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The uncertain element [chapter]

Maiju Tanninen, Turo-Kimmo Lehtonen, Minna Ruckenstein
2022 Climate, Society and Elemental Insurance  
Thus, private health and life insurance policies are often seen as a form of 'extra security' that 'supplement' the structures provided by the welfare state (Lehtonen 2014; Lehtonen & Liukko 2010) .  ... 
doi:10.4324/9781003157571-19 fatcat:5545dy3n3vgvdieryu7u2wstwa

Tracking lives, forging markets

Maiju Tanninen, Turo-Kimmo Lehtonen, Minna Ruckenstein
2020 Journal of Cultural Economy  
Through an insurance contract, customers gain access to a collective of people that covers the risks for the 'pool as a whole' (Lehtonen and Liukko 2015, p. 158 ).  ...  Zelizer 1979 , O'Malley 2002 , Lehtonen 2014 , McFall 2014 , Sjöblom 2016 . Our informants treated self-tracking practices as the most efficient way for companies to increase health awareness.  ... 
doi:10.1080/17530350.2020.1852949 fatcat:ovfwfy6smze7hlp6bmdvz6feh4

Metabolic alterations in Parkinson's disease astrocytes

Tuuli-Maria Sonninen, Riikka H. Hämäläinen, Marja Koskuvi, Minna Oksanen, Anastasia Shakirzyanova, Sara Wojciechowski, Katja Puttonen, Nikolay Naumenko, Gundars Goldsteins, Nihay Laham-Karam, Marko Lehtonen, Pasi Tavi (+2 others)
2020 Scientific Reports  
In Parkinson's disease (PD), the loss of dopaminergic (DA) neurons in the substantia nigra pars compacta is associated with Lewy bodies arising from the accumulation of alpha-synuclein protein which leads ultimately to movement impairment. While PD has been considered a disease of the DA neurons, a glial contribution, in particular that of astrocytes, in PD pathogenesis is starting to be uncovered. Here, we report findings from astrocytes derived from induced pluripotent stem cells of LRRK2
more » ... 9S mutant patients, with one patient also carrying a GBA N370S mutation, as well as healthy individuals. The PD patient astrocytes manifest the hallmarks of the disease pathology including increased expression of alpha-synuclein. This has detrimental consequences, resulting in altered metabolism, disturbed Ca2+ homeostasis and increased release of cytokines upon inflammatory stimulation. Furthermore, PD astroglial cells manifest increased levels of polyamines and polyamine precursors while lysophosphatidylethanolamine levels are decreased, both of these changes have been reported also in PD brain. Collectively, these data reveal an important role for astrocytes in PD pathology and highlight the potential of iPSC-derived cells in disease modeling and drug discovery.
doi:10.1038/s41598-020-71329-8 pmid:32879386 fatcat:dz73ffcfcvgfvfucn4rxlz56i4

Reality of auditory verbal hallucinations

Tuukka T. Raij, Minna Valkonen-Korhonen, Matti Holi, Sebastian Therman, Johannes Lehtonen, Riitta Hari
2009 Brain  
Distortion of the sense of reality, actualized in delusions and hallucinations, is the key feature of psychosis but the underlying neuronal correlates remain largely unknown. We studied 11 highly functioning subjects with schizophrenia or schizoaffective disorder while they rated the reality of auditory verbal hallucinations (AVH) during functional magnetic resonance imaging (fMRI). The subjective reality of AVH correlated strongly and specifically with the hallucination-related activation
more » ... gth of the inferior frontal gyri (IFG), including the Broca's language region. Furthermore, how real the hallucination that subjects experienced was depended on the hallucination-related coupling between the IFG, the ventral striatum, the auditory cortex, the right posterior temporal lobe, and the cingulate cortex. Our findings suggest that the subjective reality of AVH is related to motor mechanisms of speech comprehension, with contributions from sensory and salience-detection-related brain regions as well as circuitries related to self-monitoring and the experience of agency. Abbreviations: AVH = auditory verbal hallucination; IFG = inferior frontal gyrus; HRF = haemodynamic response function; PANSS = Positive and Negative Syndromes Scale; SRH = subjective reality of hallucinations; VAS = visual analogue scale
doi:10.1093/brain/awp186 pmid:19620178 pmcid:PMC2768657 fatcat:xhjugvmqdbghlpmjjqhrwlb5se

Neural dynamics of reading morphologically complex words

Johanna Vartiainen, Silvia Aggujaro, Minna Lehtonen, Annika Hultén, Matti Laine, Riitta Salmelin
2009 NeuroImage  
et al., 2006b; Lehtonen et al., in press) either.  ...  It builds on the two earlier studies that have sought to clarify the neural basis of Finnish morphology (EEG: Lehtonen et al., 2007 ; fMRI: Lehtonen et al., 2006b) .  ... 
doi:10.1016/j.neuroimage.2009.06.002 pmid:19520173 fatcat:yx3chomlkzfgfohqvl6jzv4yda

Editorial: Morphologically Complex Words in the Mind/Brain

Alina Leminen, Minna Lehtonen, Mirjana Bozic, Harald Clahsen
2016 Frontiers in Human Neuroscience  
The Editorial on the Research Topic Morphologically Complex Words in the Mind/Brain In most languages, sentences can be broken down into words, which themselves can be further decomposed into units that contain meaning of their own, so-called morphemes (e.g., "play" or plural form "-s"). Morphemes are the main building blocks and tools, which we use to create and change words. The representation of morphologically complex words (inflected, derived, and compound) in the mental lexicon and their
more » ... eurocognitive processing has been a vigorously investigated topic in psycholinguistics and the cognitive neuroscience of language. Are morphologically complex words such as "player" and "plays" decomposed into their constituents (i.e., into their stem "play" and plural suffix "-s" or agentive suffix "-er") or are they processed and represented holistically ("player" and "plays")? Despite extensive research, many important questions remain unanswered. Our Research Topic addresses several currently unresolved topics on the time-course of morphological analysis and the relationship between form and meaning information in morphological parsing. The studies also seek answers to the questions of how inflections and derivations differ in the way they are handled by the mental lexicon, how compound words are recognized and produced, as well as how morphologically complex words are processed within the bilingual mental lexicon, as well as by different clinical populations. With respect to time-course of morphological processing and interplay between form and meaning, many current models assume that morphological processing proceeds by analyzing form first at the very earliest stages of processing, after which meaning of the morphemes is accessed (e.g., Rastle and Davis, 2008) . In contrast, Feldman et al. provided evidence for the view that meaning information comes into play even at the very early stages of morphologically complex word recognition. Two studies (Estivalet and Meunier; Smolka et al.), focusing on the role of semantic transparency and regularity in derived and inflected words indicate decomposition in semantically and phonologically opaque and transparent words in two different languages. That is, both semantically transparent and opaque derivations were found to be represented and processed in similar ways in German (Smolka et al.), and all inflected verbal forms in French showed decomposition effects during visual recognition (Estivalet and Meunier), regardless of their regularity and phonological realization, thus supporting models of obligatory morphological decomposition (e.g., Taft, 2004) . Two neuroimaging studies in this Research Topic elucidated the neural correlates of the processing of regular vs. irregular inflection, a highly debated issue. Using time-resolved magnetoencephalography (MEG) with English verbs, Fruchter et al. found priming effects for visually presented irregular stimuli, quite early in the processing, within the left fusiform and inferior temporal regions. The results were interpreted as favoring a single mechanism account of the English past tense, in which even irregulars are decomposed into stems and affixes prior to lexical access (Stockall and Marantz, 2006) , as opposed to a dual mechanism model, in which irregulars are recognized as whole forms (e.g., Pinker, 1991). On the other hand, with Russian, Leminen et al. Editorial: Morphologically Complex Words in the Mind/Brain a language with very little scrutiny so far and a relatively novel analysis of fMRI functional connectivity, Kireev et al. reported that functional connectivity between the left inferior frontal gyrus (LIFG) and bilateral superior temporal gyri (STG) was significantly greater for regular real verbs than for irregular ones during production. The results shed new light on the functional interplay within the language-processing network and stress the role of functional temporo-frontal connectivity in complex morphological processes. These two studies with arguably different outcomes suggest that the debate on regular vs. irregular form processing continues. They however also point to the potentially critical influences of the processing modality (written vs. spoken) as well as the task (comprehension vs. production) on the mechanism of morphological processing. Turning to a question of inflected and derived word processing, where several previous studies have observed differences in the underpinning neural mechanisms (e.g., Leminen et al.; Leminen et al., 2013; Leminen et al., for a review see e.g., Bozic and Marslen-Wilson, 2010). Service and Maury report differences between derivations and inflections in working memory (as measured by simple and complex span tasks), suggesting different levels of lexical competition and hence, differential lexical storage. Using combined magneto-and electroencephalography (M/EEG), Whiting et al. defined the spatiotemporal patterns of activity that support the recognition of spoken English inflectional and derivational words. Results demonstrated that spoken complex word processing engages the left-hemisphere's fronto-temporal language network, and, importantly, does not require focused attention on the linguistic input (Whiting et al.). Using a similar auditory passive oddball paradigm and EEG, Hanna and Pulvermuller observed that the processing of spoken derived words was governed by a distributed set of bilateral temporo-parietal areas, consistent with the previous literature (Bozic et al., 2013; Leminen et al.). In addition, derived words were found to have full-form memory traces in the neural lexicon (see e.g., Clahsen et al., 2003; Bozic and Marslen-Wilson, 2010; Leminen et al.) , activated automatically (see also Leminen et al., 2013) . In the field of cognitive neuroscience of language, a largely under-investigated topic has been the neural processing of compound words. An article by Brooks and Cid da Garcia therefore brings an important contribution to elucidating this issue. Their primed word naming task revealed decompositional effects in access to both transparent and opaque compounds. In the MEG results, the left anterior temporal lobe (LATL) as well as the left posterior superior temporal gyrus showed increased activity only for the transparent compounds. These effects were concluded to be related to compositional processes and lexical-semantic retrieval, respectively. Our Research Topic also presents novel findings on written production of compounds, where Bertram et al. introduces an approach rarely used with morphologically complex words. Specifically, they investigated the interplay between central linguistic processing and peripheral motor processes during typewriting. Bertram et al. concluded that compound words seem to be retrieved as whole words before writing is initiated and that linguistic planning is not fully complete before writing, but cascades into the motor execution phase. With respect to the important topic on bilingual morphological processing, our Research Topic presents three studies and one commentary. Lensink et al. used a priming paradigm to show that both transparent (e.g., moonlight) and opaque (e.g., honeymoon) compounds in the second language (L2) undergo morphological analysis in production. The second study (De Grauwe et al.) used fMRI to assess the processing of Dutch prefixed derived words, demonstrating a priming effect for L2 speakers in the LIFG, an area that has been associated with morphological decomposition. De Grauwe et al. concluded that L2 speakers decompose transparent derived verbs rather than process them holistically. In his commentary on De Grauwe et al.'s article, Jacob discusses the specific aspect of decomposition that the LIFG finding might be reflecting, as well as the extent to which the findings can be generalized to all derivations, instead of one particular verb class. In the third article, Mulder et al. examined the role of orthography and task-related processing mechanisms in the activation of morphologically related complex words during bilingual word processing. Their study shows that the combined morphological family size is a better predictor of reaction times (RTs) than the family size of individual languages. This study also demonstrates that the effect of morphological family size is sensitive to both semantic and orthographic factors, and that it also depends on task demands. Last but not least, two studies aimed to provide insights into morphological processing by analyzing neglect and letter position issues in dyslexic population. Reznick and Friedmann suggested that the effect of morphology on reading patterns in neglexia provides supportive evidence that morphological decomposition occurs pre-lexically, in an early orthographicvisual analysis stage. Using a different dyslexic population, letter position dyslexics, Friedmann et al. reached a similar conclusion that morphological parsing takes place at an early, pre-lexical stage and that decomposition is structurally rather than lexically driven. To summarize, this Research Topic presents an overview of a wide range of questions currently addressed in the field of morphological processing. It highlights the significance of morphological information in language processing, both written and spoken, as assessed by the variety of methods and approaches presented here. The partly discrepant findings in some of the contributions to our Research Topic also underline the need for increased cross-talk between researchers using different methods, modalities, and paradigms. AUTHOR CONTRIBUTIONS AL wrote the main paper, ML and MB edited the manuscript, HC provided conceptual advice. ACKNOWLEDGMENTS
doi:10.3389/fnhum.2016.00047 pmid:26909032 pmcid:PMC4754435 fatcat:csbynu5dqnbbjnpkecr2tu3xfu

Does language switching behavior rely on general executive functions?

Jussi Jylkkä, Matti Laine, Minna Lehtonen
2020 Bilingualism: Language and Cognition  
Minna Lehtonen was supported by Academy of Finland (#288880) and Matti Laine and Jussi Jylkkä by the Abo Akademi University Endowment (the BrainTrain project and a personal grant).  ...  IP address: 207.241.227.105, on 15 Nov 2020 at 08:54:04, subject to the Cambridge Core terms of use, available at Jussi Jylkkä, Matti Laine and Minna Lehtonen https://www.cambridge.org/core/terms.  ...  IP address: 207.241.227.105, on 15 Nov 2020 at 08:54:04, subject to the Cambridge Core terms of use, available at Jussi Jylkkä, Matti Laine and Minna Lehtonen https://www.cambridge.org/core/terms.  ... 
doi:10.1017/s1366728920000619 fatcat:gyilnrfrxfaorfy3sh6rf6x4f4

Heart rate variability in acute psychosis

Minna Valkonen-Korhonen, Mika P. Tarvainen, Perttu Ranta-Aho, Pasi A. Karjalainen, Juhani Partanen, Jari Karhu, Johannes Lehtonen
2003 Psychophysiology  
Heart rate variability (HRV) provides reliable tools to assess the integrity and reactivity of autonomic nervous function. Our aim was to examine HRV in the resting condition and during different mental loads in acute psychosis compared to healthy controls. HRV was measured in 17 first-episode drug-naive patients with psychosis and 21 healthy controls during oddball tasks and while performing the Wisconsin Card Sorting Test. A discrete event series was constructed by an adaptive QRS detector
more » ... orithm and power spectrum estimation was carried out. The RMSSD (representing interval differences of successive heartbeats) and the amount of high frequency (HF) power were significantly reduced in patients. Moreover, the patients' HRV remained unaltered during the tasks, whereas in controls the HRV diminished with increasing mental load of the task. Patients with psychosis displayed less short-term HR reactivity than healthy controls. They also failed to adapt HRV according to the task-connected strain. Acute psychosis is characterized by a limited capacity to respond to external demands at the level of autonomic nervous system. Descriptors: Heart rate variability, Autonomic nervous system, Psychosis Address reprint requests to:
doi:10.1111/1469-8986.00072 pmid:14696725 fatcat:og7pk7wz4vekxo47yp742q26te

Nutritive sucking creates a neurophysiological bridge over the birth gap

Johannes Lehtonen, Minna Valkonen‐Korhonen, Pasi A. Karjalainen
2019 Acta Paediatrica  
ACKNOWLEDGEMENT The authors thank Professor Liisa Lehtonen for valuable comments on the manuscript. CONFLICTS OF INTEREST The authors have no conflicts of interest.  ... 
doi:10.1111/apa.14993 pmid:31482625 fatcat:pfnvcrqvczeaja5322wqyur2hu

Independence of Visual Awareness from the Scope of Attention: an Electrophysiological Study

Mika Koivisto, Antti Revonsuo, Minna Lehtonen
2005 Cerebral Cortex  
Recent brain imaging studies have revealed that increased neural activity along the ventral visual stream and parietal and frontal areas is associated with visual awareness. In order to study the time-course and temporal aspects of awareness, we examined electrophysiological correlates of conscious vision in two masking experiments. The differences in event-related potentials (ERPs) between unmasked (consciously recognized) and masked (unrecognized) stimuli were considered to be
more » ... ical correlates of awareness. Two attentional conditions (global, local) were included to examine the relationship between the scope of attention and awareness. Two ERP-deflections were found to correlate with awareness. First, awareness was associated with a posterior negative amplitude shift 130--320 ms after the stimulus. This effect was present in both attention conditions, suggesting that it emerges independent of the scope of attention. Second, ERPs to unmasked stimuli became more positive as compared with masked stimuli around 400 ms, peaking at parietal sites. This effect was attenuated in the local attention condition, although the participants were aware of the stimuli, suggesting that the late positivity does not directly correlate with visual awareness. The results imply that the earlier negativity is the earliest and most direct correlate of visual awareness.
doi:10.1093/cercor/bhi121 pmid:15958780 fatcat:tdtwf2hofjgvdoe7osdlomn6lu

Neural mechanisms underlying word- and phrase-level morphological parsing

Alina Leminen, Sini Jakonen, Miika Leminen, Jyrki P. Mäkelä, Minna Lehtonen
2016 Journal of Neurolinguistics  
In Finnish, greater activation of LIFG was found for inflected words than for monomorphemic words (Laine, Rinne, Krause, Ter€ as, & Sipil€ a, 1999; Lehtonen et al., 2009; Lehtonen, Vorobyev, Hugdahl,  ...  In addition to LIFG, superior temporal gyrus, and the anterior cingulate have been observed during the processing of inflected words (Bozic & Marslen-Wilson, 2010; Lehtonen et al., 2009; Lehtonen et al  ... 
doi:10.1016/j.jneuroling.2015.10.003 fatcat:noxuvvjywfav7okrxju44uy3tu

Evidence for Early Morphological Decomposition: Combining Masked Priming with Magnetoencephalography

Minna Lehtonen, Philip J. Monahan, David Poeppel
2011 Journal of Cognitive Neuroscience  
et al., 2006 Lehtonen et al., , 2007 and/or to the semantic-syntactic integration of morphemes (Leinonen et al., 2009; Vartiainen et al., 2009; Lehtonen et al., 2006 Lehtonen et al., , 2007 have been  ...  , Vorobyev, Hugdahl, Tuokkola, & Laine, 2006) or electrophysiological measures (Leinonen et al., 2009; Vartiainen et al., 2009; Lehtonen et al., 2007) .  ... 
doi:10.1162/jocn_a_00035 pmid:21557645 pmcid:PMC4465380 fatcat:ob36xcvhc5h4xhrbqmxhrsaxyu

Beyond volume: A surface-based approach to bilingualism-induced grey matter changes

Sini Hämäläinen, Juho Joutsa, Aleksi J. Sihvonen, Alina Leminen, Minna Lehtonen
2018 Neuropsychologia  
Bilingualism is a sustained experience associated with structural changes in cortical grey matter (GM) morphology. Apart from a few studies, a dominant method used to assess bilingualism-induced GM changes has been the voxel-based morphometry (VBM) analysis. While VBM is sensitive to GM volume/density differences in general, it cannot be used to identify whether the observed difference is due to relative changes in, e.g., cortical thickness, area or folding, as it uses a single combined measure
more » ... of them all. Here, we used surface-based analysis (SBA) approach to investigate whether early acquisition of a second language (L2) affects the cortical GM morphology relative to late L2 acquisition. More specifically, our aim was to test a hypothesis that early acquisition of two languages induces GM changes that are predominantly surface area-driven, while late acquisition is supposedly characterised with primarily thickness-driven changes. To this end, several surface-based measures were concurrently compared between the groups. In line with the hypothesis, the results revealed that early bilingual experience is associated with significantly extended cortical surface area over the left pars opercularis and the right superior temporal gyrus. Contrary to our expectations, however, we found no evidence supporting the postulated association between late L2 acquisition and increased cortical thickness. Nevertheless, our study highlights the importance of including cortical surface measures when investigating bilingualismrelated GM modulations.
doi:10.1016/j.neuropsychologia.2018.04.038 pmid:29727625 fatcat:2udpqh3dvnccfeowqz6hbu6sk4

Predicting Reaction Times in Word Recognition by Unsupervised Learning of Morphology [chapter]

Sami Virpioja, Minna Lehtonen, Annika Hultén, Riitta Salmelin, Krista Lagus
2011 Lecture Notes in Computer Science  
A central question in the study of the mental lexicon is how morphologically complex words are processed. We consider this question from the viewpoint of statistical models of morphology. As an indicator of the mental processing cost in the brain, we use reaction times to words in a visual lexical decision task on Finnish nouns. Statistical correlation between a model and reaction times is employed as a goodness measure of the model. In particular, we study Morfessor, an unsupervised method for
more » ... learning concatenative morphology. The results for a set of inflected and monomorphemic Finnish nouns reveal that the probabilities given by Morfessor, especially the Categories-MAP version, show considerably higher correlations to the reaction times than simple word statistics such as frequency, morphological family size, or length. These correlations are also higher than when any individual test subject is viewed as a model.
doi:10.1007/978-3-642-21735-7_34 fatcat:t6rswqvznfd2fohg6agtmhx5ba

Testing the Stem Dominance Hypothesis: Meaning Analysis of Inflected Words and Prepositional Phrases

Minna Lehtonen, Gabor Harrer, Erling Wande, Matti Laine, Kevin Paterson
2014 PLoS ONE  
Citation: Lehtonen M, Harrer G, Wande E, Laine M (2014) Testing the Stem Dominance Hypothesis: Meaning Analysis of Inflected Words and Prepositional Phrases. PLoS ONE 9(3): e93136.  ... 
doi:10.1371/journal.pone.0093136 pmid:24676218 pmcid:PMC3968051 fatcat:sv4e7rtxd5e33hjijmgmrfas7i
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