18 resultados para Negativity

em Helda - Digital Repository of University of Helsinki


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The overlapping sound pressure waves that enter our brain via the ears and auditory nerves must be organized into a coherent percept. Modelling the regularities of the auditory environment and detecting unexpected changes in these regularities, even in the absence of attention, is a necessary prerequisite for orientating towards significant information as well as speech perception and communication, for instance. The processing of auditory information, in particular the detection of changes in the regularities of the auditory input, gives rise to neural activity in the brain that is seen as a mismatch negativity (MMN) response of the event-related potential (ERP) recorded by electroencephalography (EEG). --- As the recording of MMN requires neither a subject s behavioural response nor attention towards the sounds, it can be done even with subjects with problems in communicating or difficulties in performing a discrimination task, for example, from aphasic and comatose patients, newborns, and even fetuses. Thus with MMN one can follow the evolution of central auditory processing from the very early, often critical stages of development, and also in subjects who cannot be examined with the more traditional behavioural measures of auditory discrimination. Indeed, recent studies show that central auditory processing, as indicated by MMN, is affected in different clinical populations, such as schizophrenics, as well as during normal aging and abnormal childhood development. Moreover, the processing of auditory information can be selectively impaired for certain auditory attributes (e.g., sound duration, frequency) and can also depend on the context of the sound changes (e.g., speech or non-speech). Although its advantages over behavioral measures are undeniable, a major obstacle to the larger-scale routine use of the MMN method, especially in clinical settings, is the relatively long duration of its measurement. Typically, approximately 15 minutes of recording time is needed for measuring the MMN for a single auditory attribute. Recording a complete central auditory processing profile consisting of several auditory attributes would thus require from one hour to several hours. In this research, I have contributed to the development of new fast multi-attribute MMN recording paradigms in which several types and magnitudes of sound changes are presented in both speech and non-speech contexts in order to obtain a comprehensive profile of auditory sensory memory and discrimination accuracy in a short measurement time (altogether approximately 15 min for 5 auditory attributes). The speed of the paradigms makes them highly attractive for clinical research, their reliability brings fidelity to longitudinal studies, and the language context is especially suitable for studies on language impairments such as dyslexia and aphasia. In addition I have presented an even more ecological paradigm, and more importantly, an interesting result in view of the theory of MMN where the MMN responses are recorded entirely without a repetitive standard tone. All in all, these paradigms contribute to the development of the theory of auditory perception, and increase the feasibility of MMN recordings in both basic and clinical research. Moreover, they have already proven useful in studying for instance dyslexia, Asperger syndrome and schizophrenia.

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Empty Heavens. Georges Bataille and the Question of Religion. The dissertation explores the question of religion in the texts of Georges Bataille (1897 1962), the controversial French avant-garde writer and philosopher. Passionate about religion throughout his life, Bataille devoted to it both critical analyses and personal meditations. In this study, Bataille s multifaceted relationship to religion is interpreted as expressing a passion for radical otherness. Bataille is approached as a characteristically modern thinker who, nevertheless, questions some landmarks of modernity insofar as modernity is interpreted as a triumph of secularization. The dissertation is situated at the intersection of comparative religion and philosophy of religion. Methodologically, the study resorts to theoretical contextualization and concept analysis. Acknowledging that Bataille s writings challenge the assumptions about coherent meaning taken for granted in traditional philosophical analysis, the study also pays attention to the literary means and, in general, the performative level of Bataille s texts. The study constructs three theoretical contexts for Bataille s question of religion first of all, the interpretation of Hegel in the mid-20th century French philosophy. In the first section of the study, Bataille s uneasy relationship with Hegel as mediated by Alexandre Kojève is explored. The motivation of his question of radical otherness is argued to arise from his struggle with the Hegelian Kojèvean notion of negativity. The second context is the dialogue with the Christian mystical tradition. Starting from the analysis of two Bataillean notions, dramatization and contestation , it is argued that, firstly, Bataille s approach to radical otherness is analogous to certain procedures of mystical texts while, secondly, the function of otherness providing no firm foundation in Bataille s texts differs from its function in mystical texts. In the third section of the study, Bataille s quest for otherness is concretized by analyzing his views on otherness of other person, on violence, and on death themes that are brought together in Bataille s lasting interest in sacrifice. Bataille s understanding of sacrifice is proportioned to social scientific and philosophical discussions on sacrifice. It is argued that the commitment to the idea of sacrifice accounts for a partial failure in the Bataillean approach to otherness, the otherness of other person remaining its (at least half) blind spot. The study presents an overview of Bataille s thought on religion. It brings out Bataille s view of the paradoxical fundamental yet impossible role of otherness in the construction of human world, as well as his understanding of religious representations as both covering over and indicating this otherness. It describes Bataille s atheological mysticism as a peculiar modern form of religiosity, as an ambivalent mourning for and exaltation of fundamental loss.

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National anniversaries such as independence days demand precise coordination in order to make citizens change their routines to forego work and spend the day at rest or at festivities that provide social focus and spectacle. The complex social construction of national days is taken for granted and operates as a given in the news media, which are the main agents responsible for coordinating these planned disruptions of normal routines. This study examines the language used in the news to construct the rather unnatural idea of national days and to align people in observing them. The data for the study consist of news stories about the Fourth of July in the New York Times, sampled over 150 years and are supplemented by material from other sources and other countries. The study is multidimensional, applying concepts from pragmatics (speech acts, politeness, information structure), systemic functional linguistics (the interpersonal metafunction and the Appraisal framework) and cognitive linguistics (frames, metaphor) as well as journalism and communications to arrive at an interdisciplinary understanding of how resources for meaning are used by writers and readers of the news stories. The analysis shows that on national anniversaries, nations tend to be metaphorized as persons having birthdays, to whom politeness should be shown. The face of the nation is to be respected in the sense of identifying the nation's interests as one's own (positive face) and speaking of citizen responsibilities rather than rights (negative face). Resources are available for both positive and negative evaluations of events and participants and the newspaper deftly changes footings (Goffman 1981) to demonstrate the required politeness while also heteroglossically allowing for a certain amount of disattention and even protest - within limits, for state holidays are almost never construed as Bakhtinian festivals, as they tend to reaffirm the hierarchy rather than invert it. Celebrations are evaluated mainly for impressiveness, and for the essentially contested quality of appropriateness, which covers norms of predictability, size, audience response, aesthetics, and explicit reference to the past. Events may also be negatively evaluated as dull ("banal") or inauthentic ("hoopla"). Audiences are evaluated chiefly in terms of their enthusiasm, or production of appropriate displays for emotional response, for national days are supposed to be occasions of flooding-out of nationalistic feeling. By making these evaluations, the newspaper reinforces its powerful position as an independent critic, while at the same time playing an active role in the construction and reproduction of emotional order embodied in "the nation's birthday." As an occasion for mobilization and demonstrations of power, national days may be seen to stand to war in the relation of play to fighting (Bateson 1955). Evidence from the newspaper's coverage of recent conflicts is adduced to support this analysis. In the course of the investigation, methods are developed for analyzing large collections of newspaper content, particularly topical soft news and feature materials that have hitherto been considered less influential and worthy of study than so-called hard news. In his work on evaluation in newspaper stories, White (1998) proposed that the classic hard news story is focused on an event that threatens the social order, but news of holidays and celebrations in general does not fit this pattern, in fact its central event is a reproduction of the social order. Thus in the system of news values (Galtung and Ruge 1965), national holiday news draws on "ground" news values such as continuity and predictability rather than "figure" news values such as negativity and surprise. It is argued that this ground helps form a necessary space for hard news to be seen as important, similar to the way in which the information structure of language is seen to rely on the regular alternation of given and new information (Chafe 1994).

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This dissertation analyzes the interrelationship between death, the conditions of (wo)man s social being, and the notion of value as it emerges in the fiction of the American novelist Thomas Pynchon (1937 ). Pynchon s present work includes six novels V. (1963), The Crying of Lot 49 (1966), Gravity s Rainbow (1973), Vineland (1990), Mason & Dixon (1997), Against the Day (2006) and several short stories. Death constitues a central thematic in Pynchon s work, and it emerges through recurrent questions of mortality, suicide, mass destruction, sacrifice, afterlife, entropy, the relationship between the animate and the inanimate, and the limits of representation. In Pynchon, death is never a mere biological given (or event); it is always determined within a certain historical, cultural, and ideological context. Throughout his work, Pynchon questions the strict ontological separation of life and death by showing the relationship between this separation and social power. Conceptual divisions also reflect the relationship between society and its others, and death becomes that through which lines of social demarcation are articulated. Determined as a conceptual and social "other side", death in Pynchon forms a challenge to modern culture, and makes an unexpected return: the dead return to haunt the living, the inanimate and the animate fuse, and technoscientific attempts at overcoming and controlling death result in its re-emergence in mass destruction and ecological damage. The questioning of the ontological line also affects the structuration of Pynchon's prose, where the recurrent narrated and narrative desire to reach the limits of representation is openly associated with death. Textualized, death appears in Pynchon's writing as a sudden rupture within the textual functioning, when the "other side", that is, the bare materiality of the signifier is foregrounded. In this study, Pynchon s cultural criticism and his poetics come together, and I analyze the subversive role of death in his fiction through Jean Baudrillard s genealogy of the modern notion of death from L échange symbolique et la mort (1976). Baudrillard sees an intrinsic bond between the social repression of death in modernity and the emergence of modern political economy, and in his analysis economy and language appear as parallel systems for generating value (exchange value/ sign-value). For Baudrillard, the modern notion of death as negativity in relation to the positivity of life, and the fact that death cannot be given a proper meaning, betray an antagonistic relation between death and the notion of value. As a mode of negativity (that is, non-value), death becomes a moment of rupture in relation to value-based thinking in short, rationalism. Through this rupture emerges a form of thinking Baudrillard labels the symbolic, characterized by ambivalence and the subversion of conceptual opposites.

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Maurice Blanchot (1907-2003), the French writer and novelist, is one of the most important figures in post-war French literature and philosophy. The main intention of this study is to figure out his position and originality in the field of phenomenology. Since this thesis concentrates on the notion of vision in Blanchot s work, its primary context is the post-war discussion of the relation between seeing and thinking in France, and particularly the discussion of the conditions of non-violent vision and language. The focus will be on the philosophical conversation between Blanchot and his contemporary philosophers. The central premise is the following: Blanchot relates the criticism of vision to the criticism of the representative model of language. In this thesis, Blanchot s definition of literary language as the refusal to reveal anything is read as a reference pointing in two directions. First, to Hegel s idea of naming as negativity which reveals Being incrementally to man, and second, to Heidegger s idea of poetry as the simultaneity of revealing and withdrawal; the aim is to prove that eventually Blanchot opposes both Hegel s idea of naming as a gradual revelation of the totality of being and Heidegger s conception of poetry as a way of revealing the truth of Being. My other central hypothesis is that for Blanchot, the criticism of the privilege of vision is always related to the problematic of the exteriority. The principal intention is to trace how Blanchot s idea of language as infinity and exteriority challenges both the Hegelian idea of naming as conceptualizing things and Heidegger s concept of language as a way to truth (as aletheia). The intention is to show how Blanchot, with his concepts of fascination, resemblance and image, both affirms and challenges the central points of Heidegger s thinking on language. Blanchot s originality in, and contribution to, the discussion about the violence of vision and language is found in his answer to the question of how to approach the other by avoiding the worst violence . I claim that by criticizing the idea of language as naming both in Hegel and Heidegger, Blanchot generates an account of language which, since it neither negates nor creates Being, is beyond the metaphysical opposition between Being and non-Being.

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Comprehension of a complex acoustic signal - speech - is vital for human communication, with numerous brain processes required to convert the acoustics into an intelligible message. In four studies in the present thesis, cortical correlates for different stages of speech processing in a mature linguistic system of adults were investigated. In two further studies, developmental aspects of cortical specialisation and its plasticity in adults were examined. In the present studies, electroencephalographic (EEG) and magnetoencephalographic (MEG) recordings of the mismatch negativity (MMN) response elicited by changes in repetitive unattended auditory events and the phonological mismatch negativity (PMN) response elicited by unexpected speech sounds in attended speech inputs served as the main indicators of cortical processes. Changes in speech sounds elicited the MMNm, the magnetic equivalent of the electric MMN, that differed in generator loci and strength from those elicited by comparable changes in non-speech sounds, suggesting intra- and interhemispheric specialisation in the processing of speech and non-speech sounds at an early automatic processing level. This neuronal specialisation for the mother tongue was also reflected in the more efficient formation of stimulus representations in auditory sensory memory for typical native-language speech sounds compared with those formed for unfamiliar, non-prototype speech sounds and simple tones. Further, adding a speech or non-speech sound context to syllable changes was found to modulate the MMNm strength differently in the left and right hemispheres. Following the acoustic-phonetic processing of speech input, phonological effort related to the selection of possible lexical (word) candidates was linked with distinct left-hemisphere neuronal populations. In summary, the results suggest functional specialisation in the neuronal substrates underlying different levels of speech processing. Subsequently, plasticity of the brain's mature linguistic system was investigated in adults, in whom representations for an aurally-mediated communication system, Morse code, were found to develop within the same hemisphere where representations for the native-language speech sounds were already located. Finally, recording and localization of the MMNm response to changes in speech sounds was successfully accomplished in newborn infants, encouraging future MEG investigations on, for example, the state of neuronal specialisation at birth.

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The auditory system can detect occasional changes (deviants) in acoustic regularities without the need for subjects to focus their attention on the sound material. Deviant detection is reflected in the elicitation of the mismatch negativity component (MMN) of the event-related potentials. In the studies presented in this thesis, the MMN is used to investigate the auditory abilities for detecting similarities and regularities in sound streams. To investigate the limits of these processes, professional musicians have been tested in some of the studies. The results show that auditory grouping is already more advanced in musicians than in nonmusicians and that the auditory system of musicians can, unlike that of nonmusicians, detect a numerical regularity of always four tones in a series. These results suggest that sensory auditory processing in musicians is not only a fine tuning of universal abilities, but is also qualitatively more advanced than in nonmusicians. In addition, the relationship between the auditory change-detection function and perception is examined. It is shown that, contrary to the generally accepted view, MMN elicitation does not necessarily correlate with perception. The outcome of the auditory change-detection function can be implicit and the implicit knowledge of the sound structure can, after training, be utilized for behaviorally correct intuitive sound detection. These results illustrate the automatic character of the sensory change detection function.

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Different languages use temporal speech cues in different linguistic functions. In Finnish, speech-sound duration is used as the primary cue for the phonological quantity distinction ― i.e., a distinction between short and long phonemes. For the second-language (L2) learners of Finnish, quantity is often difficult to master if speech-sound duration plays a less important role in the phonology of their native language (L1). The present studies aimed to investigate the cortical representations for phonological quantity in native speakers and L2 users of Finnish by using behavioral and electrophysiological methods. Since long-term memory representations for different speech units have been previously shown to participate in the elicitation of the mismatch negativity (MMN) brain response, MMN was used to compare the neural representation for quantity between native speakers and L2 users of Finnish. The results of the studies suggested that native Finnish speakers' MMN response to quantity was determined by the activation of native-language phonetic prototypes rather than by phoneme boundaries. In addition, native speakers seemed to process phoneme quantity and quality independently from each other by separate brain representations. The cross-linguistic MMN studies revealed that, in native speakers of Finnish, the MMN response to duration or quantity-degree changes was enhanced in amplitude selectively in speech sounds, whereas this pattern was not observed in L2 users. Native speakers' MMN enhancement is suggested to be due to the pre-attentive activation of L1 prototypes for quantity. In L2 users, the activation of L2 prototypes or other L2 learning effects were not reflected in the MMN, with one exception. Even though L2 users failed to show native-like brain responses to duration changes in a vowel that was similar in L1 and L2, their duration MMN response was native-like for an L2 vowel with no counterpart in L1. Thus, the pre-attentive activation of L2 users' representations was determined by the degree of similarity of L2 sounds to L1 sounds. In addition, behavioral experiments suggested that the establishment of representations for L2 quantity may require several years of language exposure.

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In the present work, effects of stimulus repetition and change in a continuous stimulus stream on the processing of somatosensory information in the human brain were studied. Human scalp-recorded somatosensory event-related potentials (ERPs) and magnetoencephalographic (MEG) responses rapidly diminished with stimulus repetition when mechanical or electric stimuli were applied to fingers. On the contrary, when the ERPs and multi-unit a ctivity (MUA) were directly recorded from the primary (SI) and secondary (SII) somatosensory cortices in a monkey, there was no marked decrement in the somatosensory responses as a function of stimulus repetition. These results suggest that this rate effect is not due to the response diminution in the SI and SII cortices. Obviously the responses to the first stimulus after a long "silent" period are nhanced due to unspecific initial orientation, originating in more broadly distributed and/or deeper neural structures, perhaps in the prefrontal cortices. With fast repetition rates not only the late unspecific but also some early specific somatosensory ERPs were diminished in amplitude. The fast decrease of the ERPs as a function of stimulus repetition is mainly due to the disappearance of the orientation effect and with faster repetition rates additively due to stimulus specific refractoriness. A sudden infrequent change in the continuous stimulus stream also enhanced somatosensory MEG responses to electric stimuli applied to different fingers. These responses were quite similar to those elicited by the deviant stimuli alone when the frequent standard stimuli were omitted. This enhancement was obviously due to the release from refractoriness because the neural structures generating the responses to the infrequent deviants had more time to recover from the refractoriness than the respective structures for the standards. Infrequent deviant mechanical stimuli among frequent standard stimuli also enhanced somatosensory ERPs and, in addition, they elicited a new negative wave which did not occur in the deviants-alone condition. This extra negativity could be recorded to deviations in the stimulation site and in the frequency of the vibratory stimuli. This response is probably a somatosensory analogue of the auditory mismatch negativity (MMN) which has been suggested to reflect a neural mismatch process between the sensory input and the sensory memory trace.

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Cognitive impairments of attention, memory and executive functions are a fundamental feature of the pathophysiology of schizophrenia. The neurophysiological and neurochemical changes in the auditory cortex are shown to underlie cognitive impairmentsin schizophrenia patients. Functional state of the neural substrate of auditory information processing could be objectively and non-invasively probed with auditory event-related potentials (ERPs) and event- related fields (ERFs). In the current work, we explored the neurochemical effect on the neural origins of auditory information processing in relation to schizophrenia. By means of ERPs/ERFs we aimed to determine how neural substrates of auditory information processing are modulated by antipsychotic medication in schizophrenia spectrum patients (Studies I, II) and by neuropharmacological challenges in healthy human subjects (Studies III, IV). First, with auditory ERPs we investigated the effects of olanzapine (Study I) and risperidone (Study II) in a group of patients with schizophrenia spectrum disorders. After 2 and 4 weeks of treatment, olanzapine has no significant effects on mismatch negativity(MMN) and P300, which, as it has been suggested, respectively reflect preattentive and attention-dependent information processing. After 2 weeks of treatment, risperidone has no significant effect on P300, however risperidone reduces P200 amplitude. This latter effect of risperidone on neural resources responsible for P200 generation could be partly explained through the action of dopamine. Subsequently, we used simultaneous EEG/MEG to investigate the effects of memantine (Study III) and methylphenidate (Study IV) in healthy subjects. We found that memantine modulates MMN response without changing other ERP components. This could be interpreted as being due to the possible influence of memantine through the NMDA receptors on auditory change- detection mechanism, with processing of auditory stimuli remaining otherwise unchanged. Further, we found that methylphenidate does not modulate the MMN response. This finding could indicate no association between catecholaminergic activities and electrophysiological measures of preattentive auditory discrimination processes reflected in the MMN. However, methylphenidate decreases the P200 amplitudes. This could be interpreted as a modulation of auditory information processing reflected in P200 by dopaminergic and noradrenergic systems. Taken together, our set of studies indicates a complex pattern of neurochemical influences produced by the antipsychotic drugs in the neural substrate of auditory information processing in patients with schizophrenia spectrum disorders and by the pharmacological challenges in healthy subjects studied with ERPs and ERFs.

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The early detection of hearing deficits is important to a child's development. However, examining small children with behavioural methods is often difficult. Research with ERPs (event-related potentials), recorded with EEG (electroencephalography), does not require attention or action from the child. Especially in children's ERP research, it is essential that the duration of a recording session is not too long. A new, faster optimum paradigm has been developed to record MMN (mismatch negativity), where ERPs to several sound features can be recorded in one recording session. This substantially shortens the time required for the experiment. So far, the new paradigm has been used in adult and school-aged children research. This study examines if MMN, LDN (late discriminative negativity) and P3a components can be recorded in two-year-olds with the new paradigm. The standard stimulus (p=0.50) was an 80 dB harmonic tone consisting of three harmonic frequencies (500 Hz, 1000 Hz and 1500 Hz) with a duration of 200 ms. The loudness deviants (p=0.067) were at a level of +6 dB or -6 dB compared to the standards. The frequency deviants (p=0.112) had a fundamental frequency of 550 or 454.4 Hz (small deviation), 625 or 400 Hz (medium deviation) or 750 or 333.3 Hz (large deviation). The duration deviants (p=0.112) had a duration of 175 ms (small deviation), 150 ms (medium deviation) or 100 ms (large deviation). The direction deviants (p=0.067) were presented from the left or right loudspeaker only. The gap deviant (p=0.067) included a 5-ms silent gap in the middle of the sound. Altogether 17 children participated in the experiment, of whom the data of 12 children was used in the analysis. ERP components were observed for all deviant types. The MMN was significant for duration and gap deviants. The LDN was significant for the large duration deviant and all other deviant types. No significant P3a was observed. These results indicate that the optimum paradigm can be used with two-year-olds. With this paradigm, data on several sound features can be recorded in a shorter time than with the previous paradigms used in ERP research.

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The German philosopher G.W.F.Hegel (1770–1831) is best known for his idealistic system philosophy, his concept of spirit [Geist] and for his dictum that the existing and the rational overlap. This thesis offers a new perspective: it examines the working of the concept ‘love’ in Hegel’s philosophy by looking at the contexts and function he puts it to, from his earliest writings to the very last lectures he gave. The starting point of the inquiry is that he applied the concept Liebe to different contexts for different purposes, but each time to provide an answer to a specific philosophical problem. His formulation, reformulation and use of ‘love’ give possible solutions to problems the solving of which was crucial to the development of his thought as a whole. The study is divided into three parts, each analysing the different problems and solutions to which Hegel applied the concept of love. The first part, "Love, morality and ethical life", examines these interconnected themes in Hegel’s early work. The main questions he addressed during this period concerned how to unite Kant’s philosophy and the Greek ideal of the good life. In this context, the concept ‘love’ did three things. First, it served to formulate his grounding idea of the relation between unity and difference, or the manifold. Secondly, it was the key to his attempt to base an ideal folk religion on Christianity interpreted as a religion of love. Finally, it provided the means to criticise Kant’s moral philosophy. The question of the moral value of love helped Hegel to break away from Kant’s thought and develop his own theory about love and ethical life. The second part of the study, "Love and the political realm", considers the way 'Liebe' functions in connection with questions concerning the community and political life in Hegel’s work. In addition to questioning the universal applicability of the concept of recognition as a key to his theory of social relations, the chapters focus on gender politics and the way he conceptualised the gender category ‘woman’ through the concept ‘love’. Another line of inquiry is the way the figure of Antigone was used to conceptualise the differentiated spheres of action for men and women, and the part ‘love’ played in Hegel’s description of Antigone’s motives. Thirdly, Hegel’s analogy of the family and the state and the way ‘love’ functions in an attempt to promote understanding of the relation between citizens and the state are examined. The third and final part of the study, "Love as absolute spirit", focuses on ‘love’ within Hegel’s systemic thought and the way he continued to characterise Geist through the language of Liebe up until and including his very last works. It is shown how Liebe functions in his hierarchical organisation of the domains of art, religion and philosophy, and how both art and religion end up in similar structural positions with regard to philosophy. One recurrent theme in the third part is Hegel’s complex relation to Romantic thought. Another line of investigation is how he reconstructed Christianity as a religion of love in his mature work. In striking contrast to his early thought, in his last works Hegel introduced a new concept of love that incorporated negativity, and that could also function as the root of political action.

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Diffuse large B-cell lymphoma (DLBCL) is the most common of the non-Hodgkin lymphomas. As DLBCL is characterized by heterogeneous clinical and biological features, its prognosis varies. To date, the International Prognostic Index has been the strongest predictor of outcome for DLBCL patients. However, no biological characters of the disease are taken into account. Gene expression profiling studies have identified two major cell-of-origin phenotypes in DLBCL with different prognoses, the favourable germinal centre B-cell-like (GCB) and the unfavourable activated B-cell-like (ABC) phenotypes. However, results of the prognostic impact of the immunohistochemically defined GCB and non-GCB distinction are controversial. Furthermore, since the addition of the CD20 antibody rituximab to chemotherapy has been established as the standard treatment of DLBCL, all molecular markers need to be evaluated in the post-rituximab era. In this study, we aimed to evaluate the predictive value of immunohistochemically defined cell-of-origin classification in DLBCL patients. The GCB and non-GCB phenotypes were defined according to the Hans algorithm (CD10, BCL6 and MUM1/IRF4) among 90 immunochemotherapy- and 104 chemotherapy-treated DLBCL patients. In the chemotherapy group, we observed a significant difference in survival between GCB and non-GCB patients, with a good and a poor prognosis, respectively. However, in the rituximab group, no prognostic value of the GCB phenotype was observed. Likewise, among 29 high-risk de novo DLBCL patients receiving high-dose chemotherapy and autologous stem cell transplantation, the survival of non-GCB patients was improved, but no difference in outcome was seen between GCB and non-GCB subgroups. Since the results suggested that the Hans algorithm was not applicable in immunochemotherapy-treated DLBCL patients, we aimed to further focus on algorithms based on ABC markers. We examined the modified activated B-cell-like algorithm based (MUM1/IRF4 and FOXP1), as well as a previously reported Muris algorithm (BCL2, CD10 and MUM1/IRF4) among 88 DLBCL patients uniformly treated with immunochemotherapy. Both algorithms distinguished the unfavourable ABC-like subgroup with a significantly inferior failure-free survival relative to the GCB-like DLBCL patients. Similarly, the results of the individual predictive molecular markers transcription factor FOXP1 and anti-apoptotic protein BCL2 have been inconsistent and should be assessed in immunochemotherapy-treated DLBCL patients. The markers were evaluated in a cohort of 117 patients treated with rituximab and chemotherapy. FOXP1 expression could not distinguish between patients, with favourable and those with poor outcomes. In contrast, BCL2-negative DLBCL patients had significantly superior survival relative to BCL2-positive patients. Our results indicate that the immunohistochemically defined cell-of-origin classification in DLBCL has a prognostic impact in the immunochemotherapy era, when the identifying algorithms are based on ABC-associated markers. We also propose that BCL2 negativity is predictive of a favourable outcome. Further investigational efforts are, however, warranted to identify the molecular features of DLBCL that could enable individualized cancer therapy in routine patient care.

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Background: Opiod dependence is a chronic severe brain disorder associated with enormous health and social problems. The relapse back to opioid abuse is very high especially in early abstinence, but neuropsychological and neurophysiological deficits during opioid abuse or soon after cessation of opioids are scarcely investigated. Also the structural brain changes and their correlations with the length of opioid abuse or abuse onset age are not known. In this study the cognitive functions, neural basis of cognitive dysfunction, and brain structural changes was studied in opioid-dependent patients and in age and sex matched healthy controls. Materials and methods: All subjects participating in the study, 23 opioid dependents of whom, 15 were also benzodiazepine and five cannabis co-dependent and 18 healthy age and sex matched controls went through Structured Clinical Interviews (SCID) to obtain DSM-IV axis I and II diagnosis and to exclude psychiatric illness not related to opioid dependence or personality disorders. Simultaneous magnetoencephalography (MEG) and electroencephalography (EEG) measurements were done on 21 opioid-dependent individuals on the day of hospitalization for withdrawal therapy. The neural basis of auditory processing was studied and pre-attentive attention and sensory memory were investigated. During the withdrawal 15 opioid-dependent patients participated in neuropsychological tests, measuring fluid intelligence, attention and working memory, verbal and visual memory, and executive functions. Fifteen healthy subjects served as controls for the MEG-EEG measurements and neuropsychological assessment. The brain magnetic resonance imaging (MRI) was obtained from 17 patients after approximately two weeks abstinence, and from 17 controls. The areas of different brain structures and the absolute and relative volumes of cerebrum, cerebral white and gray matter, and cerebrospinal fluid (CSF) spaces were measured and the Sylvian fissure ratio (SFR) and bifrontal ratio were calculated. Also correlation between the cerebral measures and neuropsychological performance was done. Results: MEG-EEG measurements showed that compared to controls the opioid-dependent patients had delayed mismatch negativity (MMN) response to novel sounds in the EEG and P3am on the contralateral hemisphere to the stimulated ear in MEG. The equivalent current dipole (ECD) of N1m response was stronger in patients with benzodiazepine co-dependence than those without benzodiazepine co-dependence or controls. In early abstinence the opioid dependents performed poorer than the controls in tests measuring attention and working memory, executive function and fluid intelligence. Test results of the Culture Fair Intelligence Test (CFIT), testing fluid intelligence, and Paced Auditory Serial Addition Test (PASAT), measuring attention and working memory correlated positively with the days of abstinence. MRI measurements showed that the relative volume of CSF was significantly larger in opioid dependents, which could also be seen in visual analysis. Also Sylvian fissures, expressed by SFR were wider in patients, which correlated negatively with the age of opioid abuse onset. In controls the relative gray matter volume had a positive correlation with composite cognitive performance, but this correlation was not found in opioid dependents in early abstinence. Conclusions: Opioid dependents had wide Sylvian fissures and CSF spaces indicating frontotemporal atrophy. Dilatation of Sylvian fissures correlated with the abuse onset age. During early withdrawal cognitive performance of opioid dependents was impaired. While intoxicated the pre-attentive attention to novel stimulus was delayed and benzodiazepine co-dependence impaired sound detection. All these changes point to disturbances on frontotemporal areas.