousness and discontinuity in one s identity. I m suggesting that the gazing subject feels pleasure in finding one s identity but the one must face the exposure of the melancholic structure which forms the basis of sexual desire. The subject may try to resolve one s melancholy by creating a phantasy about the original and unisexual being where desires, sexualities, phantasies and identities haven t been diverged. This can be fantasized in terms of art which forms a double for the melancholic subject who is in this limited and imaginary way able to forget for a while one s existential solitude.

Lumometsän syli : Anni Swanin satusymbolismi 1896-1923

Lumometsän syli, Anni Swanin satusymbolismi 1896-1923 on suomenkielisen satukirjallisuuden poetiikkaa ja 1900-luvun alun modernia naiseutta selvittävä feministiseen tutkimustraditioon liittyvä tutkimus. Sen kohteena ovat lasten- ja nuortenkirjailija Anni Swanin (1875-1958) satukokoelmat vuosilta 1901-1923 ja Uusi Suometar -lehden sadunomaiset novellit vuosilta 1896-1904. Tutkimus tuo uutta tietoa lastenkirjallisuuden osalta 1900-luvun alun modernin ihmisen problematiikasta. Se sisältää naissubjektin kehityskaaren ja sisäisen kasvun kohti naistaiteilijuutta. Yksityiskohtaisen tarkastelun kohteina ovat sadut Veli ja sisar (1917), Ihmekukka (1905), Marjaanan helmikruunu (1912), Aaltojen salaisuus (1901), Jääkukka (1905), Tyttö ja kuolema (1917), Merenkuningatar ja hänen poikansa (1905), Lumolinna (1905) ja Tarina Kultasirkasta (1901). Tutkimuksessa tarkastellaan Swanin satujen poeettista kieltä ja naiseuden tematiikkaa ranskalaisen postmodernin ajan feministisen viitekehyksen valossa. Siinä keskeisiä ovat Julia Kristevan psykoanalyyttispohjaiset näkemykset ja Hélène Cixous´n sekä Luce Irigarayn ajatukset feminiinisestä kirjoituksesta. Sadut kontekstualisoidaan ajankohdan symbolistiseen taidevirtaukseen ja Suomen taiteen kultakauteen. Satuja tulkitaan naiskirjailijan lajina ja erityisenä naisen metaforisen ilmaisun muotona. Satujen feministinen lukutapa purkaa perinteisiä lukemiskonventioita ja merkitsee satutekstin lukemista "toisin". Se avaa varhaista modernia naiseutta ja sille ominaista naisen ilmaisukielen erityisyyttä sekä mykkää ei-kielellistä, melankolian ilmaisua. Tutkimus tuo esiin uudenlaisen naiskirjailijan aistimusvoimaisen kielen. Swanin satusymbolismi on luonnon kauneuden synesteettista ja aistimusvoimaista kerrontaa, jolle on luonteenomaista aistiestetiikka, metaforisuus, metonymisyys ja metamorfoosit. Swan vahvistaa osaltaan naisen sankaruutta, omaa ilmaisukieltä ja ääntä. Tuloksena paljastuu satuperinteeseen verrattuna uudenlaisia tyttöyden, äitiyden, naistaiteilijuuden ja perheen malleja ja niiden representaatioita. Satumallit osoittautuvat aikanaan moderneiksi tyttösankareiksi, osin ambivalenteiksi uudenlaista naiseutta ja suhteessa oloa heijastaviksi ja ovat siten varhaisia feministisen sadun tunnusmerkkejä. Tutkimus selvittää, miten Swan rakentaa omaperäisen satusymboliikan. Satumetsä on luonnonkauniin suomalaismetsän symbolinen mielenmaisema ja samanaikaisesti sadun myyttis-symbolinen topos. Swanin luontokäsitys sisältää luonnonsuojelun ja varhaisen ekokriittisen näkemyksen. Tutkimus osoittaa Swanin satujen kytkeytyvän 1900-luvun alun modernismiin ja Suomen taiteen kultakauteen. Swan on suomenkielisen symbolistisen taidesadun kehittäjä ja feministisen sadun aloittaja.

Visual completion in an illusory figure

The visual systems of humans and animals represent physical reality in a modified way, depending on the specific demands that the species in question has for survival. The ability to perceive visual illusions is found in independently evolved visual systems, from honeybees to humans. In humans, the ability emerges early, at the age of four months. Thus the perception of illusion is likely to reflect visual processes of fundamental importance for object perception in natural vision. The experiments reported in this thesis employed various modifications of the Kanizsa triangle, a drawn configuration composed of three black disks with missing sectors on a white background. The sectors appear to form the tips of a triangle. The visual system completes the physically empty area between the disks, generally called inducers, with giving the perception of an illusory triangle. The illusory triangle consists of an illusory surface bounded by illusory contours; the triangle appears brighter than and to lie above the background. If the sectors are coloured, the colour fills the illusory area, a phenomenon known as neon colour spreading . We investigated spatial limitations on the perception of Kanizsa-type illusions and how other stimuli and viewing parameters affected these limitations. We also studied complex configurations thick, bent, mobile and chromatic inducers - to determine whether illusions combining several attributes can be perceived. The results suggest that the visual system is highly effective in completing a percept. The perception of an illusory figure is spatially scale invariant when perceived at threshold. The processing time and the number of fixations modify the percept, making the perception of the illusion more probable in various viewing conditions. Furthermore, the fact that the illusion can be perceived when only one inducer is physically present at any given moment indicates the potential of single inducers. Apparently, modelling illusory figure perception will require a combination of low-level, local processes and higher-level integrative processes. Our studies with stimuli combining several attributes relevant to object perception demonstrate that the perception of an illusory figure is flexible and is maintained also when it contains colour and volume and when shown in movement. All in all, the results confirm the assumed importance of the visual processes related with the perception of illusory figures in everyday viewing. This is indicated by the variety of inducer modifications that can be made without destroying the percept. Furthermore, the illusion can acquire additional attributes from such modifications. Due to individual differences in the perception of illusory figures, universal values for absolute performance are not always meaningful, but stable trends and general relations do exist.

Visual search and eye movements: Studies of perceptual span

In visual search one tries to find the currently relevant item among other, irrelevant items. In the present study, visual search performance for complex objects (characters, faces, computer icons and words) was investigated, and the contribution of different stimulus properties, such as luminance contrast between characters and background, set size, stimulus size, colour contrast, spatial frequency, and stimulus layout were investigated. Subjects were required to search for a target object among distracter objects in two-dimensional stimulus arrays. The outcome measure was threshold search time, that is, the presentation duration of the stimulus array required by the subject to find the target with a certain probability. It reflects the time used for visual processing separated from the time used for decision making and manual reactions. The duration of stimulus presentation was controlled by an adaptive staircase method. The number and duration of eye fixations, saccade amplitude, and perceptual span, i.e., the number of items that can be processed during a single fixation, were measured. It was found that search performance was correlated with the number of fixations needed to find the target. Search time and the number of fixations increased with increasing stimulus set size. On the other hand, several complex objects could be processed during a single fixation, i.e., within the perceptual span. Search time and the number of fixations depended on object type as well as luminance contrast. The size of the perceptual span was smaller for more complex objects, and decreased with decreasing luminance contrast within object type, especially for very low contrasts. In addition, the size and shape of perceptual span explained the changes in search performance for different stimulus layouts in word search. Perceptual span was scale invariant for a 16-fold range of stimulus sizes, i.e., the number of items processed during a single fixation was independent of retinal stimulus size or viewing distance. It is suggested that saccadic visual search consists of both serial (eye movements) and parallel (processing within perceptual span) components, and that the size of the perceptual span may explain the effectiveness of saccadic search in different stimulus conditions. Further, low-level visual factors, such as the anatomical structure of the retina, peripheral stimulus visibility and resolution requirements for the identification of different object types are proposed to constrain the size of the perceptual span, and thus, limit visual search performance. Similar methods were used in a clinical study to characterise the visual search performance and eye movements of neurological patients with chronic solvent-induced encephalopathy (CSE). In addition, the data about the effects of different stimulus properties on visual search in normal subjects were presented as simple practical guidelines, so that the limits of human visual perception could be taken into account in the design of user interfaces.

Dynamics of contour, object and face processing in the human visual cortex

The neural basis of visual perception can be understood only when the sequence of cortical activity underlying successful recognition is known. The early steps in this processing chain, from retina to the primary visual cortex, are highly local, and the perception of more complex shapes requires integration of the local information. In Study I of this thesis, the progression from local to global visual analysis was assessed by recording cortical magnetoencephalographic (MEG) responses to arrays of elements that either did or did not form global contours. The results demonstrated two spatially and temporally distinct stages of processing: The first, emerging 70 ms after stimulus onset around the calcarine sulcus, was sensitive to local features only, whereas the second, starting at 130 ms across the occipital and posterior parietal cortices, reflected the global configuration. To explore the links between cortical activity and visual recognition, Studies II III presented subjects with recognition tasks of varying levels of difficulty. The occipito-temporal responses from 150 ms onwards were closely linked to recognition performance, in contrast to the 100-ms mid-occipital responses. The averaged responses increased gradually as a function of recognition performance, and further analysis (Study III) showed the single response strengths to be graded as well. Study IV addressed the attention dependence of the different processing stages: Occipito-temporal responses peaking around 150 ms depended on the content of the visual field (faces vs. houses), whereas the later and more sustained activity was strongly modulated by the observers attention. Hemodynamic responses paralleled the pattern of the more sustained electrophysiological responses. Study V assessed the temporal processing capacity of the human object recognition system. Above sufficient luminance, contrast and size of the object, the processing speed was not limited by such low-level factors. Taken together, these studies demonstrate several distinct stages in the cortical activation sequence underlying the object recognition chain, reflecting the level of feature integration, difficulty of recognition, and direction of attention.

Temporal acuity in developmental dyslexia across the life span : Tactile, auditory, visual, and crossmodal estimations

Taustaa Kehityksellinen dysleksia (lukivaikeus) on erityinen lukemaan oppimisen vaikeus, johon liittyy usein myös vaikeuksia kirjoittamaan oppimisessa. Lukivaikeuden oletetaan useissa tapauksissa johtuvan vaikeudesta käsitellä kielen äännerakenteita (fonologinen prosessointi). Tämä poikkeavuus voi olla joko lukivaikeuden perimmäinen syy tai vaihtoehtoisesti ongelmat äänteiden käsittelyssä voivat heijastaa jotain vielä perustavamman tason vaikeutta. Eräs tällainen ehdotettu perustavan tasoin syy on poikkeavuus aistien toiminnoissa, erityisesti aistien aikatarkkuudessa. Aikatarkkuudella tarkoitetaan kykyä ja rajoja siinä, kuinka nopeasti esitettyä aistitiedon virtaa henkilö kykenee vastaanottamaan ja käsittelemään. Monet arjen toiminnot lukemisen rinnalla edellyttävät aistien erittäin tarkkaa ajallista erottelukykyä (esimerkiksi kuulo puheen ymmärtämisessä, tunto pintamateriaalin tunnistamisessa). Aikatarkkuusvaikeuksien esiintyvyyttä lukivaikeudessa on tutkittu aiemminkin, mutta yksimielisyyteen ei ole päästy siitä, onko kaikilla lukivaikeuksisilla näitä ongelmia tai mihin aisteihin vaikeudet mahdollisesti rajoittuvat. Myöskään ei tiedetä, havaitaanko aikatarkkuuden ongelmia kaiken ikäisillä lukivaikeuksisilla vai vaihteleeko mahdollinen ongelmien kuva iän mukana. Lisäksi on epäselvää, kuinka aikatarkkuuden ongelmat itseasiassa ovat yhteydessä kielen käsittelyn ja varsinaisen lukemisen vaikeuksiin. Tutkimussarjan aihe Tässä tutkimussarjassa aikatarkkuutta tutkittiin kolmessa yksittäisessä aistissa, joita olivat tunto, näkö ja kuulo, sekä kolmessa aistien välisessä yhdistelmässä, joita olivat audiotaktiilinen (kuulo-tunto), visuotaktiilinen (näkö-tunto) ja audiovisuaalinen (näkö-kuulo). Aikatarkkuutta arvioitiin kahdella eri menetelmällä, jotta saataisiin lisää tietoa siitä, missä tietyssä aikatarkkuuden osa-alueessa lukivaikeuksisilla mahdollisesti on vaikeuksia. Ensimmäisessä tehtävässä tutkittavan tuli arvioida, ovatko esitetyt ei-kielelliset ärsykkeet samanaikaisia vai eriaikaisia. Toisessa tehtävässä koehenkilön tuli arvioida esitettyjen ei-kielellisten ärsykkeiden esitysjärjestys. Molemmissa tehtävissä määriteltiin millisekuntitasolla (sekunnin tuhannesosa) se esitysnopeus, jolla koehenkilö kykeni arvioimaan ärsykkeiden ajalliset suhteet oikein. Englanninkielinen demonstraatio aikatarkkuustehtävistä löytyy internetistä (http://www.helsinki.fi/hum/ylpsy/neuropsy). Itse aikatarkkuustehtävien lisäksi tutkimussarjassa arvioitiin tutkimushenkilöiden päättelykykyä, kielellisiä toimintoja ja lukemista. Tutkimushenkilöt Tutkimuksiin osallistui 53 lukivaikeuksista ja 66 sujuvaa lukijaa, jotka oli jaettu kolmeen pääikäryhmään: lapset (8-12 vuotta), nuoret aikuiset (20-36 vuotta) ja ikääntyneemmät aikuiset (20-59 vuotta). Ikääntyneempien aikuisten ryhmä oli edelleen jaettu ikävuosikymmenluokkiin, mikä mahdollisti sen tutkimisen, vaikuttaako lisääntyvä aikuisikä lukivaikeuksisten aikatarkkuuteen (20-29, 30-39, 40-49 ja 50-59 -vuotiaat). Tutkimussarjan tulokset Aikatarkkuuden ongelmat lukivaikeuksisilla olivat yleistyneitä yli iän, aistien ja tehtävien Lukivaikeuksiset kaikissa pääikäryhmissä (lapset, nuoret aikuiset, ikääntyneemmän aikuiset) tarvitsivat samanikäisiä sujuvia lukijoita hitaamman esitystahdin, jotta he kykenivät arvioimaan ei-kielellisten ärsykkeiden ajallisen esitystavan oikein. Tämä aikatarkkuuden ongelma havaittiin lukivaikeuksisilla kaikissa aisteissa (tunto, kuulo, näkö) ja niiden yhdistelmissä (audiotaktiilinen, visuotaktiilinen, audiovisuaalinen). Lukivaikeuksisten aikatarkkuusongelmat ilmenivät edelleen molemmissa tehtävätyypeissä (samanaikaisuuden ja järjestyksen arvioinnissa). Aikatarkkuus ja sen ongelmat olivat yhteydessä äänteiden käsittelyyn Aikatarkkuus oli yhteydessä äänteiden käsittelykykyyn (fonologiseen prosessointiin), niin lapsilla kuin aikuisillakin, kaikissa aisteissa, niiden yhdistelmissä ja tehtävätyypeissä. Yhteys ei-kielellisen aikatarkkuuden ja kielellisten toimintojen välillä oli kuitenkin selkeämpi lukivaikeuksisilla kuin sujuvilla lukijoilla. Tämä tarkoittaa, että etenkin lukivaikeuksisilla ryhmätason huono aikatarkkuus oli yhteydessä huonoon äänteiden käsittelyyn (fonologiseen prosessointiin) ja päinvastoin. Suoraa yhteyttä lukemisen ja aikatarkkuuden välillä ei kuitenkaan havaittu. Lisääntyvä aikuisikä heikensi lukivaikeuksisten aikatarkkuutta suhteettoman paljon Tiedonkäsittelyn nopeuden on toistuvasti osoitettu hidastuvan normaalissa ikääntymisessä. Lisääntyvä aikuisikä (20-59 -vuotiailla) heikensikin sekä sujuvien että lukivaikeuksisten aikatarkkuutta. Toisin sanoen, mitä iäkkäämmästä aikuisesta oli kysymys, sitä hitaammin hänelle tuli esittää ärsykkeet, jotta hän kykeni arvioimaan niiden ajalliset suhteet oikein. Tämä ikään liittyvä tavanomainen hidastuminen oli kuitenkin yllättäen suhteettoman nopeaa lukivaikeuksisilla. Toisin sanoen, jo nuorilla lukivaikeuksisilla havaittu aikatarkkuuden vaikeus (ryhmäero verrattuna sujuviin lukijoihin) ei pysynyt saman suuruisena, vaan ryhmien ero kasvoi aikuisiän lisääntyessä. Tulosten merkitys Lukivaikeuden osoitettiin tässä tutkimussarjassa olevan yhteydessä yleistyneeseen vaikeuteen käsitellä ajassa nopeasti muuttuvaa ei-kielellistä aistitietoa (yli aistien ja niiden yhdistelmien, tehtävätyyppien, tutkittavien iän). Tämä osoittaa, että lukivaikeus ei ole ongelma, joka rajoittuu vain kielellisen materiaalin käsittelyn vaikeuksiin (äänteiden käsittely, lukeminen, kirjoittaminen). Nyt havaitut vaikeudet eivät myöskään rajoittuneet vain niihin aisteihin, jotka selkeimmin liittyvät lukemiseen (näkö) ja puhuttuun kieleen (kuulo); Ongelmia esiintyi myös muissa aisteissa (tunto). Lukivaikeuksisten lukijoiden ryhmätasolla havaittu aikatarkkuuden ongelma ei kuitenkaan heijastunut yksilötasolle; Jokainen lukivaikeuksinen ei ollut huono aikatarkkuustehtävissä. Näin ollen ei siis voida väittää, että kaikkien lukivaikeuksisten äänteiden käsittelyn tai lukemaan oppimisen vaikeudet voisivat selittyä aistien toimintojen poikkeavuudella. Aikatarkkuuden ongelmat eivät olleet yhteydessä varsinaiseen lukemiseen. Sekä lukivaikeuksisilla lapsilla että aikuisilla todettiin kuitenkin selkeä yhteys aikatarkkuuden ongelmien ja lukemaan oppimisen keskeisen ennakkoehdon, fonologisen prosessoinnin, välillä. Saattaa siis olla, että synnynnäinen aistien toimintojen poikkeavuus vaikuttaa yksilön suoriutumiseen jo ennen varsinaista lukemaan oppimista, kun ne taidot kehittyvät (fonologinen prosessointi), joille myöhempi lukemaan oppiminen perustuu. Ikäännyttäessä havaittu lukivaikeuksisten suhteettoman nopea aikatarkkuuden heikkeneminen osoittaa, että lukivaikeus ei voi olla ongelma, joka koskee vain lapsuusikää, tai vaikeus, joka johtuu vain kehityksen viivästymästä joka kurottaisiin iän myötä umpeen. Tulosten ymmärtämiseksi onkin muistettava kaksi seikkaa. Lukivaikeus on ensinnäkin yhdistetty synnynnäisiin, pieniin, poikkeavuuksiin aivojen rakenteissa ja toiminnoissa. Toisaalta tavanomaiseen ikääntymiseen liittyy se, että aivot kykenevät yhä huonommin korjaamaan ja kiertämään (kompensoimaan) pieniä vaurioita. Tämän perusteella tutkimussarjan tuloksista voidaan päätellä, että lukivaikeuksisten jo synnynnäisesti heikentyneet aivojen kompensointimahdollisuudet eivät ole yhtä tehokkaita puskuroimaan ikääntymisen tavanomaisia vaikutuksia kuin sujuvilla lukijoilla. Yllättävää kuitenkin on, että tämä korostunut heikkeneminen havaittiin jo suhteellisen nuorilla, työikäisillä, lukivaikeuksisilla, ennen 60 ikävuotta. Samanlaista ikäännyttäessä korostuvaa vaikeutta ei lukivaikeuksilla kuitenkaan havaittu päättelyssä, kielellisissä toiminnoissa tai itse lukemisessa. Vaikuttaakin siis siltä, että ne toiminnot, joita on harjaannutettu aktiivisesti, eivät heikkene kasvavan aikuisiän myötä yhtä suhteettomasti. Alkuperäiset artikkelit Laasonen M, Tomma-Halme J, Lahti-Nuuttila P, Service E, and Virsu V (2000) Rate of information segregation in developmentally dyslexic children, Brain and Language, 75(1), 66-81. Laasonen M, Service E, and Virsu V (2001) Temporal order and processing acuity of visual, auditory, and tactile perception in developmentally dyslexic young adults, Cognitive, Affective, and Behavioral Neuroscience, 1(4), 394-410. Laasonen M, Service E, and Virsu V (2002) Crossmodal temporal order and processing acuity in developmentally dyslexic young adults, Brain and Language, 80(3), 340-354. Laasonen M, Lahti-Nuuttila P, and Virsu V (2002) Developmentally impaired processing speed decreases more than normally with age, NeuroReport, 13(9), 1111-1113.

Sense of Community in Web Environment

The study of social phenomena in the World Wide Web has been rather fragmentary, andthere is no coherent, reseach-based theory about sense of community in Web environment. Sense of community means part of one's self-concept that has to do with perceiving oneself belonging to, and feeling affinity to a certain social grouping. The present study aimed to find evidence for sense of community in Web environment, and specifically find out what the most critical psychological factors of sense of community would be. Based on known characteristics of real life communities and sense of community, and few occational studies of Web-communities, it was hypothesized that the following factors would be the most critical ones and that they could be grouped as prerequisites, facilitators and consequences of sense of community: awareness and social presence (prerequisites), criteria for membership and borders, common purpose, social interaction and reciprocity, norms and conformity, common history (facilitators), trust and accountability (consequences). In addition to critical factors, the present study aimed to find out if this kind of grouping would be valid. Furthermore, the effect of Web-community members' background variables to sense of community was of interest. In order to answer the questions, an online-questionnaire was created and tested. It included propositions that reflect factors that precede, facilitate and follow the sense of community in Web environment. A factor analysis was calculated to find out the critical factors and analyses of variance were calculated to see if the grouping to prerequisites, facilitators and consequences was right and how the background variables would affect the sense of community in Web environment. The results indicated that the psychological structure of sense of community in Web environment could not be presented with critical variables grouped as prerequisites, facilitators and consequences. Most factors did facilitate the sense of community, but based on this data it could not be argued that some of the factors chronologically precedesense of community and some follow it. Instead, the factor analysis revealed that the most critical factors in sense of community in Web environment are 1) reciprocal involvement, 2) basic trust for others, 3) similarity and common purpose of members, and 4) shared history of members. The most influencing background variables were the member's own participation activity (indicated with reading and writing messages) and the phase in membership lifecycle (from visitor to leader). The more the member participated and the further in membership life cycle he was, the more he felt sense of community. There are many descreptions of sense of community, but the present study was one of the first to actually measure the phenomenon in Web environment, and that gained well documented, valid results based on large data, proving that sense of community in Web environment is possible, and clarifying its psychological structure, thus enhancing the understanding of sense of community in Web environment. Keywords: sense of community, Web-community, psychology of the Internet

Auditory - Visual Matching in Learning Disabilities : Intervention Studies from Finland and Sweden

The present thesis discusses relevant issues in education: 1) learning disabilities including the role of comorbidity in LDs, and 2) the use of research-based interventions. This thesis consists of a series of four studies (three articles), which deepens the knowledge of the field of special education. Intervention studies (N=242) aimed to examine whether training using a nonverbal auditory-visual matching computer program had a remedial effect in different learning disabilities, such as developmental dyslexia, Attention Deficit Disorder (ADD) and Specific Language Impairment (SLI). These studies were conducted in both Finland and Sweden. The intervention’s non-verbal character made an international perspective possible. The results of the intervention studies confirmed, that the auditory-visual matching computer program, called Audilex had positive intervention effects. In Study I of children with developmental dyslexia there were also improvements in reading skills, specifically in reading nonsense words and reading speed. These improvements in tasks, which are thought to rely on phonological processing, suggest that such reading difficulties in dyslexia may stem in part from more basic perceptual difficulties, including those required to manage the visual and auditory components of the decoding task. In Study II the intervention had a positive effect on children with dyslexia; older students with dyslexia and surprisingly, students with ADD also benefited from this intervention. In conclusion, the role of comorbidity was apparent. An intervention effect was evident also in students’ school behavior. Study III showed that children with SLI experience difficulties very similar to those of children with dyslexia in auditory-visual matching. Children with language-based learning disabilities, such as dyslexia and SLI benefited from the auditory-visual matching intervention. Also comorbidity was evident among these children; in addition to formal diagnoses, comorbidity was explored with an assessment inventory, which was developed for this thesis. Interestingly, an overview of the data of this thesis shows positive intervention effects in all studies despite learning disability, language, gender or age. These findings have been described by a concept inter-modal transpose. Self-evidently these issues need further studies. In learning disabilities the aim in the future will also be to identify individuals at risk rather than by deficit; this aim can be achieved by using research-based interventions, intensified support in general education and inclusive special education. Keywords: learning disabilities, developmental dyslexia, attention deficit disorder, specific language impairment, language-based learning disabilities, comorbidity, auditory-visual matching, research-based interventions, inter-modal transpose

Keltaista ja kimaltavaa : kodin ja koulun yhteistyöstä koulun ja kodin yhteyteen

Through this study I aim to portray connections between home and school through the patterns of thought and action shared in everyday life in a certain community. My observations are primarily based upon interviews, writings and artwork by people from home (N=32) and school (N=13) contexts. Through the stories told, I depict the characters and characteristic features of the home-school interaction by generations. According to the material, in the school days of the grandparents the focus was on discipline and order. For the parents, the focus had shifted towards knowledge, while for the pupils today, the focus lies on evaluation, through which the upbringing of the child is steered towards favourable outcomes. Teachers and those people at home hold partially different understandings of home-school interaction, both of its manifested forms and potentials. The forms of contact in use today are largely seen as one-sided. Yearning for openness and regularity is shared by both sides, yet understood differently. Common causes for failure are said to lie in plain human difficulties in communication and social interaction, but deeply rooted traditions regarding forms of contact also cast a shadow on the route to successful co-operation. This study started around the idea, that home-school interaction should be steered towards the ex-change of constructive ideas between both the home and school environments. Combining the dif-ferent views gives to something to build upon. To test this idea, I drafted a practice period, which was implemented in a small pre-school environment in the fall of 1997. My focus of interest in this project was on the handling of ordinary life information in the schools. So I combined individual views, patterns of knowledge and understanding of the world into the process of teaching. Works of art and writings by the informants worked as tools for information processing and as practical forms of building home-school interaction. Experiences from the pre-school environ-ment were later on echoed in constructing home-school interaction in five other schools. In both these projects, the teaching in the school was based on stories, thoughts and performances put to-gether by the parents, grandparents and children at home. During these processes, the material used in this study, consisting of artwork, writings and interviews (N=501), was collected. The data shows that information originating from the home environments was both a motivating and interesting addition to the teaching. There even was a sense of pride when assessing the seeds of knowledge from one’s own roots. In most cases and subjects, the homegrown information content was seamlessly connected to the functions of school and the curriculum. This project initiated thought processes between pupils and teachers, adults, children and parents, teachers and parents, and also between generations. It appeared that many of the subjects covered had not been raised before between the various participant groups. I have a special interest here in visual expression and its various contextual meanings. There art material portrays how content matter and characteristic features of the adult and parent contexts reflect in the works of the children. Another clearly noticeable factor in the art material is the impact of time-related traditions and functions on the means of visual expression. Comparing the visual material to the written material reveals variances of meaning and possibilities between these forms of expression. The visual material appears to be related especially to portraying objects, action and usage. Processing through that making of images was noted to bring back memories of concrete structures, details and also emotions. This process offered the child an intensive social connection with the adults. In some cases, with children and adults alike, this project brought forth an ongoing relation to visual expression. During this study I end up changing the concept to ‘home-school collaboration’. This widely used concept guides and outlines the interaction between schools and homes. In order to broaden the field of possibilities, I choose to use the concept ‘school-home interconnection’. This concept forms better grounds for forming varying impressions and practices when building interactive contexts. This concept places the responsibility of bridging the connection-gap in the schools. Through the experiences and innovations of thought gained from these projects, I form a model of pedagogy that embraces the idea of school-home interconnection and builds on the various impres-sions and expressions contained in it. In this model, school makes use of the experiences, thoughts and conceptions from the home environment. Various forms of expression are used to portray and process this information. This joint evaluation and observation evolves thought patterns both in school and at home. Keywords: percieving, visuality, visual culture, art and text, visual expression, art education, growth in interaction, home-school collaboration, school-home interconnection, school-home interaction model.

Developmental, functional brain imaging and electrophysiological evidence of visual and auditory working memory

Intact function of working memory (WM) is essential for children and adults to cope with every day life. Children with deficits in WM mechanisms have learning difficulties that are often accompanied by behavioral problems. The neural processes subserving WM, and brain structures underlying this system, continue to develop during childhood till adolescence and young adulthood. With functional magnetic resonance imaging (fMRI) it is possible to investigate the organization and development of WM. The present thesis aimed to investigate, using behavioral and neuroimaging methods, whether mnemonic processing of spatial and nonspatial visual information is segregated in the developing and mature human brain. A further aim in this research was to investigate the organization and development of audiospatial and visuospatial information processing in WM. The behavioral results showed that spatial and nonspatial visual WM processing is segregated in the adult brain. The fMRI result in children suggested that memory load related processing of spatial and nonspatial visual information engages common cortical networks, whereas selective attention to either type of stimuli recruits partially segregated areas in the frontal, parietal and occipital cortices. Deactivation mechanisms that are important in the performance of WM tasks in adults are already operational in healthy school-aged children. Electrophysiological evidence suggested segregated mnemonic processing of visual and auditory location information. The results of the development of audiospatial and visuospatial WM demonstrate that WM performance improves with age, suggesting functional maturation of underlying cognitive processes and brain areas. The development of the performance of spatial WM tasks follows a different time course in boys and girls indicating a larger degree of immaturity in the male than female WM systems. Furthermore, the differences in mastering auditory and visual WM tasks may indicate that visual WM reaches functional maturity earlier than the corresponding auditory system. Spatial WM deficits may underlie some learning difficulties and behavioral problems related to impulsivity, difficulties in concentration, and hyperactivity. Alternatively, anxiety or depressive symptoms may affect WM function and the ability to concentrate, being thus the primary cause of poor academic achievement in children.

Identiteettien maisemat Saskatchewanin Uudessa Suomessa : Uudisasutuksesta uusidentifikaatioon

The present study examines how the landscape of the rural immigrant colony of New Finland (Saskatchewan, Canada) has reflected the Finnish origins of the about 350 settlers and their descendants, their changing ideologies, values, sense of collectiveness and the meanings of the Finnish roots. The study also reveals the reasons and power structures behind the ethnic expressions. Researched time period runs from the beginning of the settlement in 1888 to the turn of the millennium. The research concentrates on buildings, cemeteries, personal names and place names which contain strong visual and symbolic messages and are all important constituents of mundane landscapes. For example, the studied personal names are important identity-political indexes telling about the value of the Finnish nationalism, community spirit, dual Finnish-Canadian identities and also the process of assimilation which, for example, had differences between genders. The study is based on empirical field research, and iconographical and textual interpretations supported by classifications and comparative analyses. Several interviews and literature were essential means of understanding the changing political contexts which influenced the Finnish settlement and its multiple landscape representations. Five historical landscape periods were identified in New Finland. During these periods the meanings and representations of Finnish identity changed along with national and international politics and local power structures. For example, during the Second World War Canada discouraged representations of Finnish culture because Finland and Canada were enemies. But Canada s multicultural policy in the 1980s led to several material and symbolic representations indicating the Finnish settlement after a period of assimilation and deinstitutionalization. The study shows how these representations were indications of the politics of a (selective) memory. Especially Finnish language, cultural traditions and the Evangelical-Lutheran values of the pioneers, which have been passed down to new generations, are highly valued part of the Finnish heritage. Also the work of the pioneers and their participation in the building of Saskatchewan is an important collective narrative. The selectiveness of a memory created the landscape of forgetting which includes deliberately forgotten parts of the history. For example, the occasional disputes between the congregations are something that has been ignored. The results show how the different landscape elements can open up a useful perspective to diaspora colonies or other communities also by providing information which otherwise would be indistinguishable. In this case, for example, two cemeteries close together were a sign of religious distributions among the early settlers.