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Tarkoitus: Tämän kirjallisuuskatsauksen tarkoituksena on selvittää, mikä kuvantamistutkimuksen perusteella selittää psykoosisairauksissa esiintyviä näköharhoja. Näköharhat on yhdistetty psykoosisairauksissa heikompaan toimintakykyyn, vaikeampiin harhaluuloihin sekä suurempaan kuolleisuuteen, ja ne lisäävät sairauden aiheuttamaa psyykkistä kärsimystä pelkoa herättävän ja todentuntuisen erityisluonteensa takia. Kuitenkin näköharhoja on tutkittu melko vähän psykoosisairauksien kontekstissa. Otoskoot jäävät usein pieniksi seurauksena näköharhojen korkeasta yhteisesiintyvyydestä yleisempien ja paremmin tunnettujen kuuloharhojen kanssa. Tuloksia on saatu vertailemalla sekä kuulo- että näköharhoista kärsiviä potilaita vain kuuloharhoista kärsiviin, ja näitä tuloksia esitellään tässä katsauksessa. Menetelmät: Kirjallisuuskatsauksen aineisto haettiin Pubmedin tietokannasta hakusanoilla (imaging) AND ("visual hallucinations") AND (schizophrenia) ja (imaging) AND ("visual hallucinations") AND (psychosis). Tulokset: Näköharhojen taustalla näyttäisi tulosten perusteella voivan vaikuttaa visuaalisen tiedon prosessointiin osallistuvien hermoverkostojen koordinaatiohäiriöitä. Salienssiverkosto SAL:n, keskeisimmin aivosaaren, DMN:a säätelevä vaikutus näyttää olevan heikompaa, mikä saattaa puolestaan myötävaikuttaa assosiaatiokorteksilla heräävään sisäsyntyiseen hyperaktivaatioon, mitä DMN tavallisesti hillitsee. Tämä spontaani, tavallista voimakkaampi aktivaatio saattaa tulla tulkituksi ulkosyntyiseksi ja ilmetä monimutkaisten näköharhojen muodossa. Primäärin näköaivokuoren toiminnan hiljaisuus saattaa heikentää normaalien palauteyhteyksien säätelevää vaikutusta assosiaatiokorteksille. Lisäksi SAL:n toimintahäiriö saattaa vaikuttaa ympäristön visuaalisten ärsykkeiden salienssiarviointiin, tuottaen merkitystä satunnaisille havainnoille. Poikkeavuutta nähdään myös tarkkaavuuden säätelyyn osallistuvilla alueilla, millä voi olla roolinsa tässä prosessointihäiriössä. Hyperkonnektiivisuus hippokampukseen voi viitata näköharhojen aikana aktivoituviin muistiedustuksiin, voimistunut konnektiivisuus mantelitumakkeeseen taas niiden mahdolliseen pelkoa herättävään sisältöön tai traumamuistojen osallisuuteen. Hippokampuksen rakenteessa olevat poikkeavuudet viittaavat hermoston kehityksen aikaiseen häiriöön osatekijänä näköharhojen taustalla. Lisäksi psykoosisairauksien näköharhoihin liittyy todennäköisenä myötävaikuttajana voimistunut dopaminerginen välittäjäainetoiminta, mikä puolestaan voi painottaa visuaalista prosessointia entistä enemmän kohti sisäsyntyistä aktivaatiota.

Memory is based on the brain’s ability to save information from the surroundings of the animal. Memory has three main functions: the encoding and consolidation of new memory traces and the retrieval. Oscillations are cyclic variations occurring in time. Neural oscillations are brain’s electric activity that can be viewed in cellular level or in the level of brain areas. The aim of this thesis is to review recent models about the role of neural oscillations in the encoding and consolidation of long term memories. Memory traces form when the connections of the neurons active in the encoding are strenghtened. New memory traces are stabilized to the long term memory in the consolidation processes. Consolidation contains both the strenghtening of local synaptic connections (synaptic consolidation) and the system consolidation, which solidifies the memory traces to the already existing information networks. According to the standard model of system consolidation new memory traces are saved simultaneously to the short term memory storage in the hippocampus and the long term storage in the cortex. The consolidation of the memory traces occurs when the memory traces in hippocampus are repeatedly reactivated which strengthens the analogous memory traces in the cortex. Neural oscillations are part of the memory processes both in awake state and sleep. In the awake state the main process is the encoding of new memories which for declarative memories is thought to occur mainly in hippocampus, mediated by for example gamma and theta oscillations. During the sleep the processes of the system consolidation are presumably in the main role, mediated by neural oscillations characteristic for different sleep stages (for example sharp-wave ripples and sleep spindles in slow wave sleep). Slow wave sleep is thought to be specifically important for the consolidation occurring in the sleep. On the other hand the role of lighter sleep stages may be greater than it has earlier been assumed. There is no complete understanding of the roles of different sleep stages and sleep time neural oscillations, and different partly contradictory, partly complementary models have been proposed.

There is apparent dualism in the internalist philosophy of mind, where a division is made between the mind and the world. In classic Cartesian dualism, the division between the mind and the world is made by separating the mind and the body from each other. Aim of this thesis was to parallelize the results and theories of neuroscience and psychology with externalist philosophy of mind. Externalist philosophy of mind poses a question to the more classical views whether an internalist and brain bound perspective is enough to explain the mind. According to the radical interpretations of externalism the mind builds on the factors of the environment, or even emerges from the relationship between man and the world. According to more moderate interpretations the relationship between mind and the world is only interactive. Externalism has also been used as a research framework for other sciences. For example, linguists Lakoff and Johnson proposed that language evolves from embodiment to abstraction. Example of this sort of development is the word “language” itself which originates from Old Latin word (lingua) meaning the tongue. The 4E –model of externalism as defined by Shaun Gallagher is used in this thesis as a framework of inquiry. The model partitions externalist theories in to four categories. The mind is embodied because mental states are affected not only by the brain, but by the states of the body as well. The mind is embedded because the mind needs an environment to function. The mind is enacted because it’s active and adapts to the environment. The mind is also extended because it’s not bound only to neural processes. The thesis progresses by covering the phenomena of neuroscience and psychology partitioned in classes defined by the 4E –model. Models addressed in the context of enactivism are cyclical by nature. Classical example of cyclical model in the field of psychology is perceptual cycle by Ulrich Neisser. A similar theme is present in Friston’s and Kiebel’s model of predictive coding. Motif’s related to embodiment have been long present in the form of for example James-Lange theory and nowadays in “The Somatic Marker Hypothesis” by Antonio Damasio. Theory of Embodied Cognition is likewise discussed in the part dealing with embodiment. Extended mind refers to the significance which objects outside of the skull can possess in relation to cognition. Another human can also be relevant to cognition, of which a traditional example is Vygotsky's Zone of Proximal Development. Mirror neurons, empathy and social neuroscience will all be covered in the extended mind chapter. Themes present in the embeddedness partition are cultural. Theory of mind, perception of time and existential questions are intertwined with our cultural environment. Applications of externalist paradigm go from mobile mental health services, experience of art, evolutionary psychology and semantic memory to transcultural perspectives, artificial intelligence and existential questions. Wrapped up in to one definition the aim of externalist research of the mind is to probe the interface between man and the world.

Tavoitteet. Arviolta 25 000 henkilöä sairastaa Suomessa vuosittain aivoverenkiertohäiriön, ja heistä noin kolmasosalla ilmenee afasiaa sen seurauksena. Afasian tyypillisin oire on nimeämiseen vaikeus. Valtaosa maailman ihmisistä käyttää arjessaan useampaa kuin yhtä kieltä, mutta tutkimuskirjallisuus on keskittynyt lähinnä yksikielisyyteen, joten tutkimustietoa monikielisyydestä tarvitaan lisää. Kuvasta nimeäminen on yksi eniten käytettyjä sanahaun arviointimenetelmiä. Tässä kandidaatintutkielmassa tarkastellaan monikielisen henkilön, jolla on afasia, kuvasta nimeämistä, ja verrataan sitä yksikielisen henkilön, jolla on afasia, kuvasta nimeämiseen Menetelmät. Kandidaatintutkielman menetelmänä käytettiin integroivaa kirjallisuuskatsausta. Aineistohaku suoritettiin joulukuussa 2016 EBSCO ja SCOPUS Elsevier tietokannoista. Hakulause muodostettiin yhdistämällä afasia ja nimeäminen monikielisyyteen. Poissulkukriteereinä olivat etenevä afasia, aivovamma, yli 65 vuoden ikä, dementia sekä kolme- tai nelikie-lisyys. Lopulliseen aineistoon valittiin tutkimukset, jotka vastasivat tutkimuskysymyksiin ja joista oli kokoteksti saatavilla Helsingin yliopiston tunnuksilla. Lopullinen aineisto koostui seitsemästä artikkelista, jotka analysoitiin sisällönanalyysin keinoin. Tulokset ja johtopäätökset. Monikielisen henkilön, jolla on afasia, kuvasta nimeämisessä ilmenee samoja virheitä kuin yksikielisellä henkilöllä. Ainoa merkittävä näissä tutkimuksissa löytynyt ero on koodinvaihto, josta on vaikeaa tietää, onko kyseessä kiertokeino vai interferenssi. Vaikuttaa siltä, että sanan samankaltaisuus kielissä aiheuttaa interferenssiä.

Tavoitteet. Anomiaa eli sananlöytämisen vaikeutta ilmenee lähestulkoon kaikilla afaattisilla henkilöillä ja se on afasian pysyvin oire. Nimeämisen kuntoutuksen taustalla tiedetään olevan monimutkainen molemmat aivopuoliskot käsittävä hermoverkosto. Kuntoutuksen hermostolliset mekanismit ovat kuitenkin monelta osin vielä epäselviä ja saadut tulokset osin ristiriitaisia. Tämän integroidun kirjallisuuskatsauksen tavoitteena on kartoittaa, miten nimeämisen kuntoutus näkyy aivotasolla kroonisessa afasiassa ja millaiset hermostolliset tekijät ovat yhteydessä kuntoutuksen vaikuttavuuteen. Menetelmä. Kandidaatintutkielman menetelmänä oli integroiva kirjallisuuskatsaus. Artikkelit haettiin Ovid Medline -tietokannasta. Hakusanoina käytettiin englanninkielisiä termejä aphasi* (afasia), treatment (hoito), therap* (terapia), rehabilitation (kuntoutus), anomia, naming (nimeäminen), "word-finding" (sanan löytäminen), neural (hermostollinen), neuroimaging (aivokuvantaminen), plasticity (muovautuvuus), reorganization (uudelleen järjestäytyminen). Rajausten jälkeen tutkimusaineistoon valikoitui seitsemän tutkimusartikkelia. Tulokset ja johtopäätökset. Tämän kirjallisuuskatsauksen perusteella kroonisessa afasiassa voidaan saavuttaa merkittäviä tuloksia nimeämisen kuntoutuksella. Tulosten perusteella kummankin aivopuoliskon alueilla on keskeinen rooli nimeämisen kuntoutuksessa. Kuntoutuksen seurauksena on havaittavissa paljon yksilöiden välistä vaihtelua aivojen hermostollisissa muutoksissa. Kuntoutuksen seurauksena voidaan havaita vasemman ja oikean aivopuoliskon aktivaation kasvua, joka viittaa aivojen toiminnalliseen uudelleen aktivaatioon ja uudelleen järjestäytymiseen. Toisaalta osalla kuntoutujista on havaittavissa vasemman ja/tai oikean aivopuoliskon aktivaation laskua, joka näyttäisi viittaavan tehostuneeseen tiedonkäsittelyyn. Saatujen tulosten perusteella vasemman ja oikean puolen alin otsalohkopoimu (inferior frontal gyrus, IFG) on keskeinen aivoalue nimeämisen kuntoutuksessa. Kuntoutuksen aikana voidaan havaita aktivaatiomuutoksia kummankin aivopuoliskon IFG-alueella. Lisäksi ennen kuntoutusta havaittu vasemman puolen IFG-alueen aktivaatiotaso ja alueen mahdollinen vaurio näyttävät olevan keskeisiä tekijöitä kuntoutusennusteen kannalta.

Goals: Minor cognitive impairment (MCI) is believed to be an intermediate state between regular aging and dementia, especially Alzheimer's disease. MCI have been used to detect older adults who have a high risk of developing dementia. However, it has not proved to be efficient in separating those who will progress to dementia from those who will not. Neuropsychiatric symptoms have been suggested as another mean to achieve better sensitivity. Neuropsychiatric symptoms are more prevalent in older adults with MCI than in those with regular cognitive functioning. Certain neuropsychiatric symptoms together with MCI increase the risk of dementia more than MCI without the neuropsychiatric symptom. Most of the research literature around neuropsychiatric symptoms and the risk of dementia has focused on depression and anxiety symptoms. However, among neuropsychiatric symptoms psychotic symptoms separate older adults with MCI from those with regular cognitive functioning most prominently. In this bachelors thesis I investigate whether psychotic symptoms increase the risk of decline in cognitive functions towards MCI and dementia in older adults. Methods: Literature was searched from an online database PubMed with entries "dementia AND delusions" and "Alzheimer's disease AND delusions". The final material consists of two reviews and five research articles. Results: In the light of research literature, psychotic symptoms increase the risk of dementia in older adults treefold in comparison with older adults with regular cognitive functioning. Different psychotic symptoms have different relations. Visual hallucinations increase the risk of decline in cognitive functioning, whereas both delusions and hallucinations increase the risk of dementia. The risk of dementia increases as the number of psychotic symptoms increases. The psychotic symptoms increase the risk of dementia independently of cognitive functioning. Dementia related psychotic symptoms can appear before cognitive impairment. This backs up the hypothesis that dementia related neuropsychiatric symptoms can arise during dementia prodrome before cognitive deficits arise. Scanning for psychotic symptoms can help detect dementias in their early phases.

Objective. Studies have shown that callous-unemotional traits in adolescents predict delinquency but only recently the moderators and mediators of this association have become of interest. The aim of this review of literature is to discuss the effects of neighborhood, witnessing violence and peers on delinquent behaviour of callous-unemotional youth. Results and conclusions. The role of the neighborhood was not unambiguous. One study found that the callous-unemotional traits were more stronly associated with delinquent behaviour in higher risk neighborhoods, another study concluded that the effects of callous-unemotional traits on delinquent behaviour was invariant across the levels of neighborhood disorder whereas third one neighborhood had an effect on the quality, not quantity, of delinquent behaviour. Witnessing violence fully mediated the relationship between callous-unemotional traits and all types of delinquency, but exposure to violence in the form of direct victimization mediated only the relationship between callous-unemotional traits and substance delinquency. Callous-unemotional traits were associated with a greater likelihood of adolescent offending in groups compared to other antisocial youth and assuming the role of a leader in the group. These results can be interpreted in the light of the callous-unemotional traits these adolescents have (i.a. lack of empathy and remorse, shallow emotions, being less sensitive to punishment, sensation-seeking). These explain their tendency towards delinquency independent of the neighborhood context and manipulation of others in group crime, among other things.

Goals: Symptom networks as a concept came to the research field only less than 10 years ago. Symptom network is a new statistical approach, where disorder’s symptoms are seen as separate mutually interacting elements, compared to predominant way of seeing symptoms as indicators of common background latent variable. There is only limited amount of reviews available on the topic. Goal of this thesis to review state of symptom network research, i.e. what and with which methodologies is researched with emphasis on the theoretical developments of the concept. At the same time possible and necessary future research avenues discussed. Methods: Thesis is literature review. Google Scholar was used as a search engine and search was done using expression ‘ “symptom network” psychology ’. Only research published after 2008 is included. Due to length limitations of the review, only results from two first result pages were used. After this, based on the found articles references some extra inquiries were performed. Results and conclusions: Main result is that there are very promising results within existing research and statistical methods and measures start to settle. However, there is need for more versatile research, as well as for reproduction of results. Slightly worrying observation is that lion share of symptom network research is done by one research group. This thesis provided quite good overview of the research field, though it is left on slightly non-specific level.

Goals. Gambling is a universal problem, which is particularly pronounced in Finland. The problems are not limited to pathological gambling, but gambling also harms a substantial group of non-pathological gamblers, referred to as problem gamblers in research literature. The purpose of the review was to explore differences between pathological and non-pathological gamblers in three different domains: cognition, neurophysiology and personality. The goal was to create a broad picture of psychological factors differentiating pathological gamblers from others in order to improve the understanding of risk factors associated with the development of non-pathological gambling towards pathology. To achieve this, problem gamblers were included in the comparison regarding the studies which had that separate group. Methods. Research articles were searched from Google Scholar and PubMed database with the tags non-pathological gambling and pathological gambling. The inclusion criteria were comparison of pathological gamblers to non-pathological ones and that the research topic fell under one of the three domains of the review. Results and conclusions. Regarding cognition, non-pathological and pathological gamblers seem to differ on several cognitive distortions and problem gambler resemble pathological gamblers more than they do non-problem gamblers. Emotional processing might also be weaker in pathological gamblers. In the domain of neurophysiology, the functioning of many different brain areas in gambling situations may differentiate pathological gamblers from others. Additionally, dampened HPA-axel responses appear to be associated with gambling pathology. Personality-wise pathological gamblers are particularly more impulsive, but also more neurotic than others. The personality of problem gamblers resembles that of non-problem gambler than pathological gamblers. Going forward, more studies including a separate group of problem gamblers are needed because they could provide valuable information on the development gambling pathology. Societally, it is important to recognize gambling as broader problem than just pathological gambling.

It is commonly known that physical activity and exercise have a positive effect on physical and psychological health. Previous studies with adults and elderly show that exercise can maintain or even improve cognitive capacity. Due to these results researchers have studied the effects of exercise and physical activity on children’s cognitive ability. Epidemically gro-wing concern with children and adolescent obesity has also had an impact on this field of re-search. Long term effects of exercise on children’s cognitive capacity have been studied with diffe-rent exercise interventions, which are typically organized at schools. Although, exercise in-terventions seem to have some effect it is still unknown what kind of exercise has the grea-test impact. In this thesis, I will study the effect of different kinds of physical activities on children's cognitive skills. This thesis was carried out as a literature review without empirical sample. Review systematically sums up the results from empirical intervention research do-ne. Due to exercise intervention research, getting more exercise during school days seems to have a positive effect on children’s cognitive skills or at least it doesn’t have a negative one. Research is focused on rather simple aerobic exercise interventions. Although, due to some studies covered in these thesis, more diverse aerobic exercises seem to have a greater ef-fect compared to simple ones. There is also some evidence that other than aerobic exercise seem to have an impact on children’s cognitive skills. It is still quite hard to compare the ef-fectiveness of different exercise intervention types due to lack of comprehensive research.