关键词： neurophysiology   swallowing   deglutition   central pattern generator   electromyography   functional brain mapping  

摘要： Swallowing is a complex motor event that is difficult to investigate in man by neurophysiological experiments. For this reason, the characteristics of the brain stem pathways have been studied in experimental animals. However, the sequential and orderly activation of the swallowing muscles with the monitoring of the laryngeal excursion can be recorded during deglutition. Although influenced by the sensory and cortical inputs, the sequential muscle activation does not alter from the perioral muscles caudally to the cricopharyngeal sphincter muscle. This is one evidence for the existence of the central pattern generator for human swallowing. The brain stem swallowing network includes the nucleus tractus solitarius and nucleus ambiguus with the reticular formation linking synaptically to cranial motoneuron pools bilaterally. Under normal function, the brain stem swallowing network receives descending inputs from the cerebral cortex. The cortex may trigger deglutition and modulate the brain stem sequential activity. The voluntarily initiated pharyngeal swallow involves several cortical and subcortical pathways. The interactions of regions above the brain stem and the brain stem swallowing network is, at present, not fully understood, particularly in humans. Functional neuroimaging methods were recently introduced into the human swallowing research. It has been shown that volitional swallowing is represented in the multiple cortical regions bilaterally but asymmetrically. Cortical organisation of swallowing can be continuously changed by the continual modulatory ascending sensory input with descending motor output. Significance: Dysphagia is a severe symptom complex that can be life threatening in a considerable number of patients. Three-fourths of oropharyngeal dysphagia is caused by neurological diseases. Thus, the responsibility of the clinical neurologist and neurophysiologist in the care for the dysphagic patients is twofold. First, we should be more acquainted with

关键词： Pelvic Floor   Urinary Incontinence   Stress   Neurophysiology - biologicfunction  

摘要： Headline This is a longitudinal study of a cohort of primigravidae recruited between 1985 and 1987 and followed up 7 and 15 years later. Pelvic floor neurophysiology was performed and questionnaires were administered to determine the natural history of stress incontinence and to establish whether pelvic floor denervation after the first delivery is associated with symptoms of stress urinary incontinence in the future. Objectives To study the natural history of stress urinary incontinence arising during the first pregnancy, to determine whether postnatal pelvic floor denervation progresses with time and whether it predisposes to stress urinary incontinence in the future. Design Prospective longitudinal cohort study. Setting Tertiary referral urogynaecology unit. Sample Cohort of 96 primigravidae studied prospectively between 1985 and 1987 and followed up 7 years (n = 76) and 15 years (n = 55) later. Methods Urinary incontinence symptoms were recorded and pelvic floor neurophysiology was performed antenatally and postnatally between 1985 and 1987. Repeat neurophysiological tests and questionnaires were completed by those relocated 7 and 15 years later. Main outcome measure Symptoms of stress urinary incontinence. Secondary outcomes Symptoms of urge urinary incontinence and anal incontinence;motor unit potential duration and pudendal nerve terminal latency;vaginal squeeze pressure measured by perineometry. Results Prevalence of stress incontinence was highest during pregnancy and had increased seven years after the first postnatal period (P = 0.0129). Two-thirds of women with antenatal stress incontinence had stress incontinence 15 years later. One-third of women with stress incontinence at any time appear to undergo resolution of symptoms. Motor unit potential duration increased at seven years (P = 0.036). Vaginal squeeze pressure improved during the same period (P = 0.0007). Conclusions When stress urinary incontinence arises during the first pregnancy, the risk of s

关键词： age dependency   basal ganglia-thalarnocortical circuit   DA neuron   5HT neuron   neurophysiology   Tourette's syndrome (TS)  

摘要： At present the neurophysiology of Tourette's syndrome (TS) has been investigated largely from two perspectives;one for evaluation of the dysfunction of the cerebral cortex and the other for clarification of the neuronal mechanisms that underlie tics and related symptoms. For the former the following examinations have been conducted: quantitative analyses of scalp electroencephalography (EEG), premovement EEG potentials, contingent negative variation, transcranial magnetic stimulation, and neuroirnaging studies, including echo-planar images and positron emission tomography scans. These explorations have revealed the likely involvement of the subcortical and the cortical structures, particularly of the basal ganglia, in the pathophysiology of TS. For the latter, surface electromyography, evoked potentials, saccadic eye movements, and polysomnographies have been performed, and again have suggested a dysfunction of the basal ganglia and the brainstem neurons in TS patients. These neurophysiological studies suggest dysfunction of both motor and non-motor basal ganglia-thalamocortical circuitries in TS patients, which is hypothesized to be caused by hypofunction of the dopamine (DA) neurons associated with DA receptor supersensitivity, a well as hypofunction of the serotonergic neurons of the brainstem. Polysommographical examination suggests that the dysfunction of the nigrostriatal (NS)-DA neurons is not a progressive process, but that the dysfunction is closely associated with an early occurrence of the developmental decrement of the activities of the NS-DA system to mature in a normal fashion. The associated DA receptor supersensitivity is assumed to be a consequence of this developmental abnormality and not due to denervation supersensitivity. (C) 2003 Elsevier Science B.V. All rights reserved.

关键词： .primarily   exert   Castration   penile   Neurophysiology of Erectile   androgenic control  

关键词： 亚临床肝性脑病   电生理学   神经心理学   诊断  

关键词： 神经外科   术后   早期康复   康复医学   脑损伤   神经生理学  

摘要： 康复医学是由医学与残疾学、心理学、社会学、工程学等相互渗透而成的跨科性学科,它的具体任务是对残疾和功能障碍进行预防、评估诊断、治疗和处理.在大多数人,包括临床医生的心目中康复是治疗完成后的事.神经外科手术在切除病灶、治疗疾病和损伤的同时,也会给神经组织带来损害.

关键词： Amygdala   Dopamine   Emotion   Episodic memory   Hippocampus   Hunger   Inferior temporal cortex   Object recognition   Orbitofrontal cortex   Prefrontal cortex   Punishment   Reward   Short-term memory   Taste  

摘要： The inferior temporal visual cortex provides invariant representations of objects. The computations underlying this can be understood in the framework of a hierarchical series of competitive networks in the ventral visual stream which learn invariant representations by using a short-term memory trace to extract properties of the visual input that are invariant over short periods and are thus statistically likely to be from the same object. One set of outputs from the inferior temporal cortex is to the orbitofrontal cortex and amygdala, which are involved in representing primary rewards and punishers (such as taste, pleasant touch, and pain), and in associating previously neutral visual stimuli with these primary reinforcers. In that emotions can be defined as states elicited by reinforcers, these functions of the orbitofrontal cortex and amygdala provide a basis for understanding how emotion is implemented in the brain. A second output of the inferior temporal cortex is to the hippocampal system, which is implicated in episodic memory and in spatial function. A third output of the inferior temporal visual cortex is to the prefrontal cortex, which is involved in short-term memory and attentional processes. The combined neurophysiological and computational approach taken to these issues provides a way of understanding how these systems actually operate in the brain to implement object perception, emotion, and long- and short-term memory. © 2003, Elsevier Inc. All rights reserved.

关键词： 时序特征   听神经   自发发放模型   生理模型   听觉系统   外部统计特征   神经生理学   声音信号处理  

摘要： 听神经发放时序在听信息编码中起重要作用,要认识和运用听觉系统对听神经发放时序特征的利用机制必须对听神经发放时序特征有认识,但是已有的随机过程数学模型均不能很好地反映听神经发放时序特征。而关于发放的生理模型,如Hodgkin-Huxley方程、Meddis模型对发放过程的描述均是决定性的、连续性的,不能反映生理过程的离散性和发放过程的随机性。本文基于神经发放生理过程,通过对神经发放条件以及自发发放时神经递质释放时序的描述,建立了一个简单自发发放模型。模型在很好地反映听神经自发发放时序外部统计特征的同时,所得到的神经递质的释放速率在生理上也是合理的。模型还能对纯音激励时听神经的锁相发放做出定性解释,可作为进一步研究反映时序特征的有激励发放模型的基础。

关键词： GnRH   种类   调控机制   降解   合成   促性腺激素释放激素   神经生理学  

摘要： 主要对促性腺激素释放激素的种类、合成与降解,调控机制及应用等方面的最新研究动态作了简要综述。

关键词： anticipatory anxiety   steady state probe topography   SSPT   BOLD   electrophysiology   electric shock   healthy human participants  

摘要： The precise role of the cortex in human anxiety is not well characterised. Previous imaging research among healthy controls has reported alterations in regional cerebral blood flow (rCBF) within the prefrontal and temporal cortices during periods of anxious anticipation;however, the temporal dynamics of this activity has yet to be examined in detail. The present study examined cortical Steady State Probe Topography (SSPT) changes associated with anticipatory anxiety (AA), allowing examination of the temporal continuity and the excitatory or inhibitory nature of AA activations. We recorded Steady State Visually Evoked Potentials (SSVEPs) at 64 scalp locations, skin conductance. and self reported anxiety among 26 right-handed males while relaxed and during the anticipation of an electric shock. Relative to the baseline condition, the AA condition was associated with significantly higher levels of self-reported anxiety and increased phasic skin conductance levels. Across the seven second imaging window, AA was associated with increased SSVEP latency within medial anterior frontal, left dorsolateral prefrontal and bilateral temporal regions. In contrast, increased SSVEP amplitude and decreased SSVEP latency were observed within occipital regions. The observed SSVEP latency increases within frontal and temporal cortical regions are suggestive of increased localised inhibitory processes within regions reciprocally connected to subcortical limbic structures. Occipital SSVEP latency decreases are suggestive of increased excitatory activity. SSVEP amplitude increases within occipital regions may be associated with an attentional shift from external to internal environment. The current findings provide further support for the involvement of frontal, anterior temporal, and occipital cortical regions during anticipatory anxiety, and suggest that both excitatory and inhibitory processes are associated with AA alterations. (C) 2003 Elsevier Inc. All rights reserved.