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Introduction: Chronic subjective tinnitus is associated with cognitive disruptions affecting perception, thinking, language, reasoning, problem solving, memory, visual tasks (reading) and attention. Objective: To evaluate existence of any association between tinnitus parameters and neuropsychological performance to explain cognitive processing. Materials and Methods: Study design was prospective, consisting 25 patients with idiopathic chronic subjective tinnitus and gave informed consent before planning their treatment. Neuropsychological profile included (i) performance on verbal information, comprehension, arithmetic and digit span; (ii) non-verbal performance for visual pattern completion analogies; (iii) memory performance for long-term, recent, delayed-recall, immediate-recall, verbal-retention, visualretention, visual recognition; (iv) reception, interpretation and execution for visual motor gestalt. Correlation between tinnitus onset duration/ loudness perception with neuropsychological profile was assessed by calculating Spearman's coefficient. Results: Findings suggest that tinnitus may interfere with cognitive processing especially performance on digit span, verbal comprehension, mental balance, attention & concentration, immediate recall, visual recognition and visual-motor gestalt subtests. Negative correlation between neurocognitive tasks with tinnitus loudness and onset duration indicated their association. Positive correlation between tinnitus and visual-motor gestalt performance indicated the brain dysfunction. Conclusion: Tinnitus association with non-auditory processing of verbal, visual and visuo-spatial information suggested neuroplastic changes that need to be targeted in cognitive rehabilitation.

Introduction: Parkinson's disease (PD) is a neurological disorder, which is diagnosed on the basis of clinical history and examination alone as there are no diagnostic tests available. However, the current diagnosis highly depends on the knowledge and experience of clinicians and hence subjective in nature. Thus, the focus of this study is to develop a computer-aided diagnosis (CAD) method using T1-weighted magnetic resonance imaging (MRI) to differentiate PD from controls. Method: The proposed method utilizes graph-theory-based spectral feature selection method to select a set of discriminating features from whole brain volume. A decision model is built using support vector machine as a classifier with leave-one-out cross-validation scheme. The performance measures, namely, sensitivity, specificity, and classification accuracy, are utilized to evaluate the performance of the decision model. The efficacy of the proposed method is checked on volumetric 3D T1-weighted (1 mm iso-voxel) MRI dataset of 30 PD patients and 30 age and gender matched controls acquired with 1.5T MRI scanner. Results: Experimental results demonstrate that the proposed method is able to differentiate PD from controls with an accuracy of 86.67%, which encourages the use of CAD. The performance of the proposed method outperforms the existing methods except one. In addition, it is observed that the maximum number of selected features belong to caudate region followed by cuneus region. Thus, these regions may be considered as potential biomarkers in diagnosis of PD. Conclusion: The proposed method may be utilized by the clinicians for diagnosis of PD.

Evaluation of brain cluster activation using the functional magnetic resonance imaging (fMRI) and diffusion tensor imaging (DTI) was sought in strabismic amblyopes. In this hospital-based case-control cross-sectional study, fMRI and DTI were conducted in strabismic amblyopes before initiation of any therapy and after visual recovery following the administration of occlusion therapy. FMRI was performed in 10 strabismic amblyopic subjects (baseline group) and in 5 left strabismic amblyopic children post-occlusion therapy after two-line visual improvement. Ten age-matched healthy children with right ocular dominance formed control group. Structural and functional MRI was carried out on 1.5T MR scanner. The visual task consisted of 8 Hz flickering checkerboard with red dot and occasional green dot. Blood-oxygen-level-dependent (BOLD) fMRI was analyzed using statistical parametric mapping and DTI on NordicIce (NordicNeuroLab) softwares. Reduced occipital activation was elicited when viewing with the amblyopic eye in amblyopes. An 'ipsilateral to viewing eye' pattern of calcarine BOLD activation was observed in controls and left amblyopes. Activation of cortical areas associated with visual processing differed in relation to the viewing eye. Following visual recovery on occlusion therapy, enhanced activity in bilateral hemispheres in striate as well as extrastriate regions when viewing with either eye was seen. Improvement in visual acuity following occlusion therapy correlates with hemodynamic activity in amblyopes.

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Purpose. Subjective tinnitus has different forms and degrees of severity. Many studies in the literature have assessed psychoacoustic characteristics of tinnitus but hardly any of them had focused on the association of audiological profile with onset duration and loudness perception. The aim of this study was to evaluate existence of any association between tinnitus loudness/onset duration and audiological profile to explain differences in prognosis. Method. Study design was prospective. The sample consisted of 26 subjects having tinnitus, which was divided into tinnitus and nontinnitus ears. Audiological profile included pure-tone audiometry, speech audiometry, tympanometry, acoustic reflex test, and auditory evoked potentials (early and middle latency). Unpaired t-test was applied to compare two subgroups. Correlation and association between tinnitus onset duration/loudness perception and audiological profile were also assessed by calculating Spearman's coefficient and Fischer exact value. Results. The two subgroups had significant differences for pure-tone and speech audiometry hearing thresholds. A significant association was observed between the high frequency/extended high frequency and tinnitus loudness/onset duration. Conclusion. The changes in hearing thresholds and auditory pathway are associated with an increase in tinnitus loudness and its onset duration. This knowledge would be helpful to differentiate between severity and chronicity of the patients for planning therapeutic management and predicting prognosis.

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Background: Swallowing is complex phenomena comprising oral (preparatory and pre-swallow positioning), oropharyngeal, pharyngeal and esophageal phases. The timing of these phases is controlled by brain stem pattern generators including reflex for oropharyngeal propulsion and transit. Dysphagia in Parkinson's disease (PD) commonly observed at late stages with aspiration, pneumonia and hospitalization. Objective: Can subtle oromotor signs (if any) be observed for planning early interventions in PD Methods: The present study investigated oromotor function in fourteen early PD (onset ≤2years; H&Y ≤2.5) with dynamic MRI using saline (water) bolus and compared with seven age-matched healthy controls. Results: All the patients with PD were non-symptomatic for dysphagia by self-reporting, and on clinical assessment (Part-II MDS-UPDRS, Swallowing disturbance questionnaire, SDQ and Clinical assessment of dysphagia in neurodegeneration, CADN). Qualitatively MR images visualized, differences in PD compared to healthy controls for tongue-wave, velar-closure or release, bolus placement, oropharyngeal reflex-initiation, transit-time, epiglottic-closure-coordination and post-swallow oral or pharyngeal residue. Descriptive analysis showed higher variability of velar-closure, oropharyngeal- and pharygoesophageal-transit time in patient with PD. Group analysis (two-sample) show significant difference for velar-closure. Conclusion: Multiple lingual-waves, reverse-tongue thrust, with delayed velar control attributed to incoordinated muscular rhythm. Variable oropharyngeal transit time (0.64 to 2.25 msec) in PD ascribed to brainstem degenerative changes. Findings imply that subtle observable early oromotor signs as pre-clinical manifestation when evaluated with non-invasive, non-contrast dynamic MRI support early intervention, to prevent late-stage aspiration episodes and consequent hospitalizations.