关键词： NEUROPHYSIOLOGY   NEUROSCIENCES -- History  

摘要： Johannes Müller was the founder of the first school of physiology in Germany. His anatomical, morphological and physiological research as well as his epistemological view of scientific medicine opened the way to a deeper understanding of the structure and the function of the organism. With important discoveries like the law of sense energy, the reflex movement and the definition of different organic stimuli, he enriched the knowledge of neuroanatomy, neurophysiology and sensory physiology and smoothed the way to an experimental physiology. All his famous students like Hermann von Helmholtz, Emil Du Bois-Reymond, Ernst Brücke, Jakob Henle, Robert Remak, Rudolf Virchow and Ernst Haeckel solved many crucial research problems, which Müller identified and pointed out to them as open questions, due to the insufficient methods of investigation. Müller's research method, epistemological view of biological sciences, and his open-minded personal style encouraged the development of new methods adapted to particular problems.

关键词： Saccade   Decision   Primate   Oculomotor   Perception   Cognition  

摘要： Imagine the decisions you might make while playing a simple game like 'matching pennies.' At each play, you and your opponent, say the mathematician John vonNeumann, each lay down a penny heads or tails up. If both pennies show the same side, vonNeumann wins, if not, you win. Before each play, you have the subjective experience of deciding what to do: of choosing whether to play heads or tails. Although decisions like these are not yet understood at a physiological level, progress has been made towards understanding simple decision making in at least one model system: the primate neural architecture that uses visual data and prior knowledge about patterns in the environment to select and execute saccades. Both the visual system and the brainstem circuits that control saccadic eye movements are particularly well understood, making it possible for physiologists to begin to study the connections between these sensory and motor processes at a level of complexity that would be impossible in other less well understood systems.

关键词： neural circuits   synchronization  

摘要： The spinal circuits of zebrafish, and the rhythmic movement generated by their activation, elicit the familiar swimming action of these fish. Synchronous rhythmic activity of neurons is believed to be important for the establishment and consolidation of proper synaptic connections.

关键词： spasms   neurophysiology   ictal patterns   subcortical phenomenon   polygraphic studies  

摘要： Spasms are a form of epileptic seizure typical of infancy. From a clinical point of view, the child presents a flexor-extensor movement involving the trunk and limbs and lasting about 1 s. Although asymmetry can be present, the seizure involves both sides of the body. The ictal discharge most frequently associated with spasms in West syndrome (WS) is a diffuse triphasic slow high-amplitude wave and less frequently a low-amplitude brief rapid rhythm. The origin of the spasm in WS and classification as either partial or generalized seizure are the subject of much discussion. Factors supporting partial origin include: interictal electroencephalography (EEG) characterized by multifocal anomalies;high incidence of focal cortical lesions and remission of spasms following surgical removal of focal lesions. Factors supporting generalized origin are: clinical involvement of the entire body;mostly generalized ictal EEG pattern;existence of idiopathic cases and possibility of spasms immediately following a partial seizure like a particular form of secondary generalization. In our opinion, the categories of 'partial' and 'generalized' seizures are not applicable to spasms in WS. Sometimes the spasms in WS can be observed together with other types of partial or generalized seizures. Polygraphic recordings have demonstrated that despite being clinically similar, each spasm is different from the other because of a variable sequence in muscular contraction. These data support the peculiar nature of the spasms in WS that could be a subcortical phenomenon that requires a cortical trigger. (C) 2001 Elsevier Science B.V. All rights reserved.

关键词： 心理生理学   人类  

关键词： Noise -- Physiological effect   Signal detection (Psychology)   Auditory evoked response   Evoked potentials (Electrophysiology)   Neurophysiology  

摘要： Discusses research being done on the effect of noise on improving signal detection. Reference to study by W. C. Stacey and D. M. Durand, published in the 2001 issue of 'Journal of Neurophysiology'; Approach taken to evoke subthreshold synaptic potentials in CA1 neurons; Effect of the noise on the signal-to-noise ratio.

关键词： gain fields   computational neuroscience   computer model   parietal cortex   neglect   coordinate transformations  

摘要： Gain modulation is a nonlinear way in which neurons combine information from two (or more) sources, which may be of sensory, motor, or cognitive origin. Gain modulation is revealed when one input, the modulatory one, affects the gain or the sensitivity of the neuron to the other input, without modifying its selectivity or receptive field properties. This type of modulatory interaction is important for two reasons. First, it is an extremely widespread integration mechanism;it is found in a plethora of cortical areas and in some subcortical structures as well, and as a consequence it seems to play an important role in a striking variety of functions, including eye and limb movements, navigation, spatial perception, attentional processing, and object recognition. Second, there is a theoretical foundation indicating that gain-modulated neurons may serve as a basis for a general class of computations, namely, coordinate transformations and the generation of invariant responses, which indeed may underlie all the brain functions just mentioned. This article describes the relationships between computational models, the physiological properties of a variety of gain-modulated neurons, and some of the behavioral consequences of damage to gain-modulated neural representations.

关键词： Raphe nuclei   signal transduction   neuromodulation   neuronal network   prolactin   depression  

摘要： Serotonin (5-HT), one of the evolutionary oldest central neurotransmitters, regulates the most extensive modulatory behavioral system in the brain of vertebrates. 5-HT projections are influenced by extrinsic and intrinsic impulses from different cortical brain areas, which reach Raphe nuclei over feedback loops, containing external and internal body information about planning, evaluation, motivation or excitation. Serotonergic neurotransmission adjusts neuromodulation with consecutive adequate stimulation of the neuronal network. This depends on appropriate equilibration of presynaptic 5-HT storage and release but also on 5-HT reuptake from synaptic cleft by 5-HT transporters. The associated pre and postsynaptic 5-HT receptor cooperation, postsynaptic second messenger response and phosphoinositide signaling mediated by postsynaptic 5-HTz receptor subpopulation alter signal transduction in which myristolated alanine rich C kinase substrate is prominently involved in regulation of further central 5-HT areas in the brain and corresponding functional neuronal changes. Even though the central function of 5-HT neurotransmission is dominating in the multifold behavioral regulation, peripheral concentration of tryptophan (TRP) adjusted by hepatic and non-hepatic TRIP pyrrolase, TRP liberation from albumin especially by adrenergic stimulation of free fatty acids, TRP passage across the blood-brain barrier and TRP hydroxylase activity are also important for appropriate 5-HT neurotransmission as they affect central 5-HT synthesis. The high adaptability of 5-HT neurotransmission is able to compensate neuromodular dysfunctions in the brain by mechanisms which mediate 5-HT biosynthesis, release, reuptake, pre and postsynaptic receptor stimulation with the respective second messenger response and signal transduction to various areas of the brain which are involved in regulation of behavior, mood, memory, learning and attenuation of obsession, depending on the different vigilance s

关键词： Fibromyalgia   Muscle Spindle   Trigger Point   Cervical Dystonia   Myofascial Pain Syndrome  

摘要： This article discusses the neurophysiology of myofascial pain syndrome. The local twitch response is a characteristic finding of this condition;it is activated by snapping palpation, pressure, or needle insertion at the trigger point. It is manifested by a burst of activity in the muscle band that contains the activated trigger point. No activity is seen at other muscles bands. Data from experiments with the rabbit indicate that this is a spinal reflex, as it is abolished by transection of the motor nerve innervating the trigger point and infusion of lidocaine. Transection of the spinal cord above the level of the trigger point fails to permanently alter the trigger point response. Needle examination recordings from trigger points show low-voltage spontaneous activity and activity resembling end-plate spikes. This activity is reduced with infusion of phentolamine and local intramuscular infusions of phenoxybenzamine. There are four hypotheses to explain the findings seen at the trigger point. The first is that trigger points are found at the muscle spindle. While this theory may explain the effects of alpha-adrenergic antagonists at the trigger point, it does not fully explain the electromyographic (EMG) findings recorded at the trigger point. The second theory is that trigger points represent hyperactive end-plate regions, as the EMG activity recorded at trigger points resembles that described at the end-plate region. Other theories that either deny the existence of myofascial pain syndrome or believe it represents a focal dystonia are also discussed.

关键词： 腹主动脉瘤   血管外科手术   心理生理学   生活质量  

摘要： 为探讨腹主动脉瘤患者手术前后心理因素的变化及其对患者生活质量的影响 ,选择 1999年 1月～2 0 0 0年 4月经手术治疗的腹主动脉瘤患者中能理解并独立完成答卷者 2 4例 ,在入院当天和出院前 1天分别利用SCL 90心理测试表进行问卷调查。结果发现 ,术前与术后患者在综合情况、抑郁、焦虑、强迫症状和恐怖等方面均存在显著差异 (P <0 .0 5 )。说明腹主动脉瘤的手术治疗不仅能达到预防腹主动脉瘤破裂的目的 ,而且可以缓解患者的精神压力 。