Browsing by Author "Autti, Taina"

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    Auditory and Cognitive Deficits Associated with Acquired Amusia after Stroke: A Magnetoencephalography and Neuropsychological Follow-Up Study
    (2010) Särkämö, Teppo; Tervaniemi, Mari; Soinila, Seppo; Autti, Taina; Silvennoinen, Heli M.; Laine, Matti; Hietanen, Marja; Pihko, Elina; Department of Neuroscience and Biomedical Engineering
    Acquired amusia is a common disorder after damage to the middle cerebral artery (MCA) territory. However, its neurocognitive mechanisms, especially the relative contribution of perceptual and cognitive factors, are still unclear. We studied cognitive and auditory processing in the amusic brain by performing neuropsychological testing as well as magnetoencephalography (MEG) measurements of frequency and duration discrimination using magnetic mismatch negativity (MMNm) recordings. Fifty-three patients with a left (n = 24) or right (n = 29) hemisphere MCA stroke (MRI verified) were investigated 1 week, 3 months, and 6 months after the stroke. Amusia was evaluated using the Montreal Battery of Evaluation of Amusia (MBEA). We found that amusia caused by right hemisphere damage (RHD), especially to temporal and frontal areas, was more severe than amusia caused by left hemisphere damage (LHD). Furthermore, the severity of amusia was found to correlate with weaker frequency MMNm responses only in amusic RHD patients.Additionally, within the RHD subgroup, the amusic patients who had damage to the auditory cortex (AC) showed worse recovery on the MBEA as well as weaker MMNm responses throughout the 6-month follow-up than the non-amusic patients or the amusic patients without AC damage. Furthermore, the amusic patients both with and without AC damage performed worse than the non-amusic patients on tests of working memory, attention, and cognitive flexibility. These findings suggest domain-general cognitive deficits to be the primary mechanism underlying amusia without AC damage whereas amusia with AC damage is associated with both auditory and cognitive deficits.
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    Detection of Aspartylglucosaminuria Patients from Magnetic Resonance Images by a Machine-Learning-Based Approach
    (MDPI AG, 2022-11) Ruohola, Arttu; Salli, Eero; Roine, Timo; Tokola, Anna; Laine, Minna; Tikkanen, Ritva; Savolainen, Sauli; Autti, Taina; University of Helsinki; Department of Neuroscience and Biomedical Engineering; Justus Liebig University Giessen
    Magnetic resonance (MR) imaging data can be used to develop computer-assisted diagnostic tools for neurodegenerative diseases such as aspartylglucosaminuria (AGU) and other lysosomal storage disorders. MR images contain features that are suitable for the classification and differentiation of affected individuals from healthy persons. Here, comparisons were made between MRI features extracted from different types of magnetic resonance images. Random forest classifiers were trained to classify AGU patients (n = 22) and healthy controls (n = 24) using volumetric features extracted from T1-weighted MR images, the zone variance of gray level size zone matrix (GLSZM) calculated from magnitude susceptibility-weighted MR images, and the caudate–thalamus intensity ratio computed from T2-weighted MR images. The leave-one-out cross-validation and area under the receiver operating characteristic curve were used to compare different models. The left–right-averaged, normalized volumes of the 25 nuclei of the thalamus and the zone variance of the thalamus demonstrated equal and excellent performance as classifier features for binary organization between AGU patients and healthy controls. Our findings show that texture-based features of susceptibility-weighted images and thalamic volumes can differentiate AGU patients from healthy controls with a very low error rate.
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    Topological alterations of the structural brain connectivity network in children with juvenile neuronal ceroid lipofuscinosis
    (American Society of Neuroradiology, 2019) Roine, Timo; Roine, Ulrika; Tokola, Anna; Balk, Marja; Mannerkoski, Minna; Åberg, Laura E.; Tuula, Lönnqvist; Autti, Taina; Department of Neuroscience and Biomedical Engineering; Helsinki University Central Hospital; HUS Medical Imaging Center; University of Helsinki
    Background and Purpose: We used diffusion MRI to investigate the structural brain connectivity networks in juvenile neuronal ceroid lipofuscinosis, a neurodegenerative lysosomal storage disease of the childhood. Although changes in conventional MRI are typically not visually apparent under the age of ten, we previously found significant microstructural abnormalities by using diffusion MRI. Therefore, we hypothesized that the structural connectivity networks would also be affected in the disease. Materials and Methods: We acquired diffusion MRI data from 14 children with juvenile neuronal ceroid lipofuscinosis (mean age 9.6±3.4 years; 10 boys) and 14 control subjects (mean age 11.2±2.3 years; 7 boys). A follow-up MRI was performed for 12 of the patients (mean age 11.4±3.2, 8 boys). We used graph theoretical analysis to investigate the global and local properties of the structural brain connectivity networks reconstructed with constrained spherical deconvolution based whole-brain probabilistic tractography. Results: We found significantly increased characteristic path length (P=0.003) and decreased degree (P=0.003) suggesting decreased network integration and centrality in children with juvenile neuronal ceroid lipofuscinosis. The findings were similar for the follow-up MRI, and there were no significant differences between the two acquisitions of the patients. In addition, we found that the disease severity correlated negatively (P<0.05/7) with integration, segregation, centrality, and small-worldness of the networks. Moreover, we found significantly (P<0.05/164) decreased local efficiency in the left supramarginal gyrus and temporal plane and decreased strength in the right lingual gyrus. Conclusion: We found significant global and local network alterations in juvenile neuronal ceroid lipofuscinosis correlating with the disease severity, and in areas related to the symptomatology.
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    Topological Structural Brain Connectivity Alterations in Aspartylglucosaminuria: A Case-Control Study
    (American Society of Neuroradiology, 2023-01) Roine, Ulrika; Tokola, A.M.; Autti, Taina; Roine, Timo; University of Helsinki; Department of Neuroscience and Biomedical Engineering
    BACKGROUND AND PURPOSE: We investigated global and local properties of the structural brain connectivity networks in aspartylglucosaminuria, an autosomal recessive and progressive neurodegenerative lysosomal storage disease. Brain connectivity in aspartylglucosaminuria has not been investigated before, but previous structural MR imaging studies have shown brain atrophy, delayed myelination, and decreased thalamic and increased periventricular WM T2 signal intensity. MATERIALS AND METHODS: We acquired diffusion MR imaging and T1-weighted data from 12 patients with aspartylglucosaminuria (mean age, 23 [SD, 8] years; 5 men), and 30 healthy controls (mean age, 25 [SD, 10] years; 13 men). We performed whole-brain constrained spherical deconvolution tractography, which enables the reconstruction of neural tracts through regions with complex fiber configurations, and used graph-theoretical analysis to investigate the structural brain connectivity networks. RESULTS: The integration of the networks was decreased, as demonstrated by a decreased normalized global efficiency and an increased normalized characteristic path length. In addition, the average strength of the networks was decreased. In the local analyses, we found decreased strength in 11 nodes, including, for example, the right thalamus, right putamen, and, bilaterally, several occipital and temporal regions. CONCLUSIONS: We found global and local structural connectivity alterations in aspartylglucosaminuria. Biomarkers related to the treatment efficacy are needed, and brain network properties may provide the means for long term follow-up.