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Reading Acquisition and Phonological Awareness: Beyond the Segmental Level

Problem statement: Phonological awareness is a major contributor to reading development. While the literature has primarily focused on the segmental aspect of phonology, suprasegmental information, namely prosody, has been largely underexplored in comparison. Approach: This review focuses on recent behavioral and neuroimaging studies on the development of prosody sensitivity during early childhood and the influence of prosody on reading processes. Results: Overall, the literature highlights the importance of prosodic information, not only during reading acquisition in children, but also during silent reading in skilled readers. This contribution is independent of segmental phonology, but may influence the development of phonological awareness. Conclusion: The current findings open the door to the development of new reading assessment tools that can allow determining whether pre-literacy students are at risk for reading development difficulties.

Diphenylhydantoin Promotes Proliferation in The Subventricular Zone and Dentate Gyrus

Problem statement: Diphenylhydantoin (phenytoin) is an antiepileptic drug that generates hyperplasia in some tissue by stimulating Epidermal Growth Factor (EGFR) and Platelet-Derived Growth Factor beta (PDGFR-β) receptors and by increasing serum levels of basic fibroblast growth factor (bFGF, FGF2 or FGF-β). Neural stem cells in the adult brain have been isolated from three regions: the Subventricular Zone (SVZ) lining the lateral wall of the lateral ventricles, the Subgranular Zone (SGZ) in the dentate gyrus at the hippocampus and the Subgranular Zone (SZC) lining between the hippocampus and the corpus callosum. Neural stem cells actively respond to bFGF, PDGFR-β or EGF by increasing their proliferation, survival and differentiation. The aim of this study was to evaluate the effect of phenytoin on proliferation and apoptosis in the three neurogenic niches in the adult brain. Approach: We orally administrated phenytoin with an oropharyngeal cannula for 30 days: 0 mg kg^-1 (controls), 1, 5, 10, 50 and 100 mg kg^-1. To label proliferative cells, three injections of 100 mg kg^-1 of BrdU was administrated every 12 h. Immunohistochemistry against BrdU or Caspase-3 active were performed to determine the number of proliferative or apoptotic cells. Results: Our results showed that phenytoin induces proliferation in the SVZ and the SGZ in a dose-dependent manner. No statistically significant effects on cell proliferation in the SCZ neither in the apoptosis rate at the SVZ, SGZ and SCZ were found. Conclusion: These data indicate that phenytoin promotes a dose-dependent proliferation in the SVZ and SGZ of the adult brain. The clinical relevance of these findings remain to be elucidated.

Effects of Aluminium Chloride on Anxiety-Related Behaviour

Problem statement: Aluminium is presents in many manufactured foods, medicines and is also added to drinking water for purification purposes. It has the potential to be neurotoxic in human and animals but its contribution in Alzhemer�s disease remains contradictory. Anxiety affects one-eighth of the total population world-wide and has become an important area of research interest in psychopharmacology. Approach: The present study was aimed at evaluating the effects that Aluminium chloride could have on anxiety-related Behaviour of Adult wistar Rats. A total of Ten (10) Adult wistar rats were used for this experiment. The wistar rats were divided into five groups: Group I was the control that received distil water, Group II received 475 mg Kg^-1, Group III received 950 mg kg^-1, Group IV received 1,425 mg kg^-1 and Group V received 1,900 mg kg^-1 through oral intubation for duration of Eight weeks. Elevated plus maze was used to assay for anxiety-related behaviour of the wistar rats. The wistar rats were placed at the junction of the four arms of the maze, facing a closed arm, allowed to freely explore the maze and their behavior was recorded simultaneously for 5 m by means of a video camera. Results: Wistar rats treated with Aluminium Chloride had, increased faecal boli, increased number of time crossing close arm entries and increased average time spent in close arms; but decreased time (lesser time) spent in the open arm of the maze when compared with the control group. This in turn implies that the Aluminium treated groups were more anxious than the control groups in exploration of their activities on the Elevated plus maze. Conclusion: It was concluded that Aluminium Chloride exposure has negative effects on anxiety-related behaviour of wistar rats as indicated by increased rate of anxiety in aluminium treated rats.

Motor Imagery and Stroke Neurorehabilitation: An Overview of Basic Concepts and Therapeutic Effects

Problem statement: Motor Imagery (MI), which corresponds to an active process during which the representation of a specific action is internally reproduced into working memory without any motor output. It represents the result of conscious access to the content of a movement intention, which is usually performed unconsciously during movement preparation. Approach: This review study aims to provide information on the current research and main findings related to the potential therapeutic effects of motor imagery on stroke neurorehabilitation. Results: Several studies demonstrate that conscious motor imagery and unconscious motor preparation share common mechanisms and are functionally equivalent, improving recovery of motor skills in stroke patients. Conclusion: In conclusion, motor imagery, proved very useful and effective, with significant results in improvement of motor deficits in post stroke patients. Thus, it is recommended that further studies must be conducted to determine specific parameters such as number and weekly frequency, duration (minutes per session), type (visual or kinesthetic) and the appropriate moment to apply mental practice (phases recovery of pathology), in order to create specific protocols for each treatment phase.

Dementia in Parkinson's Disease: A Clinical Review

Problem statement: Idiopathic Parkinson's Disease (PD) has being increasingly seen as a neuropsychiatric entity and no longer purely neurological, given the frequency and exuberance with which the psychiatric manifestations occurs. Approach: This review will focus on the epidemiology, clinical aspects, differential diagnosis with Alzheimer's Disease (AD) associated with parkinsonism, Dementia with Lewy Bodies (LBD), Progressive Supranuclear Palsy (PSP), Corticobasal Degeneration (CBD), Multiple System Atrophy (MSA), Vascular Parkinsonism and Normal Pressure Hydrocephalus (NPN), underlying mechanisms and treatment of dementia in PD. A literature review of the studies that investigated the dementia in PD was performed. Results: The dementia in PD has being increasingly recognized as a distinct nosological entity. Although specific etiologies for cognitive impairment remain unknown, a symptomatic treatment has been approved and strategies for early intervention are envisioned. Conclusion: Larger scale, placebo controlled clinical trials are needed to be explored in future studies to provide an evidence base to guide the management in dementia associated with PD.

Functional Neuroimaging in Dementia and other Amnesic Disorders: A Radiological Review

Problem statement: The structural and functional neuroimaging have much to contribute to the cognitive neuroscience. Approach: We describe a radiological review of the major dementia syndromes and Mild Cognitive Impairment (MCI), included Alzheimer's disease, Lewy body dementia, Vascular dementia, Front temporal Lobar degeneration, Dementia associated with parkinsonism and other amnesic syndromes. Results: The different syndromes and diseases presenting with dementia have different patterns of brain perfusion abnormalities, it is possible to distinguish them with good specificity with neuroimaging. Conclusion: New imaging techniques carry the hope of revolutionizing the diagnosis of dementia so as to obtain a complete molecular, structural and metabolic characterization, which could be used to improve diagnosis and to stage each patient and follow disease progression and response to treatment. Structural and functional imaging modalities contribute to the diagnosis and understanding of the different dementias.

Improved Application of Paraconsistent Artificial Neural Networks in Diagnosis of Alzheimer's Disease

Problem statement: The visual analysis of Electroencephalogram (EEG) activity has shown useful as a complementary tool in Alzheimer Disease (AD diagnosis) when the diagnosis remains uncertain, in addition to be used in some clinical protocols. However, this analysis is subject to the inherent equipment imprecision, biological artifact, electrical records, and subjective physician interpretation of the visual analysis variation. The Artificial Neural Network (ANN) could be a helpful tool, appropriate to address problems such as prediction and pattern recognition. Approach: In this study, it was used a new class of ANN, namely the Paraconsistent Artificial Neural Network (PANN), which is capable of handling uncertain, inconsistent, and paracomplete information, for recognizing predetermined patterns of EEG activity and to assess its value as a possible complementary method for AD diagnosis. Thirty three AD patients and thirty four controls patients of EEG records were obtained during relaxed wakefulness. It was considered as normal patient pattern, the background EEG activity between 8.0 Hz and 12.0 Hz (with an average frequency of 10.0 Hz), allowing a range of 0.5 Hz. Results: The PANN was able to recognize waves that belonging to their respective bands of clinical use (theta, delta, alpha, and beta), leading to an agreement with the clinical diagnosis at 80% of sensitivity and at 73% of specificity. Conclusion: Supported by results, the PANN could be a promising tool to manipulate EEG analysis, bearing in mind the following considerations: the growing interest of specialists in EEG visual analysis and the ability of the PANN to deal in directly imprecise, inconsistent and paracomplete data, providing an interesting quantitative and qualitative analysis.

Clinical and Functional Profile of Amyotrophic Lateral Sclerosis Patients: A One Year Follow Up

Problem statement: Amyotrophic Lateral Sclerosis (ALS) is a progressive and degenerative disease that affects the anterior horn motor neurons of the spinal cord and pyramidal tracts. In Brazil, there are few epidemiological data on this disease. Recently, some important findings have been reported, allowing a better understanding on the underlying processes of neuronal death, as well as the characteristics of this population. To discuss the clinical and functional profile of a convenience sample of patients with ALS in Rio de Janeiro and Neurology Department-Federal Fluminense University to compare the data with studies of other regions and countries. Approach: We used the Severity and Functional Ability Scale (SFAS) as a clinical and functional indicator for ALS. The modified El Escorial criteria were used to establish the diagnosis. The participants underwent five quarterly assessments during the study period. The research took place at two University Hospitals (Hospital Universitario Antonio Pedro-Universidade Federal Fluminense and Instituto de Neurologia Deolindo Couto-Universidade Federal do Rio de Janeiro) from March 2007 to December 2009. Results: Of the 98 recruited subjects, only 24 have completed all phases of the study. The average age was 52.7�4.1 years. The time between the onset of first symptoms and seeking care services was 11.6�12.:4 months. The time between the first symptoms and the diagnosis was 20.5�8.4 months. Muscle weakness was identified as the initial symptom in most cases. Patients had impaired muscle strength, speech, swallowing, respiratory function and severity stages of SFAS. The disease had different forms of initial presentation (impaired speech, limbs strength, respiratory function or swallowing), time to progression and clinical characteristics in our population. Conclusion: The knowledge on the individual clinical evolution in ALS is of paramount importance for the healthcare team to provide a correct treatment during the decline of the disease and formulate theoretical and conceptual issues, aiming at solving problems in clinical practice.

Effects of Repetitive Transcranial Magnetic Stimulation on Dystonia: An Overview

Problem statement: Repetitive Transcranial Magnetic Stimulation (rTMS) is a noninvasive procedure whereby a pulsed magnetic field stimulates electrical activity in the brain. Dystonia is characterized by several disabling symptoms for which effective, mechanism-based treatments remain elusive. Approach: Consequently, more advanced non-invasive therapeutic methods were required. A possible method to modulate brain activity and potentially viable for use in clinical practice was rTMS. We focus on the basic foundation of rTMS, the effects of rTMS on neuroplasticity and sensorimotor integration and the experimental advances of rTMS that may become a viable clinical application to treat dystonia. Results: The findings showed that rTMS can improve some symptoms associated with dystonia and might be useful for promoting cortical plasticity in dystonic patients. These changes were transient and it is premature to propose these applications as realistic therapeutic options, even though the rTMS technique has shown itself to be, potentially, a modulator of sensorimotor integration and neuroplasticity. Conclusion/Recommendations: Functional imaging of the region of interest could highlight the capacity of rTMS to bring about plastic changes of the cortical circuitry and hint at future novel clinical interventions. We recommend further studies to clearly determine the role of rTMS in the treatment of these conditions. Finally, we must remember that however exciting the neurobiological mechanisms might be, the clinical usefulness of rTMS will be determined by their ability to provide patients with neurological and psychiatric disorders with safe, long-lasting and substantial improvements in quality of life.

Sensory Neuropathy Associated with Glucose Intolerance: A 35 Patients Study

Problem statement: Peripheral neuropathy due to diabetes has been studied for several decades. Until recently, we associate the involvement of peripheral nerves with an inappropriate glycemic control in the most advanced stages of the disease. Currently, it is considered that the onset of the neural injury can occur in the initial phase of this metabolic abnormality, during the period of glucose intolerance. Approach: The clinical aspects of the sensory neuropathy associated to the impaired glucose tolerance were analyzed in 35 Brazilian patients. All patients met the American Diabetes Association (ADA) and the World Health Organization (WHO) criteria for glucose intolerance. Results: We studied 20 male and 15 female, with a mean age of 62.5, ranging from 30-83 years. A distal symmetrical lower limb involvement with positive (neuropathic pain) and/or negative (reduced temperature and pinprick sensations) symptoms and clinical signs of autonomic neuropathy were seen in most patients. The glycemic levels were not related to the severity of the symptoms or to the presence of any specific symptom. Conclusion: The Impaired Glucose Tolerance (IGT) neuropathy can be included in the chronic axonal polyneuropathy and usually the patients suffer from chronic pain and disability before the diagnosis. The determination of the prevalence of symptoms is essential to recognize this disease. The early diagnosis and the aggressive treatment can be crucial for the control, development and progression of the small fiber neuropathy in glucose intolerant patients.