Publications by authors named "Tiina Parviainen"

39 Publications

Intensified Job Demands and Cognitive Stress Symptoms: The Moderator Role of Individual Characteristics.

Front Psychol 2021 22;12:607172. Epub 2021 Apr 22.

Department of Psychology, University of Jyväskylä, Jyväskylä, Finland.

Intensified job demands (IJDs) originate in the general accelerated pace of society and ever-changing working conditions, which subject workers to increasing workloads and deadlines, constant planning and decision-making about one's job and career, and the continual learning of new professional knowledge and skills. This study investigated how individual characteristics, namely negative and positive affectivity related to competence demands, and multitasking preference moderate the association between IJDs and cognitive stress symptoms among media workers ( = 833; 69% female, mean age 48 years). The results show that although IJDs were associated with higher cognitive stress symptoms at work, that is, difficulties in concentration, thinking clearly, decision-making, and memory, competence demands-related negative affectivity explained the most variance in cognitive stress symptoms. In addition, IJDs were more strongly associated with cognitive stress symptoms at work in individuals with high competence demand-related negative affectivity, and low multitasking preference (moderation effects). Altogether, the present findings suggest that HR practices or workplace interventions to ease employees' negative affectivity from increasing competence demands at work could usefully support employees' effective cognitive functioning when confronted with IJDs.
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http://dx.doi.org/10.3389/fpsyg.2021.607172DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8100594PMC
April 2021

Neural Mechanisms Underlying Human Auditory Evoked Responses Revealed By Human Neocortical Neurosolver.

Brain Topogr 2021 Apr 19. Epub 2021 Apr 19.

Department of Neuroscience, Carney Institute for Brain Sciences, Brown University, Providence, USA.

Auditory evoked fields (AEFs) are commonly studied, yet their underlying neural mechanisms remain poorly understood. Here, we used the biophysical modelling software Human Neocortical Neurosolver (HNN) whose foundation is a canonical neocortical circuit model to interpret the cell and network mechanisms contributing to macroscale AEFs elicited by a simple tone, measured with magnetoencephalography. We found that AEFs can be reproduced by activating the neocortical circuit through a layer specific sequence of feedforward and feedback excitatory synaptic drives, similar to prior simulation of somatosensory evoked responses, supporting the notion that basic structures and activation patterns are preserved across sensory regions. We also applied the modeling framework to develop and test predictions on neural mechanisms underlying AEF differences in the left and right hemispheres, as well as in hemispheres contralateral and ipsilateral to the presentation of the auditory stimulus. We found that increasing the strength of the excitatory synaptic cortical feedback inputs to supragranular layers simulates the commonly observed right hemisphere dominance, while decreasing the input latencies and simultaneously increasing the number of cells contributing to the signal accounted for the contralateral dominance. These results provide a direct link between human data and prior animal studies and lay the foundation for future translational research examining the mechanisms underlying alteration in this fundamental biomarker of auditory processing in healthy cognition and neuropathology.
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http://dx.doi.org/10.1007/s10548-021-00838-0DOI Listing
April 2021

Physical activity and aerobic fitness show different associations with brain processes underlying anticipatory selective visuospatial attention in adolescents.

Brain Res 2021 Feb 25;1761:147392. Epub 2021 Feb 25.

Department of Psychology, Center for Interdisciplinary Brain Research, University of Jyväskylä, Mattilanniemi 6, FI-40014 Jyväskylä, Finland.

Current knowledge about the underlying brain processes of exercise-related benefits on executive functions and the specific contributions of physical activity and aerobic fitness during adolescence is inconclusive. We explored whether and how physical activity and aerobic fitness are associated with the oscillatory dynamics underlying anticipatory spatial attention. We studied whether the link between physical exercise level and cognitive control in adolescents is mediated by task-related oscillatory activity. Magnetoencephalographic alpha oscillations during a modified Posner's cueing paradigm were measured in 59 adolescents (37 females and 22 males, 12-17 years). Accelerometer-measured physical activity and aerobic fitness (20-m shuttle run test) were used to divide the sample into higher- and lower-performing groups. The interhemispheric alpha asymmetry during selective attention was larger in the high than in the low physical activity group, but there was no difference between the high and low aerobic fitness groups. Exploratory mediation analysis suggested that anticipatory interhemispheric asymmetry mediates the association between physical activity status and drift rate in the selective attention task. Higher physical activity was related to increased cue-induced asymmetry, which in turn was associated with less efficient processing of information. Behaviorally, more physically active males showed stronger dependence on the cue, while more fit females showed more efficient processing of information. Our findings suggest that physical activity may be associated with a neural marker of anticipatory attention in adolescents. These findings might help to explain the varying results regarding the association of physical activity and aerobic fitness with attention and inhibition in adolescents.
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http://dx.doi.org/10.1016/j.brainres.2021.147392DOI Listing
February 2021

Exercise intervention protocol in children and young adults with cerebral palsy: the effects of strength, flexibility and gait training on physical performance, neuromuscular mechanisms and cardiometabolic risk factors (EXECP).

BMC Sports Sci Med Rehabil 2021 Feb 26;13(1):17. Epub 2021 Feb 26.

Neuromuscular Research Center, Faculty of Sport and Health Sciences, University of Jyväskylä, Jyväskylä, Finland.

Background: Individuals with cerebral palsy (CP) have problems in everyday tasks such as walking and climbing stairs due to a combination of neuromuscular impairments such as spasticity, muscle weakness, reduced joint flexibility and poor coordination. Development of evidence-based interventions are in pivotal role in the development of better targeted rehabilitation of CP, and thus in maintaining their motor function and wellbeing. Our aim is to investigate the efficacy of an individually tailored, multifaceted exercise intervention (EXECP) in children and young adults with CP. EXECP is composed of strength, flexibility and gait training. Furthermore, this study aims to verify the short-term retention of the adaptations three months after the end of the EXECP intervention.

Methods: Twenty-four children and young adults with spastic CP will be recruited to participate in a 9-month research project with a 3-month training intervention, consisting of two to three 90-min sessions per week. In each session, strength training for the lower limbs and trunk muscles, flexibility training for the lower limbs and inclined treadmill gait training will be performed. We will evaluate muscle strength, joint flexibility, neuromuscular and cardiometabolic parameters. A nonconcurrent multiple baseline design with two pre-tests and two post-tests all interspaced by three months is used. In addition to the CP participants, 24 typically developing age and sex-matched participants will perform the two pre-tests (i.e. no intervention) to provide normative data.

Discussion: This study has a comprehensive approach examining longitudinal effects of wide variety of variables ranging from physical activity and gross motor function to sensorimotor functions of the brain and neuromuscular and cardiometabolic parameters, providing novel information about the adaptation mechanisms in cerebral palsy. To the best of our knowledge, this is the first intervention study providing supervised combined strength, flexibility and gait training for young individuals with CP.

Trial Registration Number: ISRCTN69044459, prospectively registered (21/04/2017).
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http://dx.doi.org/10.1186/s13102-021-00242-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7908003PMC
February 2021

Physical activity and aerobic fitness in relation to local and interhemispheric functional connectivity in adolescents' brains.

Brain Behav 2021 Feb 24;11(2):e01941. Epub 2020 Dec 24.

Department of Psychology, Centre for Interdisciplinary Brain Research, University of Jyväskylä, Jyväskylä, Finland.

Introduction: Adolescents have experienced decreased aerobic fitness levels and insufficient physical activity levels over the past decades. While both physical activity and aerobic fitness are related to physical and mental health, little is known concerning how they manifest in the brain during this stage of development, characterized by significant physical and psychosocial changes. The aim of the study is to examine the associations between both physical activity and aerobic fitness with brains' functional connectivity.

Methods: Here, we examined how physical activity and aerobic fitness are associated with local and interhemispheric functional connectivity of the adolescent brain (n = 59), as measured with resting-state functional magnetic resonance imaging. Physical activity was measured by hip-worn accelerometers, and aerobic fitness by a maximal 20-m shuttle run test.

Results: We found that higher levels of moderate-to-vigorous intensity physical activity, but not aerobic fitness, were linked to increased local functional connectivity as measured by regional homogeneity in 13-16-year-old participants. However, we did not find evidence for significant associations between adolescents' physical activity or aerobic fitness and interhemispheric connectivity, as indicated by homotopic connectivity.

Conclusions: These results suggest that physical activity, but not aerobic fitness, is related to local functional connectivity in adolescents. Moreover, physical activity shows an association with a specific brain area involved in motor functions but did not display any widespread associations with other brain regions. These results can advance our understanding of the behavior-brain associations in adolescents.
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http://dx.doi.org/10.1002/brb3.1941DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7882164PMC
February 2021

Corrigendum to 'Automated detection and localization system of myocardial infarction in single-beat ECG using Dual-Q TQWT and wavelet packet tensor decomposition' [Computer Methods and Programs in Biomedicine 184 (2020) 105120].

Comput Methods Programs Biomed 2021 Jan 10;198:105785. Epub 2020 Oct 10.

School of Biomedical Engineering, Faculty of Electronic Information and Electrical Engineering, Dalian University of Technology, Dalian, China; Faculty of Information Technology, University of Jyvaskyla, Jyvaskyla, 40014, Finland. Electronic address:

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http://dx.doi.org/10.1016/j.cmpb.2020.105785DOI Listing
January 2021

Dissociable Effects of Reward on P300 and EEG Spectra Under Conditions of High vs. Low Vigilance During a Selective Visual Attention Task.

Front Hum Neurosci 2020 24;14:207. Epub 2020 Jun 24.

Centre for Interdisciplinary Brain Research, Department of Psychology, Faculty of Education and Psychology, University of Jyvaskyla, Jyvaskyla, Finland.

The influence of motivation on selective visual attention in states of high vs. low vigilance is poorly understood. To explore the possible differences in the influence of motivation on behavioral performance and neural activity in high and low vigilance levels, we conducted a prolonged 2 h 20 min flanker task and provided monetary rewards during the 20- to 40- and 100- to 120-min intervals of task performance. Both the behavioral and electrophysiological measures were modulated by prolonged task engagement. Moreover, the effect of reward was different in high vs. low vigilance states. The monetary reward increased accuracy and decreased the reaction time (RT) and number of omitted responses in the low but not in the high vigilance state. The fatigue-related decrease in P300 amplitude recovered to its level in the high vigilance state by manipulating motivation, whereas the fatigue-related increase in P300 latency was not modulated by reward. Additionally, the fatigue-related increase in event-related spectral power at 1-4 Hz was sensitive to vigilance decrement and reward. However, the spectral power at 4-8 Hz was only affected by the decrease in vigilance. These electrophysiological measures were not influenced by motivation in the state of high vigilance. Our results suggest that neural processing capacity, but not the timing of processing, is sensitive to motivation. These findings also imply that the fatigue-related impairments in behavioral performance and neural activity underlying selective visual attention only partly recover after manipulating motivation. Furthermore, our results provide evidence for the dissociable neural mechanisms underlying the fatigue-related decrease vs. reward-related increase in attentional resources.
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http://dx.doi.org/10.3389/fnhum.2020.00207DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7327118PMC
June 2020

Older Age Increases the Amplitude of Muscle Stretch-Induced Cortical Beta-Band Suppression But Does not Affect Rebound Strength.

Front Aging Neurosci 2020 19;12:117. Epub 2020 May 19.

NeuroMuscular Research Center, Faculty of Sport and Health Sciences, University of Jyväskylä, Jyväskylä, Finland.

Healthy aging is associated with deterioration of the sensorimotor system, which impairs balance and somatosensation. However, the exact age-related changes in the cortical processing of sensorimotor integration are unclear. This study investigated primary sensorimotor cortex (SM1) oscillations in the 15-30 Hz beta band at rest and following (involuntary) rapid stretches to the triceps surae muscles (i.e., proprioceptive stimulation) of young and older adults. A custom-built, magnetoencephalography (MEG)-compatible device was used to deliver rapid (190°·s) ankle rotations as subjects sat passively in a magnetically-shielded room while MEG recorded their cortical signals. Eleven young (age 25 ± 3 years) and 12 older (age 70 ± 3 years) adults matched for physical activity level demonstrated clear 15-30 Hz beta band suppression and rebound in response to the stretches. A sub-sample (10 young and nine older) were tested for dynamic balance control on a sliding platform. Older adults had greater cortical beta power pre-stretch (e.g., right leg: 4.0 ± 1.6 fT vs. 5.6 ± 1.7 fT, = 0.044) and, subsequently, greater normalized movement-related cortical beta suppression post-proprioceptive stimulation (e.g., right leg: -5.8 ± 1.3 vs. -7.6 ± 1.7, = 0.01) than young adults. Furthermore, poorer balance was associated with stronger cortical beta suppression following proprioceptive stimulation ( = -0.478, = 0.038, = 19). These results provide further support that cortical processing of proprioception is hindered in older adults, potentially (adversely) influencing sensorimotor integration. This was demonstrated by the impairment of prompt motor action control, i.e., regaining perturbed balance. Finally, SM1 cortex beta suppression to a proprioceptive stimulus seems to indicate poorer sensorimotor functioning in older adults.
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http://dx.doi.org/10.3389/fnagi.2020.00117DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7248310PMC
May 2020

Physical activity, aerobic fitness, and brain white matter: Their role for executive functions in adolescence.

Dev Cogn Neurosci 2020 04 4;42:100765. Epub 2020 Feb 4.

Department of Psychology, Centre for Interdisciplinary Brain Research, University of Jyväskylä, Jyväskylä, Finland.

Physical activity and exercise beneficially link to brain properties and cognitive functions in older adults, but the findings concerning adolescents remain tentative. During adolescence, the brain undergoes significant changes, which are especially pronounced in white matter. Studies provide contradictory evidence regarding the influence of physical activity or aerobic-exercise on executive functions in youth. Little is also known about the link between both fitness and physical activity with the brain's white matter during puberty. We investigated the connection between aerobic fitness and physical activity with the white matter in 59 adolescents. We further determined whether white matter interacts with the connection of fitness or physical activity with core executive functions. Our results show that only the level of aerobic fitness, but not of physical activity relates to white matter. Furthermore, the white matter of the corpus callosum and the right superior corona radiata moderates the links of aerobic fitness and physical activity with working memory. Our results suggest that aerobic fitness and physical activity have an unequal contribution to the white matter properties in adolescents. We propose that the differences in white matter properties could underlie the variations in the relationship between either physical activity or aerobic fitness with working memory.
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http://dx.doi.org/10.1016/j.dcn.2020.100765DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7013351PMC
April 2020

The role of motor system in action-related language comprehension in L1 and L2: An fMRI study.

Brain Lang 2020 02 29;201:104714. Epub 2019 Nov 29.

Department of Psychology, University of Jyväskylä, Jyväskylä 40014, Finland; Centre for Interdisciplinary Brain Research, University of Jyväskylä, Jyväskylä 40014, Finland. Electronic address:

The framework of embodied cognition has challenged the modular view of a language-cognition divide by suggesting that meaning-retrieval critically involves the sensory-motor system. Despite extensive research into the neural mechanisms underlying language-motor coupling, it remains unclear how the motor system might be differentially engaged by different levels of linguistic abstraction and language proficiency. To address this issue, we used fMRI to quantify neural activations in brain regions underlying motor and language processing in Chinese-English speakers' processing of literal, metaphorical, and abstract language in their L1 and L2. Results overall revealed a response in motor ROIs gradually attenuating in intensity from literal to abstract via metaphorical language in both L1 and L2. Furthermore, contrast analyses between L1 and L2 showed overall greater activations of motor ROIs in the L2. We conclude that motor involvement in language processing is graded rather than all-or-none and that the motor system has a dual-functional role.
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http://dx.doi.org/10.1016/j.bandl.2019.104714DOI Listing
February 2020

Context-dependent minimisation of prediction errors involves temporal-frontal activation.

Neuroimage 2020 02 12;207:116355. Epub 2019 Nov 12.

Jyväskylä Centre for Interdisciplinary Brain Research, Department of Psychology, University of Jyväskylä, 40014, Jyväskylä, Finland. Electronic address:

According to the predictive coding model of perception, the brain constantly generates predictions of the upcoming sensory inputs. Perception is realised through a hierarchical generative model which aims at minimising the discrepancy between predictions and the incoming sensory inputs (i.e., prediction errors). Notably, prediction errors are weighted depending on precision of prior information. However, it remains unclear whether and how the brain monitors prior precision when minimising prediction errors in different contexts. The current study used magnetoencephalography (MEG) to address this question. We presented participants with repetition of two non-predicted probes embedded in context of high and low precision, namely mispredicted and unpredicted probes. Non-parametric permutation statistics showed that the minimisation of precision-weighted prediction errors started to dissociate on early components of the auditory responses (including the P1m and N1m), indicating that the brain can differentiate between these scenarios at an early stage of the auditory processing stream. Permutation statistics conducted on the depth-weighted statistical parametric maps (dSPM) source solutions of the repetition difference waves between the two non-predicted probes further revealed a cluster extending from the frontal areas to the posterior temporal areas in the left hemisphere. Overall, the results suggested that context precision not only changes the weighting of prediction errors but also modulates the dynamics of how prediction errors are minimised upon the learning of statistical regularities (achieved by stimulus repetition), which likely involves differential activation at temporal-frontal regions.
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http://dx.doi.org/10.1016/j.neuroimage.2019.116355DOI Listing
February 2020

Automated detection and localization system of myocardial infarction in single-beat ECG using Dual-Q TQWT and wavelet packet tensor decomposition.

Comput Methods Programs Biomed 2020 Feb 5;184:105120. Epub 2019 Oct 5.

School of Biomedical Engineering, Faculty of Electronic Information and Electrical Engineering, Dalian University of Technology, Dalian, China; Faculty of Information Technology, University of Jyvaskyla, Jyvaskyla, 40014, Finland. Electronic address:

Background And Objective: It is challenging to conduct real-time identification of myocardial infarction (MI) due to artifact corruption and high dimensionality of multi-lead electrocardiogram (ECG). In the present study, we proposed an automated single-beat MI detection and localization system using dual-Q tunable Q-factor wavelet transformation (Dual-Q TQWT) denoising algorithm.

Methods: After denoising and segmentation of ECG, a fourth-order wavelet tensor (leads × subbands × samples × beats) was constructed based on the discrete wavelet packet transform (DWPT), to represent the features considering the information of inter-beat, intra-beat, inter-frequency, and inter-lead. To reduce the tensor dimension and preserve the intrinsic information, the multilinear principal component analysis (MPCA) was employed. Afterward, 84 discriminate features were fed into a classifier of bootstrap-aggregated decision trees (Treebagger). A total of 78 healthy and 328 MI (6 types) records including 57557 beats were chosen from PTB diagnostic ECG database for evaluation.

Results: The validation results demonstrated that our proposed MI detection and localization system embedded with Dual-Q TQWT and wavelet packet tensor decomposition outperformed commonly used discrete wavelet transform (DWT), empirical mode decomposition (EMD) denoising methods and vector-based PCA method. With the Treebagger classifier, we obtained an accuracy of 99.98% in beat level and an accuracy of 97.46% in record level training/testing for MI detection. We also achieved an accuracy of 99.87% in beat level and an accuracy of 90.39% in record level for MI localization.

Conclusion: Altogether, the automated system brings potential improvement in automated detection and localization of MI in clinical practice.
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http://dx.doi.org/10.1016/j.cmpb.2019.105120DOI Listing
February 2020

Predicting domain-specific actions in expert table tennis players activates the semantic brain network.

Neuroimage 2019 10 5;200:482-489. Epub 2019 Jul 5.

Department of Psychology, Shanghai University of Sport, Shanghai, 200438, China. Electronic address:

Motor expertise acquired during long-term training in sports enables top athletes to predict the outcomes of domain-specific actions better than nonexperts do. However, whether expert players encode actions, in addition to the concrete sensorimotor level, also at a more abstract, conceptual level, remains unclear. The present study manipulated the congruence between body kinematics and the subsequent ball trajectory in videos of an expert player performing table tennis serves. By using functional magnetic resonance imaging, the brain activity was evaluated in expert and nonexpert table tennis players during their predictions on the fate of the ball trajectory in congruent versus incongruent videos. Compared with novices, expert players showed greater activation in the sensorimotor areas (right precentral and postcentral gyri) in the comparison between incongruent vs. congruent videos. They also showed greater activation in areas related to semantic processing: the posterior inferior parietal lobe (angular gyrus), middle temporal gyrus, and ventromedial prefrontal cortex. These findings indicate that action anticipation in expert table tennis players engages both semantic and sensorimotor regions and suggests that skilled action observation in sports utilizes predictions both at motor-kinematic and conceptual levels.
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http://dx.doi.org/10.1016/j.neuroimage.2019.06.035DOI Listing
October 2019

Left hemisphere enhancement of auditory activation in language impaired children.

Sci Rep 2019 06 24;9(1):9087. Epub 2019 Jun 24.

Centre for Interdisciplinary Brain Research, Department of Psychology, University of Jyväskylä, P.O. Box 35, FI-40014, Jyväskylä, Finland.

Specific language impairment (SLI) is a developmental disorder linked to deficient auditory processing. In this magnetoencephalography (MEG) study we investigated a specific prolonged auditory response (N250m) that has been reported predominantly in children and is associated with level of language skills. We recorded auditory responses evoked by sine-wave tones presented alternately to the right and left ear of 9-10-year-old children with SLI (n = 10) and children with typical language development (n = 10). Source analysis was used to isolate the N250m response in the left and right hemisphere. In children with language impairment left-hemisphere N250m responses were enhanced compared to those of controls, while no group difference was found in the right hemisphere. Consequently, language impaired children lacked the typical right-ward asymmetry that was found in control children. Furthermore, left but not right hemisphere N250m responses correlated positively with performance on a phonological processing task in the SLI group exclusively, possibly signifying a compensatory mechanism for delayed maturation of language processing. These results suggest that enhanced left-hemisphere auditory activation reflects a core neurophysiological manifestation of developmental language disorders, and emphasize the relevance of this developmentally specific activation pattern for competent language development.
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http://dx.doi.org/10.1038/s41598-019-45597-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6591383PMC
June 2019

Dynamics of brain activation during learning of syllable-symbol paired associations.

Neuropsychologia 2019 06 28;129:93-103. Epub 2019 Mar 28.

Department of Neuroscience and Biomedical Engineering, 00076, Aalto University, Finland; Aalto NeuroImaging, 00076, Aalto University, Finland.

Initial stages of reading acquisition require the learning of letter and speech sound combinations. While the long-term effects of audio-visual learning are rather well studied, relatively little is known about the short-term learning effects at the brain level. Here we examined the cortical dynamics of short-term learning using magnetoencephalography (MEG) and electroencephalography (EEG) in two experiments that respectively addressed active and passive learning of the association between shown symbols and heard syllables. In experiment 1, learning was based on feedback provided after each trial. The learning of the audio-visual associations was contrasted with items for which the feedback was meaningless. In experiment 2, learning was based on statistical learning through passive exposure to audio-visual stimuli that were consistently presented with each other and contrasted with audio-visual stimuli that were randomly paired with each other. After 5-10 min of training and exposure, learning-related changes emerged in neural activation around 200 and 350 ms in the two experiments. The MEG results showed activity changes at 350 ms in caudal middle frontal cortex and posterior superior temporal sulcus, and at 500 ms in temporo-occipital cortex. Changes in brain activity coincided with a decrease in reaction times and an increase in accuracy scores. Changes in EEG activity were observed starting at the auditory P2 response followed by later changes after 300 ms. The results show that the short-term learning effects emerge rapidly (manifesting in later stages of audio-visual integration processes) and that these effects are modulated by selective attention processes.
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http://dx.doi.org/10.1016/j.neuropsychologia.2019.03.016DOI Listing
June 2019

Children show hemispheric differences in the basic auditory response properties.

Hum Brain Mapp 2019 06 18;40(9):2699-2710. Epub 2019 Feb 18.

Aalto NeuroImaging, Aalto University, Espoo, Finland.

Auditory cortex in each hemisphere shows preference to sounds from the opposite hemifield in the auditory space. Besides this contralateral dominance, the auditory cortex shows functional and structural lateralization, presumably influencing the features of subsequent auditory processing. Children have been shown to differ from adults in the hemispheric balance of activation in higher-order auditory based tasks. We studied, first, whether the contralateral dominance can be detected in 7- to 8-year-old children and, second, whether the response properties of auditory cortex in children differ between hemispheres. Magnetoencephalography (MEG) responses to simple tones revealed adult-like contralateral preference that was, however, extended in time in children. Moreover, we found stronger emphasis towards mature response properties in the right than left hemisphere, pointing to faster maturation of the right-hemisphere auditory cortex. The activation strength of the child-typical prolonged response was significantly decreased with age, within the narrow age-range of the studied child population. Our results demonstrate that although the spatial sensitivity to the opposite hemifield has emerged by 7 years of age, the population-level neurophysiological response shows salient immature features, manifested particularly in the left hemisphere. The observed functional differences between hemispheres may influence higher-level processing stages, for example, in language function.
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http://dx.doi.org/10.1002/hbm.24553DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6865417PMC
June 2019

Aging and Strength Training Influence Knee Extensor Intermuscular Coherence During Low- and High-Force Isometric Contractions.

Front Physiol 2018 23;9:1933. Epub 2019 Jan 23.

Department of Psychology, Centre for Interdisciplinary Brain Research, Faculty of Education and Psychology, University of Jyväskylä, Jyväskylä, Finland.

Aging is associated with reduced maximum force production and force steadiness during low-force tasks, but both can be improved by training. Intermuscular coherence measures coupling between two peripheral surface electromyography (EMG) signals in the frequency domain. It is thought to represent the presence of common input to alpha-motoneurons, but the functional meaning of intermuscular coherence, particularly regarding aging and training, remain unclear. This study investigated knee extensor intermuscular coherence in previously sedentary young (18-30 years) and older (67-73 years) subjects before and after a 14-week strength training intervention. YOUNG and OLDER groups performed maximum unilateral isometric knee extensions [100% maximum voluntary contraction (MVC)], as well as force steadiness tests at 20 and 70% MVC, pre- and post-training. Intermuscular (i.e., EMG-EMG) coherence analyses were performed for all (three) contraction intensities in vastus lateralis and medialis muscles. Pre-training coefficient of force variation (i.e., force steadiness) and MVC (i.e., maximum torque) were similar between groups. Both groups improved MVC through training, but YOUNG improved more than OLDER (42 ± 27 Nm versus 18 ± 16 Nm, = 0.022). Force steadiness did not change during 20% MVC trials in either group, but YOUNG demonstrated increased coefficient of force variation during 70% MVC trials (1.28 ± 0.46 to 1.57 ± 0.70, = 0.01). YOUNG demonstrated greater pre-training coherence during 20% and 70% MVC trials, particularly within the 8-14 Hz (e.g., 20%: 0.105 ± 0.119 versus 0.016 ± 0.009, = 0.001) and 16-30 Hz (20%: 0.063 ± 0.078 versus 0.012 ± 0.007, = 0.002) bands, but not during 100% MVC trials. Strength training led to increases in intermuscular coherence within the 40-60 Hz band during 70% MVC trials in YOUNG only, while OLDER decreased within the 8-14 Hz band during 100% MVC trials. Age-related differences in intermuscular coherence were observed between young and older individuals, even when neuromuscular performance levels were similar. The functional significance of intermuscular coherence remains unclear, since coherence within different frequency bands did not explain any of the variance in the regression models for maximum strength or force steadiness during 20 and 70% MVC trials.
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http://dx.doi.org/10.3389/fphys.2018.01933DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6351450PMC
January 2019

Aerobic fitness, but not physical activity, is associated with grey matter volume in adolescents.

Behav Brain Res 2019 04 9;362:122-130. Epub 2019 Jan 9.

Department of Psychology, Centre for Interdisciplinary Brain Research, University of Jyväskylä, Jyväskylä, Finland.

Higher levels of aerobic fitness and physical activity are linked to beneficial effects on brain health, especially in older adults. The generalizability of these earlier results to young individuals is not straightforward, because physiological responses (such as cardiovascular responses) to exercise may depend on age. Earlier studies have mostly focused on the effects of either physical activity or aerobic fitness on the brain. Yet, while physical activity indicates the amount of activity, aerobic fitness is an adaptive state or attribute that an individual has or achieves. Here, by measuring both physical activity and aerobic fitness in the same study, we aimed to differentiate the association between these two measures and grey matter volume specifically. Magnetic resonance imaging scans were used to study volumes of 30 regions of interest located in the frontal, motor and subcortical areas of 60 adolescents (12.7-16.2 years old). Moderate-to-vigorous intensity physical activity (MVPA) was measured with hip-worn accelerometers and aerobic fitness was assessed with a 20-m shuttle run. Multiple regression analyses revealed a negative association between aerobic fitness and left superior frontal cortex volume and a positive association between aerobic fitness and the left pallidum volume. No associations were found between MVPA and any brain region of interest. These results demonstrate unequal contribution of physical activity and aerobic fitness on grey matter volumes, with inherent or achieved capacity (aerobic fitness) showing clearer associations than physical activity.
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http://dx.doi.org/10.1016/j.bbr.2018.12.041DOI Listing
April 2019

Behavioral Inhibition Underlies the Link Between Interoceptive Sensitivity and Anxiety-Related Temperamental Traits.

Front Psychol 2018 21;9:1026. Epub 2018 Jun 21.

Department of Psychology, Centre for Interdisciplinary Brain Research, University of Jyväskylä, Jyväskylä, Finland.

Interoceptive sensitivity (IS) is a biologically determined, constitutional trait of an individual. High IS has been often associated with proneness to anxiety. This association has been explained by elevated autonomic responsiveness in anxious individuals. However, in a heartbeat discrimination task (discrimination of heartbeats' simultaneity to an external stimulus) low cardiac responsiveness has accompanied enhanced performance. The relation between these factors seems task dependent, and cannot comprehensively explain the link between IS and anxiety. We explored for additional explanatory factors for this link. More specifically, we studied which anxiety-related temperamental traits most strongly predict IS in the discrimination task. Compatibly with earlier findings, IS was positively associated with individual trait anxiety and also other related traits such as negative affect, emotional intensity, and introversion. Interestingly, behavioral inhibition was the temperamental trait that most strongly predicted high IS, and, in fact, accounted for its significant associations with the other anxiety-related temperamental traits. Good performance on heartbeat discrimination task may reflect adaptive attentional control abilities in behaviorally inhibited individuals. These results can improve our understanding of how IS and other traits together determine the personality and wellbeing of a human individual.
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http://dx.doi.org/10.3389/fpsyg.2018.01026DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6021514PMC
June 2018

Cortical Proprioceptive Processing Is Altered by Aging.

Front Aging Neurosci 2018 14;10:147. Epub 2018 Jun 14.

Biology of Physical Activity and Neuromuscular Research Center, Faculty of Sport and Health Sciences, University of Jyväskylä, Jyväskylä, Finland.

Proprioceptive perception is impaired with aging, but little is known about aging-related deterioration of proprioception at the cortical level. Corticokinematic coherence (CKC) between limb kinematic and magnetoencephalographic (MEG) signals reflects cortical processing of proprioceptive afference. We, thus, compared CKC strength to ankle movements between younger and older subjects, and examined whether CKC predicts postural stability. Fifteen younger (range 18-31 years) and eight older (66-73 years) sedentary volunteers were seated in MEG, while their right and left ankle joints were moved separately at 2 Hz (for 4 min each) using a novel MEG-compatible ankle-movement actuator. Coherence was computed between foot acceleration and MEG signals. CKC strength at the movement frequency (F0) and its first harmonic (F1) was quantified. In addition, postural sway was quantified during standing eyes-open and eyes-closed tasks to estimate motor performance. CKC peaked in the gradiometers over the vertex, and was significantly stronger (~76%) at F0 for the older than younger subjects. At F1, only the dominant-leg CKC was significantly stronger (~15%) for the older than younger subjects. In addition, CKC (at F1) was significantly stronger in the non-dominant than dominant leg, but only in the younger subjects. Postural sway was significantly (~64%) higher in the older than younger subjects when standing with eyes closed. Regression models indicated that CKC strength at F1 in the dominant leg and age were the only significant predictors for postural sway. Our results indicated that aging-related cortical-proprioceptive processing is altered by aging. Stronger CKC may reflect poorer cortical proprioceptive processing, and not solely the amount of proprioceptive afference as suggested earlier. In combination with ankle-movement actuator, CKC can be efficiently used to unravel proprioception-related-neuronal mechanisms and the related plastic changes in aging, rehabilitation, motor-skill acquisition, motor disorders etc.
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http://dx.doi.org/10.3389/fnagi.2018.00147DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6010536PMC
June 2018

Network Entropy for the Sequence Analysis of Functional Connectivity Graphs of the Brain.

Entropy (Basel) 2018 Apr 25;20(5). Epub 2018 Apr 25.

Faculty of Information Technology, University of Jyvaskyla, Jyvaskyla FIN-40014, Finland.

Dynamic representation of functional brain networks involved in the sequence analysis of functional connectivity graphs of the brain (FCGB) gains advances in uncovering evolved interaction mechanisms. However, most of the networks, even the event-related ones, are highly heterogeneous due to spurious interactions, which bring challenges to revealing the change patterns of interactive information in the complex dynamic process. In this paper, we propose a network entropy (NE) method to measure connectivity uncertainty of FCGB sequences to alleviate the spurious interaction problem in dynamic network analysis to realize associations with different events during a complex cognitive task. The proposed dynamic analysis approach calculated the adjacency matrices from ongoing electroencephalpgram (EEG) in a sliding time-window to form the FCGB sequences. The probability distribution of Shannon entropy was replaced by the connection sequence distribution to measure the uncertainty of FCGB constituting NE. Without averaging, we used time frequency transform of the NE of FCGB sequences to analyze the event-related changes in oscillatory activity in the single-trial traces during the complex cognitive process of driving. Finally, the results of a verification experiment showed that the NE of the FCGB sequences has a certain time-locked performance for different events related to driver fatigue in a prolonged driving task. The time errors between the extracted time of high-power NE and the recorded time of event occurrence were distributed within the range [-30 s, 30 s] and 90.1% of the time errors were distributed within the range [-10 s, 10 s]. The high correlation ( = 0.99997, < 0.001) between the timing characteristics of the two types of signals indicates that the NE can reflect the actual dynamic interaction states of brain. Thus, the method may have potential implications for cognitive studies and for the detection of physiological states.
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http://dx.doi.org/10.3390/e20050311DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7512830PMC
April 2018

Children show right-lateralized effects of spoken word-form learning.

PLoS One 2017 3;12(2):e0171034. Epub 2017 Feb 3.

Department of Neuroscience and Biomedical Engineering, and Aalto NeuroImaging, Aalto University, Espoo, Finland.

It is commonly thought that phonological learning is different in young children compared to adults, possibly due to the speech processing system not yet having reached full native-language specialization. However, the neurocognitive mechanisms of phonological learning in children are poorly understood. We employed magnetoencephalography (MEG) to track cortical correlates of incidental learning of meaningless word forms over two days as 6-8-year-olds overtly repeated them. Native (Finnish) pseudowords were compared with words of foreign sound structure (Korean) to investigate whether the cortical learning effects would be more dependent on previous proficiency in the language rather than maturational factors. Half of the items were encountered four times on the first day and once more on the following day. Incidental learning of these recurring word forms manifested as improved repetition accuracy and a correlated reduction of activation in the right superior temporal cortex, similarly for both languages and on both experimental days, and in contrast to a salient left-hemisphere emphasis previously reported in adults. We propose that children, when learning new word forms in either native or foreign language, are not yet constrained by left-hemispheric segmental processing and established sublexical native-language representations. Instead, they may rely more on supra-segmental contours and prosody.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0171034PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5291445PMC
August 2017

Gaze position reveals impaired attentional shift during visual word recognition in dysfluent readers.

PLoS One 2014 30;9(9):e108937. Epub 2014 Sep 30.

Centre for Interdisciplinary Brain Research, Department of Psychology, University of Jyväskylä, Jyväskylä, Finland.

Effects reflecting serial within-word processing are frequently found in pseudo- and non-word recognition tasks not only among fluent, but especially among dyslexic readers. However, the time course and locus of these serial within-word processing effects in the cognitive hierarchy (i.e., orthographic, phonological, lexical) have remained elusive. We studied whether a subject's eye movements during a lexical decision task would provide information about the temporal dynamics of serial within-word processing. We assumed that if there is serial within-word processing proceeding from left to right, items with informative beginnings would attract the gaze position and (micro-)saccadic eye movements earlier in time relative to those with informative endings. In addition, we compared responses to word, non-word, and pseudo-word items to study whether serial within-word processing stems mainly from a lexical, orthographic, or phonological processing level, respectively. Gaze positions showed earlier responses to anomalies located at pseudo- and non-word beginnings rather than endings, whereas informative word beginnings or endings did not affect gaze positions. The overall pattern of results suggests parallel letter processing of real words and rapid serial within-word processing when reading novel words. Dysfluent readers' gaze position responses toward anomalies located at pseudo- and non-word endings were delayed substantially, suggesting impairment in serial processing at an orthographic processing level.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0108937PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4182581PMC
June 2015

Abnormal functioning of the left temporal lobe in language-impaired children.

Brain Lang 2014 Mar 22;130:11-8. Epub 2014 Feb 22.

Network of Academic Health Centres, Departments of General Practice and Primary Healthcare, HUS Institute of Clinical Medicine, Helsinki, Finland.

Specific language impairment is associated with enduring problems in language-related functions. We followed the spatiotemporal course of cortical activation in SLI using magnetoencephalography. In the experiment, children with normal and impaired language development heard spoken real words and pseudowords presented only once or two times in a row. In typically developing children, the activation in the bilateral superior temporal cortices was attenuated to the second presentation of the same word. In SLI children, this repetition effect was nearly nonexistent in the left hemisphere. Furthermore, the activation was equally strong to words and pseudowords in SLI children whereas in the typically developing children the left hemisphere activation persisted longer for pseudowords than words. Our results indicate that the short-term maintenance of linguistic activation that underlies spoken word recognition is defective in SLI particularly in the left language-dominant hemisphere. The unusually rapid decay of speech-evoked activation can contribute to impaired vocabulary growth.
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http://dx.doi.org/10.1016/j.bandl.2014.01.005DOI Listing
March 2014

Corticomuscular coherence is tuned to the spontaneous rhythmicity of speech at 2-3 Hz.

J Neurosci 2012 Mar;32(11):3786-90

Brain Research Unit, O.V. Lounasmaa Laboratory, Aalto University, FI-00076 Aalto, Finland.

Human speech features rhythmicity that frames distinctive, fine-grained speech patterns. Speech can thus be counted among rhythmic motor behaviors that generally manifest characteristic spontaneous rates. However, the critical neural evidence for tuning of articulatory control to a spontaneous rate of speech has not been uncovered. The present study examined the spontaneous rhythmicity in speech production and its relationship to cortex-muscle neurocommunication, which is essential for speech control. Our MEG results show that, during articulation, coherent oscillatory coupling between the mouth sensorimotor cortex and the mouth muscles is strongest at the frequency of spontaneous rhythmicity of speech at 2-3 Hz, which is also the typical rate of word production. Corticomuscular coherence, a measure of efficient cortex-muscle neurocommunication, thus reveals behaviorally relevant oscillatory tuning for spoken language.
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http://dx.doi.org/10.1523/JNEUROSCI.3191-11.2012DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6703459PMC
March 2012

Parametric merging of MEG and fMRI reveals spatiotemporal differences in cortical processing of spoken words and environmental sounds in background noise.

Cereb Cortex 2012 Jan 25;22(1):132-43. Epub 2011 May 25.

Department of Cognitive Neuroscience, Faculty of Psychology and Neuroscience, Maastricht University, 6200 MD Maastricht, the Netherlands.

There is an increasing interest to integrate electrophysiological and hemodynamic measures for characterizing spatial and temporal aspects of cortical processing. However, an informative combination of responses that have markedly different sensitivities to the underlying neural activity is not straightforward, especially in complex cognitive tasks. Here, we used parametric stimulus manipulation in magnetoencephalography (MEG) and functional magnetic resonance imaging (fMRI) recordings on the same subjects, to study effects of noise on processing of spoken words and environmental sounds. The added noise influenced MEG response strengths in the bilateral supratemporal auditory cortex, at different times for the different stimulus types. Specifically for spoken words, the effect of noise on the electrophysiological response was remarkably nonlinear. Therefore, we used the single-subject MEG responses to construct parametrization for fMRI data analysis and obtained notably higher sensitivity than with conventional stimulus-based parametrization. fMRI results showed that partly different temporal areas were involved in noise-sensitive processing of words and environmental sounds. These results indicate that cortical processing of sounds in background noise is stimulus specific in both timing and location and provide a new functionally meaningful platform for combining information obtained with electrophysiological and hemodynamic measures of brain function.
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http://dx.doi.org/10.1093/cercor/bhr095DOI Listing
January 2012

Speech perception in the child brain: cortical timing and its relevance to literacy acquisition.

Hum Brain Mapp 2011 Dec 9;32(12):2193-206. Epub 2011 Mar 9.

Brain Research Unit, Low Temperature Laboratory, Aalto University School of Science and Technology, Espoo, Finland.

Speech processing skills go through intensive development during mid-childhood, providing basis also for literacy acquisition. The sequence of auditory cortical processing of speech has been characterized in adults, but very little is known about the neural representation of speech sound perception in the developing brain. We used whole-head magnetoencephalography (MEG) to record neural responses to speech and nonspeech sounds in first-graders (7-8-year-old) and compared the activation sequence to that in adults. In children, the general location of neural activity in the superior temporal cortex was similar to that in adults, but in the time domain the sequence of activation was strikingly different. Cortical differentiation between sound types emerged in a prolonged response pattern at about 250 ms after sound onset, in both hemispheres, clearly later than the corresponding effect at about 100 ms in adults that was detected specifically in the left hemisphere. Better reading skills were linked with shorter-lasting neural activation, speaking for interdependence of the maturing neural processes of auditory perception and developing linguistic skills. This study uniquely utilized the potential of MEG in comparing both spatial and temporal characteristics of neural activation between adults and children. Besides depicting the group-typical features in cortical auditory processing, the results revealed marked interindividual variability in children.
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http://dx.doi.org/10.1002/hbm.21181DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6870499PMC
December 2011

Uric acid and cognition in Parkinson's disease: a follow-up study.

Parkinsonism Relat Disord 2011 Jun 12;17(5):333-7. Epub 2011 Feb 12.

Meilahti Hospital of Helsinki University Central Hospital, Haartmaninkatu 4, 00029 HUS, Finland.

Cognitive changes are common in Parkinson's disease (PD). Low plasma uric acid (UA) level is associated with risk of PD and predicts faster progression of motor symptoms in established disease. Whether UA levels predict cognitive changes has not been studied. In a crossectional study, our group has previously shown an association of plasma and urine UA levels with cognition in PD. The aim of the present controlled longitudinal study was to examine the evolution of cognitive changes and the prognostic value of the UA levels on cognition in the previously reported PD-patient cohort. Of the original 40 patients, 31 were available for follow-up after three years. Both plasma and daily urine UA levels were measured, nutrition was evaluated using 4-day dietary recall diary and cognition was assessed by a thorough neuropsychological examination including computerized tasks with Cognispeed©. The plasma and urine UA levels of the patients remained stable during the follow-up. At the same time, the rate of cognitive decline was unexpectedly slow. A statistically significant deterioration was noted in verbal fluency (p=0.04) and in Cognispeed©'s vigilance task (p=0.0001). In forward linear regression analysis only the baseline daily urine UA level contributed to verbal fluency (p=0.01), picture completion (p=0.001), block design (p=0.006), vigilance (p=0.006), subtraction (p=0.01) and statement verification (p=0.04) tasks. The implications of the study results are discussed.
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http://dx.doi.org/10.1016/j.parkreldis.2011.01.013DOI Listing
June 2011

Spatiotemporal convergence of semantic processing in reading and speech perception.

J Neurosci 2009 Jul;29(29):9271-80

Brain Research Unit, Low Temperature Laboratory, Helsinki University of Technology, 02015 TKK, Espoo, Finland.

Retrieval of word meaning from the semantic system and its integration with context are often assumed to be shared by spoken and written words. How is modality-independent semantic processing manifested in the brain, spatially and temporally? Time-sensitive neuroimaging allows tracking of neural activation sequences. Use of semantically related versus unrelated word pairs or sentences ending with a semantically highly or less plausible word, in separate studies of the auditory and visual modality, has associated lexical-semantic analysis with sustained activation at approximately 200-800 ms. Magnetoencephalography (MEG) studies have further identified the superior temporal cortex as a main locus of the semantic effect. Nevertheless, a direct comparison of the spatiotemporal neural correlates of visual and auditory word comprehension in the same brain is lacking. We used MEG to compare lexical-semantic analysis in the visual and auditory domain in the same individuals, and contrasted it with phonological analysis that, according to models of language perception, should occur at a different time with respect to semantic analysis in reading and speech perception. The stimuli were lists of four words that were either semantically or phonologically related, or with the final word unrelated to the preceding context. Superior temporal activation reflecting semantic processing occurred similarly in the two modalities, left-lateralized at 300-450 ms and thereafter bilaterally, generated in close-by areas. Effect of phonology preceded the semantic effect in speech perception but not in reading. The present data indicate involvement of the middle superior temporal cortex in semantic processing from approximately 300 ms onwards, regardless of input modality.
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http://dx.doi.org/10.1523/JNEUROSCI.5860-08.2009DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6665572PMC
July 2009

Neural processing of spoken words in specific language impairment and dyslexia.

Brain 2009 Jul 4;132(Pt 7):1918-27. Epub 2009 Jun 4.

Brain Research Unit, Low Temperature Laboratory, Helsinki University of Technology, Espoo, Finland.

Young adults with a history of specific language impairment (SLI) differ from reading-impaired (dyslexic) individuals in terms of limited vocabulary and poor verbal short-term memory. Phonological short-term memory has been shown to play a significant role in learning new words. We investigated the neural signatures of auditory word recognition and word repetition in young adults with SLI, dyslexia and normal language development using magnetoencephalography. The stimuli were 7-8 letter spoken real words and pseudo-words. They evoked a transient peak at 100 ms (N100m) followed by longer-lasting activation peaking around 400 ms (N400m) in the left and right superior temporal cortex. Both word repetition (first vs. immediately following second presentation) and lexicality (words vs. pseudowords) modulated the N400m response. An effect of lexicality was detected about 400 ms onwards as activation culminated for words but continued for pseudo-words. This effect was more pronounced in the left than right hemisphere in the control subjects. The left hemisphere lexicality effect was also present in the dyslexic adults, but it was non-significant in the subjects with SLI, possibly reflecting their limited vocabulary. The N400m activation between 200 and 700 ms was attenuated by the immediate repetition of words and pseudo-words in both hemispheres. In SLI adults the repetition effect evaluated at 200-400 ms was abnormally weak. This finding suggests impaired short-term maintenance of linguistic activation that underlies word recognition. Furthermore, the size of the repetition effect decreased from control subjects through dyslexics to SLIs, i.e. when advancing from milder to more severe language impairment. The unusually rapid decay of speech-evoked activation could have a detrimental role on vocabulary growth in children with SLI.
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http://dx.doi.org/10.1093/brain/awp134DOI Listing
July 2009