ABSTRACT
The frontoparietal semantic network, encompassing the inferior frontal gyrus and the posterior middle temporal cortex, is considered to be involved in semantic control processes. The explicit versus implicit nature of these control processes remains however poorly understood. The present study examined this question by assessing regional brain responses to the semantic attributes of an unattended stream of auditory words while participants' top-down attentional control processes were absorbed by a demanding visual search task. Response selectivity to semantic aspects of verbal stimuli was assessed via a functional magnetic resonance imaging response adaptation paradigm. We observed that implicit semantic processing of an unattended verbal stream recruited not only unimodal and amodal cortices in posterior supporting semantic knowledge areas, but also inferior frontal and posterior middle temporal areas considered to be part of the semantic control network. These results indicate that frontotemporal semantic networks support incidental semantic (control) processes.
Subject(s)
Semantic Web , Semantics , Brain Mapping , Humans , Prefrontal Cortex/physiology , Temporal Lobe/diagnostic imaging , Temporal Lobe/physiologyABSTRACT
We discuss the diagnostic workup of a 62 year old woman without any significant past medical history. We take this opportunity to point out three aspects : 1. The necessary contextualization of the whole process allowing to avoid unrealistic differentials; 2. The requirement to prioritize the diagnostic tests as a function of their expected contribution to the diagnosis, their invasive characteristic and their availability, including their cost and 3. The evolving character of the diagnostic process that, if needed, has to be reconsidered to integrate the information obtained from the first diagnostic tests and the evolution of the patient.
Nous discutons la démarche sémiologique et diagnostique d'un cas d'ataxie chez une patiente de 62 ans, indemne de tout antécédent médical significatif. A l'occasion de cette vignette diagnostique, nous insistons sur trois aspects : 1. La nécessité de contextualiser la démarche pour éviter d'évoquer des diagnostics différentiels irréalistes; 2. La nécessité de choisir les examens complémentaires pertinents en les hiérarchisant en fonction de la probabilité de contribuer au diagnostic, de leur invasivité et de leur disponibilité, y compris de leur coût et 3. Le caractère évolutif de la démarche diagnostique qu'il faut pouvoir remettre en question au fil des informations que fournissent l'évolution du patient et les résultats des investigations.
Subject(s)
Accidental Falls , Ataxia , Ataxia/diagnosis , Ataxia/etiology , Diagnosis, Differential , Female , Humans , Middle AgedABSTRACT
Light pollution is defined as the abnormal and disturbing nocturnal presence of light, its adverse consequences on flora, fauna, and, ecosystems, and its suspected or proven effects on human health. Light pollution is a quite recent and increasing phenomenon within our society; it leads to a major environmental damage not only on wildlife, but also on human health (cancers, obesity, fatigue, depression...). The solutions to this problem are however simple, efficient and, de facto, inexpensive because they involve a substantial energy saving.
Subject(s)
Circadian Rhythm , Health Status , Light/adverse effects , Photoperiod , Environment , HumansABSTRACT
The hypothalamo pituitary axis, as the true conductor of the endocrine orchestra, is frequently involved in a large variety of pathological conditions such as acromegaly, behavioral disorders, obesity or dwarfism. It is paradoxical to note that, in spite of its importance, this system has been almost ignored by the physiologists of the late centuries. From the physiological conceptions of the physicians and philosophers of antiquity to the theories of the medieval and of the Renaissance physiologists, we will try to understand why the role of pituitary remained so long unrecognized.
Subject(s)
Endocrinology/history , Pituitary Gland/anatomy & histology , Pituitary Gland/physiology , History, 15th Century , History, 16th Century , History, 17th Century , History, 18th Century , History, 19th Century , History, 20th Century , History, Ancient , History, Medieval , HumansABSTRACT
Electroencephalographic activity in the context of disorders of consciousness is a swiss knife like tool that can evaluate different aspects of cognitive residual function, detect consciousness and provide a mean to communicate with the outside world without using muscular channels. Standard recordings in the neurological department offer a first global view of the electrogenesis of a patient and can spot abnormal epileptiform activity and therefore guide treatment. Although visual patterns have a prognosis value, they are not sufficient to provide a diagnosis between vegetative state/unresponsive wakefulness syndrome (VS/UWS) and minimally conscious state (MCS) patients. Quantitative electroencephalography (qEEG) processes the data and retrieves features, not visible on the raw traces, which can then be classified. Current results using qEEG show that MCS can be differentiated from VS/UWS patients at the group level. Event Related Potentials (ERP) are triggered by varying stimuli and reflect the time course of information processing related to the stimuli from low-level peripheral receptive structures to high-order associative cortices. It is hence possible to assess auditory, visual, or emotive pathways. Different stimuli elicit positive or negative components with different time signatures. The presence of these components when observed in passive paradigms is usually a sign of good prognosis but it cannot differentiate VS/UWS and MCS patients. Recently, researchers have developed active paradigms showing that the amplitude of the component is modulated when the subject's attention is focused on a task during stimulus presentation. Hence significant differences between ERPs of a patient in a passive compared to an active paradigm can be a proof of consciousness. An EEG-based brain-computer interface (BCI) can then be tested to provide the patient with a communication tool. BCIs have considerably improved the past two decades. However they are not easily adaptable to comatose patients as they can have visual or auditory impairments or different lesions affecting their EEG signal. Future progress will require large databases of resting state-EEG and ERPs experiment of patients of different etiologies. This will allow the identification of specific patterns related to the diagnostic of consciousness. Standardized procedures in the use of BCIs will also be needed to find the most suited technique for each individual patient.
Subject(s)
Brain Waves/physiology , Brain/physiopathology , Coma/pathology , Persistent Vegetative State/pathology , Brain-Computer Interfaces , Electroencephalography/methods , Electroencephalography/standards , Evoked Potentials/physiology , HumansSubject(s)
Buttocks/abnormalities , Digestive System Abnormalities/diagnosis , Syringomyelia/diagnosis , Adult , Anal Canal/abnormalities , Homeodomain Proteins/genetics , Humans , Low Back Pain/etiology , Male , Mutation , Rectum/abnormalities , Sacrum/abnormalities , Transcription Factors/geneticsABSTRACT
We report the case of a 45 years old woman who experienced two episodes of facial palsy, first on the left side, then on the other. This particular case allows us to discuss the diagnostic process and clinical reasoning to follow in front of this symptomatology -using a didactic questioning- and to briefly review the anatomy of the seventh cranial nerve. Treatment and possible complications are also discussed.
Subject(s)
Facial Nerve Diseases/diagnosis , Facial Paralysis/diagnosis , Acyclovir/therapeutic use , Antiviral Agents/therapeutic use , Diagnosis, Differential , Drug Therapy, Combination , Facial Nerve Diseases/drug therapy , Facial Nerve Diseases/etiology , Facial Paralysis/drug therapy , Facial Paralysis/etiology , Female , Glucocorticoids/therapeutic use , Humans , Methylprednisolone/therapeutic use , Middle Aged , Recurrence , Treatment OutcomeABSTRACT
Alzheimer's disease is the most common neurodegenerative disease encountered in patients over 60 years. By its prevalence and the consequent individual and social loss of function Alzheimer's disease is a major public health problem. With the presentation of a clinical story of Alzheimer's disease in an elderly patient, we propose a diagnostic and therapeutic discussion on this clinical problem. We must adjust the treatment for each patient and overall not omit the non pharmacological therapeutic approaches.
Subject(s)
Alzheimer Disease/diagnosis , Alzheimer Disease/drug therapy , Aged , Alzheimer Disease/psychology , Antioxidants/therapeutic use , Cholinesterase Inhibitors/therapeutic use , Cognition Disorders/diagnosis , Cognition Disorders/drug therapy , Cognitive Behavioral Therapy , Diagnosis, Differential , Dopamine Agents/therapeutic use , Drug Therapy, Combination , Geriatric Assessment , Humans , Male , Psychiatric Status Rating Scales , Risk Factors , Severity of Illness Index , Social SupportABSTRACT
Since their inception in the 1970's, monoclonal antibody therapies became increasingly efficient and common in numerous medical conditions and their use in neurology has been boosted during the last couple of years with the rise of natalizumab (Tysabri). Furthermore, if most monoclonal antibodies currently assessed in neurologic conditions remain considered as experimental, they may soon become first-line approved treatments in a broad range of neuromuscular and demyelinating diseases. Since the introduction of new therapies is likely to unravel specific adverse events and sui generis iatrogenic disorders, it is important to be able to recognize the side-effects of monoclonal antibodies delivered for neurological or non-neurological diseases.
Subject(s)
Antibodies, Monoclonal/therapeutic use , Nervous System Diseases/drug therapy , Neuroprotective Agents/therapeutic use , Alemtuzumab , Antibodies, Monoclonal, Humanized , Antibodies, Monoclonal, Murine-Derived , Antibodies, Neoplasm/therapeutic use , Daclizumab , Etanercept , Humans , Immunoglobulin G/therapeutic use , Infliximab , Natalizumab , Receptors, Tumor Necrosis Factor/therapeutic use , RituximabABSTRACT
The discovery of dystonia as an isolated abnormality or as a symptom involved in a larger neurological or systemic disease is not unfrequent in clinical practice. Dystonia can occur at any age, from childhood to elderly. A rapid diagnosis is very important to optimise the managing of those chronical and often invalidating diseases. We should point out the pre-eminent role played by MRI techniques in the diagnosis and follow-up of dystonic patients. We present here an overview of most frequent dystonic troubles and an attempt of classification to simplify their diagnosis.
