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Risto Näätänen - One of the best experts on this subject based on the ideXlab platform.

  • Mismatch Negativity mmn as biomarker predicting psychosis in clinically at risk individuals
    Biological Psychology, 2016
    Co-Authors: Risto Näätänen, Juanita Todd, Ulrich Schall
    Abstract:

    The early detection of young people at-risk of developing a severe mental illness like schizophrenia offers the opportunity of introducing treatment earlier than currently possible. There is some evidence that early intervention improves prognosis and functional outcome, or even prevents the full clinical manifestation of the condition in some individuals. A key prerequisite to facilitate early intervention would be a biomarker that can reliably predict a transition to schizophrenia. A smaller event-related Mismatch Negativity (MMN) potential has emerged as one of the most robust psychophysiological finding in schizophrenia akin of a biomarker of the condition. More recent research further demonstrates that MMN, but also P3a amplitudes, are already reduced in the prodromal phase of illness. Several lines of pre-clinical and clinical research support this notion and are reviewed in this article together with current obstacles, which are still limiting the translation of MMN as a biomarker into clinical practice.

  • Mismatch Negativity mmn deficiency a break through biomarker in predicting psychosis onset
    International Journal of Psychophysiology, 2015
    Co-Authors: Risto Näätänen, Tetsuya Shiga, Satoko Asano, Hirooki Yabe
    Abstract:

    Currently, the Mismatch Negativity (MMN) deficit is one of the most robust and replicable findings in schizophrenia, reflecting cognitive and functional decline, psychosocial and socio-occupational impairment, and executive dysfunction in these patients. An important break-through has very recently taken place here in the prediction of conversion to psychosis when the MMN in particular to change in tone duration was recorded in clinically at risk-mental state (ARMS) individuals. Attenuations in the MMN in these patients may be very useful in helping clinicians determine who are most likely to develop a psychotic disorder, as we will review in the present article.

  • Mismatch Negativity (MMN) as an Index of Cognitive Dysfunction
    Brain Topography, 2014
    Co-Authors: Risto Näätänen, Elyse Sussman, Dean Salisbury, Valerie Shafer
    Abstract:

    Cognition is often affected in a variety of neuropsychiatric, neurological, and neurodevelopmental disorders. The neural discriminative response, reflected in Mismatch Negativity (MMN) and its magnetoencephalographic equivalent (MMNm), has been used as a tool to study a variety of disorders involving auditory cognition. MMN/MMNm is an involuntary brain response to auditory change or, more generally, to pattern regularity violation. For a number of disorders, MMN/MMNm amplitude to sound deviance has been shown to be attenuated or the peak-latency of the component prolonged compared to controls. This general finding suggests that while not serving as a specific marker to any particular disorder, MMN may be useful for understanding factors of cognition in various disorders, and has potential to serve as an indicator of risk. This review presents a brief history of the MMN, followed by a description of how MMN has been used to index auditory processing capability in a range of neuropsychiatric, neurological, and neurodevelopmental disorders. Finally, we suggest future directions for research to further enhance our understanding of the neural substrate of deviance detection that could lead to improvements in the use of MMN as a clinical tool.

  • Mismatch Negativity is a breakthrough biomarker for understanding and treating psychotic disorders
    Proceedings of the National Academy of Sciences of the United States of America, 2013
    Co-Authors: Gregory A Light, Risto Näätänen
    Abstract:

    As neuropsychiatry continues the quest to improve the diagnosis and treatment of serious mental illnesses, important converging findings are beginning to take place in psychosis research with EEG-based biomarkers. Although patients with schizophrenia and related psychotic illnesses show many neurobiological abnormalities that distinguish them from healthy volunteers, the identification of these abnormalities has seldom led to tests with clinical utility, contributing to the critical need for a paradigm shift in our approach toward studying and treating these disorders (1, 2). It has been suggested that the development of next-generation therapeutics has been disappointing, due in part to a dearth of cognitive paradigms with cross-species translational validity (3) and biomarkers that can inform diagnosis or treatment. Here we propose that Mismatch Negativity (MMN)—a neurophysiological measure of central auditory system functioning—may be informative in developing the next generation of neuroscience-guided cognitive-enhancing treatments.

  • the Mismatch Negativity an index of cognitive decline in neuropsychiatric and neurological diseases and in ageing
    Brain, 2011
    Co-Authors: Teija Kujala, Risto Näätänen, Kairi Kreegipuu, Synnove Carlson, Carles Escera, Torsten Baldeweg
    Abstract:

    Cognitive impairment is a core element shared by a large number of different neurological and neuropsychiatric diseases. Irrespective of their different aetiologies and symptomatologies, most appear to converge at the functional deficiency of the auditory-frontal cortex network of auditory discrimination, which indexes cognitive impairment shared by these abnormalities. This auditory-frontal cortical deficiency, and hence cognitive decline, can now be objectively measured with the Mismatch Negativity and its magnetic equivalent. The auditory-frontal cortical network involved seems, therefore, to play a pivotal, unifying role in the different abnormalities. It is, however, more likely that the dysfunction that can be detected with the Mismatch Negativity and its magnetoencephalographic equivalent manifests a more widespread brain disorder, namely, a deficient N -methyl-d-aspartate receptor function, shared by these abnormalities and accounting for most of the cognitive decline. * Abbreviation : MMN : Mismatch Negativity

Teija Kujala - One of the best experts on this subject based on the ideXlab platform.

  • Low-level neural auditory discrimination dysfunctions in specific language impairment—A review on Mismatch Negativity findings
    Elsevier, 2017
    Co-Authors: Teija Kujala, Miika Leminen
    Abstract:

    In specific language impairment (SLI), there is a delay in the child’s oral language skills when compared with nonverbal cognitive abilities. The problems typically relate to phonological and morphological processing and word learning. This article reviews studies which have used Mismatch Negativity (MMN) in investigating low-level neural auditory dysfunctions in this disorder. With MMN, it is possible to tap the accuracy of neural sound discrimination and sensory memory functions. These studies have found smaller response amplitudes and longer latencies for speech and non-speech sound changes in children with SLI than in typically developing children, suggesting impaired and slow auditory discrimination in SLI. Furthermore, they suggest shortened sensory memory duration and vulnerability of the sensory memory to masking effects. Importantly, some studies reported associations between MMN parameters and language test measures. In addition, it was found that language intervention can influence the abnormal MMN in children with SLI, enhancing its amplitude. These results suggest that the MMN can shed light on the neural basis of various auditory and memory impairments in SLI, which are likely to influence speech perception. Keywords: Specific language impairment, Auditory processing, Mismatch Negativity (MMN

  • atypical central auditory speech sound discrimination in children who stutter as indexed by the Mismatch Negativity
    Journal of Fluency Disorders, 2014
    Co-Authors: Eira Janssonverkasalo, Kurt Eggers, Anu Jarvenpaa, Kalervo Suominen, Bea Van Den Bergh, Luc F De Nil, Teija Kujala
    Abstract:

    Abstract Purpose Recent theoretical conceptualizations suggest that disfluencies in stuttering may arise from several factors, one of them being atypical auditory processing. The main purpose of the present study was to investigate whether speech sound encoding and central auditory discrimination, are affected in children who stutter (CWS). Methods Participants were 10 CWS, and 12 typically developing children with fluent speech (TDC). Event-related potentials (ERPs) for syllables and syllable changes [consonant, vowel, vowel-duration, frequency (F0), and intensity changes], critical in speech perception and language development of CWS were compared to those of TDC. Results There were no significant group differences in the amplitudes or latencies of the P1 or N2 responses elicited by the standard stimuli. However, the Mismatch Negativity (MMN) amplitude was significantly smaller in CWS than in TDC. For TDC all deviants of the linguistic multifeature paradigm elicited significant MMN amplitudes, comparable with the results found earlier with the same paradigm in 6-year-old children. In contrast, only the duration change elicited a significant MMN in CWS. Conclusions The results showed that central auditory speech-sound processing was typical at the level of sound encoding in CWS. In contrast, central speech-sound discrimination, as indexed by the MMN for multiple sound features (both phonetic and prosodic), was atypical in the group of CWS. Findings were linked to existing conceptualizations on stuttering etiology. Educational objectives: The reader will be able (a) to describe recent findings on central auditory speech-sound processing in individuals who stutter, (b) to describe the measurement of auditory reception and central auditory speech-sound discrimination, (c) to describe the findings of central auditory speech-sound discrimination, as indexed by the Mismatch Negativity (MMN), in children who stutter.

  • the Mismatch Negativity an index of cognitive decline in neuropsychiatric and neurological diseases and in ageing
    Brain, 2011
    Co-Authors: Teija Kujala, Risto Näätänen, Kairi Kreegipuu, Synnove Carlson, Carles Escera, Torsten Baldeweg
    Abstract:

    Cognitive impairment is a core element shared by a large number of different neurological and neuropsychiatric diseases. Irrespective of their different aetiologies and symptomatologies, most appear to converge at the functional deficiency of the auditory-frontal cortex network of auditory discrimination, which indexes cognitive impairment shared by these abnormalities. This auditory-frontal cortical deficiency, and hence cognitive decline, can now be objectively measured with the Mismatch Negativity and its magnetic equivalent. The auditory-frontal cortical network involved seems, therefore, to play a pivotal, unifying role in the different abnormalities. It is, however, more likely that the dysfunction that can be detected with the Mismatch Negativity and its magnetoencephalographic equivalent manifests a more widespread brain disorder, namely, a deficient N -methyl-d-aspartate receptor function, shared by these abnormalities and accounting for most of the cognitive decline. * Abbreviation : MMN : Mismatch Negativity

  • the Mismatch Negativity in cognitive and clinical neuroscience theoretical and methodological considerations
    Biological Psychology, 2007
    Co-Authors: Teija Kujala, Mari Tervaniemi, Erich Schroger
    Abstract:

    Mismatch Negativity (MMN) component of the event-related brain potentials has become popular in cognitive and clinical brain research during the recent years. It is an early response to a violation of an auditory rule such as an infrequent change in the physical feature of a repetitive sound. There is a lot of evidence on the association of the MMN parameters and behavioral discrimination ability, although this relationship is not always straight-forward. Since the MMN reflects sound discrimination accuracy, it can be used for probing how well different groups of individuals perceive sound differences, and how training or remediation affects this ability. In the present review, we first introduce some of the essential MMN findings in probing sound discrimination, memory, and their deficits. Thereafter, issues which need to be taken into account in MMN investigations as well as new improved recording paradigms are discussed.

  • auditory sensory memory disorder in dyslexic adults as indexed by the Mismatch Negativity
    European Journal of Neuroscience, 2003
    Co-Authors: Teija Kujala, Mari Tervaniemi, S Belitz, Risto Näätänen
    Abstract:

    Deficient temporal discrimination and vulnerability to masking effects caused by rapidly succeeding or simultaneous sounds might be one factor underlying the phonological difficulties in dyslexia. We evaluated cortical auditory discrimination in dyslexia by recording the Mismatch Negativity (MMN) for a simple pitch change, for an order reversal of tone pairs, and for tone-pair order reversals, with a third tone either preceding or following the tone pairs. It was found that when an additional tone followed the pairs the MMN amplitude was attenuated, suggesting elevated backward-masking effects in the auditory cortex of dyslexic individuals. In addition, the MMN elicited by pitch change was diminished over the left hemisphere of the dyslexic individuals suggesting left hemisphere auditory dysfunction. These results suggest impaired cortical discrimination of sounds and lowered tolerance for the masking effects of rapidly following sounds in dyslexia.

Kimmo Alho - One of the best experts on this subject based on the ideXlab platform.

  • the Mismatch Negativity mmn in basic research of central auditory processing a review
    Clinical Neurophysiology, 2007
    Co-Authors: Risto Näätänen, Teemu Rinne, Petri Paavilainen, Kimmo Alho
    Abstract:

    In the present article, the basic research using the Mismatch Negativity (MMN) and analogous results obtained by using the magnetoencephalography (MEG) and other brain-imaging technologies is reviewed. This response is elicited by any discriminable change in auditory stimulation but recent studies extended the notion of the MMN even to higher-order cognitive processes such as those involving grammar and semantic meaning. Moreover, MMN data also show the presence of automatic intelligent processes such as stimulus anticipation at the level of auditory cortex. In addition, the MMN enables one to establish the brain processes underlying the initiation of attention switch to, conscious perception of, sound change in an unattended stimulus stream.

  • memory traces for words as revealed by the Mismatch Negativity
    NeuroImage, 2001
    Co-Authors: Friedemann Pulvermuller, Teija Kujala, Risto J Ilmoniemi, Yury Shtyrov, Kimmo Alho, Hannu Tiitinen, Jaana Simola, Paavo Alku, S Martinkauppi, Risto Näätänen
    Abstract:

    Brain responses to the same spoken syllable completing a Finnish word or a pseudo-word were studied. Native Finnish-speaking subjects were instructed to ignore the sound stimuli and watch a silent movie while the Mismatch Negativity (MMN), an automatic index of experience-dependent auditory memory traces, was recorded. The MMN to each syllable was larger when it completed a word than when it completed a pseudo-word. This enhancement, reaching its maximum amplitude at about 150 ms after the word's recognition point, did not occur in foreign subjects who did not know any Finnish. These results provide the first demonstration of the presence of memory traces for individual spoken words in the human brain. Using whole-head magnetoencephalography, the major intracranial source of this word-related MMN was found in the left superior temporal lobe.

  • separate time behaviors of the temporal and frontal Mismatch Negativity sources
    NeuroImage, 2000
    Co-Authors: Teemu Rinne, Risto Näätänen, Risto J Ilmoniemi, Kimmo Alho, Juha Virtanen
    Abstract:

    It has been proposed that Mismatch Negativity (MMN) is generated by temporal and frontal lobe sources, the former being associated with change detection and the latter with involuntary switching of attention to sound change. If this switching of attention is triggered by the temporal cortex change-detection mechanism, one would expect that the frontal component of MMN is activated later than the temporal one. This was studied by using 64-channel electroencephalography (EEG) and 122-channel magnetoencephalography (MEG) with realistically shaped head models to determine the source current distribution in different lobes as a function of time. Minimum-norm estimation (MNE) was performed, constraining the solution to the reconstructed cortical sheet. The results support the hypothesis that the frontal MMN generator is activated later than the auditory cortex generator.

  • cerebral generators of Mismatch Negativity mmn and its magnetic counterpart mmnm elicited by sound changes
    Ear and Hearing, 1995
    Co-Authors: Kimmo Alho
    Abstract:

    Infrequent (“deviant”) sounds occurring in a sequence of repetitive (“standard”) sounds elicit an event-related brain potential (ERP) response called the Mismatch Negativity (MMN) even in the absence of attention to these sounds. MMN appears to be caused by a neuronal Mismatch between the deviant au

  • Mismatch Negativity a unique measure of sensory processing in audition
    International Journal of Neuroscience, 1995
    Co-Authors: Risto Näätänen, Kimmo Alho
    Abstract:

    Physically deviant auditory stimuli occurring among frequent (“standard”) stimuli (e.g., tones or phonetic stimuli) elicit the Mismatch Negativity (MMN) of the auditory event-related potential (ERP). The MMN is presumably generated by a Mismatch process between the sensory input from a deviant stimulus and a neural sensory-memory trace representing the physical features of the standard stimulus. This process, as well as sensory analysis of auditory input and its encoding into the memory trace, appear to be automatic since the MMN is elicited even by changes in unattended auditory stimuli. Therefore the MMN indirectly provides a unique, objective measure of the central representation of a sound. This opens new possibilities for basic research as well as clinical and other applications.

Bob Oranje - One of the best experts on this subject based on the ideXlab platform.

  • auditory processing in autism spectrum disorder Mismatch Negativity deficits
    Autism Research, 2017
    Co-Authors: Chantal Vlaskamp, Bob Oranje, Birte Glenthøj, Gitte Madsen, Jens Richardt Mollegaard Jepsen, Sarah Durston, Cathriona Cantio, Niels Bilenberg
    Abstract:

    Children with autism spectrum disorders (ASD) often show changes in (automatic) auditory processing. Electrophysiology provides a method to study auditory processing, by investigating event-related potentials such as Mismatch Negativity (MMN) and P3a-amplitude. However, findings on MMN in autism are highly inconsistent, partly due to small sample sizes in the studies and differences in MMN paradigms. Therefore, in the current study, MMN and P3a amplitude were assessed in a relatively large sample of children with ASD, using a more extensive MMN paradigm and compared with that of typically developing children (TDC). Thirty-five children (aged 8–12 years) with ASD and 38 age and gender matched TDC were assessed with a MMN paradigm with three types of deviants, i.e., frequency, duration and a combination of these two. MMN elicited by duration and frequency-duration deviants was significantly reduced in the ASD group. P3a-amplitude elicited by duration deviants was significantly increased in the ASD group. Reduced MMN in children with ASD suggests that children with ASD may be less responsive to environmentally deviant stimuli at an early (sensory) level. P3a-amplitude was increased in ASD, implying a hyper-responsivity at the attentional level. In addition, as similar MMN deficits are found in schizophrenia, these MMN results may explain some of the frequently reported increased risk of children with ASD to develop schizophrenia later in life. Autism Res 2017, 10: 1857–1865. © 2017 International Society for Autism Research, Wiley Periodicals, Inc. Lay Summary Automatic detection of deviant sounds in the environment, such as upcoming traffic, is often affected in children with autism spectrum disorders (ASD). Mismatch Negativity (MMN) is a way to quantify automatic deviancy detection, using electroencephalography. In this study, auditory MMN was assessed in 35 children with ASD and 38 matched control children, revealing significantly reduced MMN in the ASD group. This may indicate that children with ASD are less able to automatically detect environmentally deviant stimuli.

  • effects of blocking d2 d3 receptors on Mismatch Negativity and p3a amplitude of initially antipsychotic naive first episode schizophrenia patients
    The International Journal of Neuropsychopharmacology, 2016
    Co-Authors: Signe During, Bob Oranje, Birte Glenthøj
    Abstract:

    Background: Reduced Mismatch Negativity and P3a amplitude have been suggested to be among the core deficits in schizophrenia since the late 1970s. Blockade of dopamine D2 receptors play an important role in the treatment of schizophrenia. In addition, there is some evidence indicating that deficits in Mismatch Negativity and P3a amplitude are related to increased dopaminergic activity. This is the first study investigating the effect of amisulpride, a potent D2-antagonist, on Mismatch Negativity and P3a amplitude in a large group of antipsychotic-naive, first-episode schizophrenia patients. Methods: Fifty-one antipsychotic-naive, first-episode schizophrenia patients were tested in a Mismatch Negativity paradigm at baseline and after 6 weeks of treatment with amisulpride. We further examined 48 age- and gender-matched controls in this paradigm. Results: At baseline, the patients showed significantly reduced P3a amplitude compared with healthy controls, but no differences in Mismatch Negativity. Although the treatment with amisulpride significantly improved the patients’ psychopathological (PANSS) and functional (GAF) scores, it did not influence their Mismatch Negativity amplitude, while also their reduced P3a amplitude persisted. Conclusion: Our findings show that antipsychotic naive, first-episode patients with schizophrenia have normal Mismatch Negativity yet reduced P3a amplitude compared with healthy controls. In spite of the fact that the 6-week amisulpride treatment improved the patients both clinically and functionally, it had no effect on either Mismatch Negativity or P3a amplitude. This suggests that even though there is a dopaminergic involvement in global functioning and symptomatology in schizophrenia, there is no such involvement in these particular measures of early information processing.

Taro Maeda - One of the best experts on this subject based on the ideXlab platform.