As a rhythmic neural activity, neural oscillation exists all over the nervous system, in structures as diverse as the cerebral cortex, hippocampus, subcortical nuclei and sense organs. This review firstly presents some evidence that synchronous neural oscillations in theta and gamma bands reveal much about the origin and nature of cognitive processes such as learning and memory. And then it introduces the novel analyzing algorithms of neural oscillations, which is a directionality index of neural information flow (NIF) as a measure of synaptic plasticity. An example of application used such an analyzing algorithms of neural oscillations has been provided.
Animals ; Biological Clocks ; Brain ; physiology ; Cognition ; physiology ; Humans ; Learning ; physiology ; Memory ; physiology ; Nervous System Physiological Phenomena ; physiology ; Neural Pathways ; physiology ; Neuronal Plasticity ; physiology ; Synapses ; physiology ; Theta Rhythm ; physiology

BACKGROUND: Anesthesia induces the spectral changes in EEG. Attempts to relate these spectral changes to adequacy of anesthesia have been hindered due to the complex waveforms of EEG. The objective of this investigation is to monitor the awareness of patients during cesarean section by means of EEG spectral analysis. METHODS: 20 patients for cesarean section aged from 24 to 39 and ASA class I or II, were maintained with O2(50%)-N2O(50%)-enflurane(0.8%). And they were administered with midazolam(0.07 mg/kg) in group I(n=6), fentanyl(1 microgram/kg) in group II(n=7), and fentanyl(2 microgram/kg) in group III(n=7) after birth. The density of each spectral band in EEG (delta 1-3.25 Hz, theta 3.5-7.75 Hz, alpha 8-12.15 Hz and beta 13-31.75Hz) was analyzed to derive total density, delta ratio and median power frequency. RESULTS: The spectral data demonstrated that the alpha rhythm was dominant in pre-induction period and beta rhythm was abundant both in the immediate post-induction period and after birth for all three groups. Delta ratio and median power frequency decreased after injection of midazolam and fentanyl in all three groups. None of patients could recall the memory about experience during cesarean section. CONCLUSIONS: These findings indicate that EEG spectral analysis is potentially useful to determine the changes of cerebroelectrical activity but difficult to monitor the awareness of patients during cesarean section.
Alpha Rhythm ; Anesthesia ; Anesthetics ; Anesthetics, Intravenous* ; Beta Rhythm ; Cesarean Section* ; Electroencephalography* ; Enflurane ; Female ; Fentanyl ; Humans ; Isoflurane ; Memory ; Midazolam ; Parturition ; Pregnancy

OBJECTIVE: To determine the effect of cold air therapy on relieving spasticity, the optimal intramuscular temperature, and the duration of spasticity relief. METHOD: Twenty-three 4 months old Korean white rabbits weighing 2 to 3 kg were used. After posterior laminectomy at thoracolumbar junction, the spinal cord was completely transected. After spasticity occurred, cold air was applied to the triceps surae muscles for 30 minutes at three different intramuscular temperatures (32.5, 30, and 25degrees C). Spasticity was measured pre-treatment, immediately following treatment, after 30 minutes, and after 60 minutes. Clinical parameters (muscle tone, deep tendon reflex, ankle clonus, and Babinski's sign) and electrophysiologic parameters (F/M ratio and H/M ratio) were measured. RESULT: Muscle tone and Babinski's sign significantly decreased immediately following treatment in the 32.5degrees C group, immediately following treatment and after 30 minutes in the 30degrees C and 25degrees C group. Deep tendon reflex and ankle clonus significantly decreased immediately following treatment in the 32.5degrees C group, immdiately following treatment, after 30 minutes in the 30degrees C group, immediately following treatment, after 30 minutes and after 60 minutes in the 25degrees C group. The F/M ratio and H/M ratio were not significantly affected in the 32.5degrees C group but decrease immediately following treatment in the 30degrees C and 25degrees C groups. Compound motor unit action potentials were not evoked in 6 out of 16 cases (37.5%) in the 25degrees C group, resulting in blockage of conduction. CONCLUSION: To relieve spasticity with cold air therapy, the intramuscular temperature should be maintained at 30degrees C. The duration of spasticity relief lasted from 30 minutes to one hour after cold air therapy.
Action Potentials ; Ankle ; Humans ; Infant ; Laminectomy ; Muscle Spasticity* ; Muscles ; Rabbits ; Reflex, Babinski ; Reflex, Stretch ; Spinal Cord ; Spinal Cord Injuries

Hippocampal neuronal network oscillation is closely related to the memory, anxiety and behavioral inhibition of mammalian. The cognitive decline and behavioral disinhibition in the patients with Alzheimer's disease (AD) may be relevant to amyloid β protein (Aβ)-induced impairment in hippocampal neuronal cooperative activity. However, it is not well known whether intrahippocampal injection of Aβ could induce behavioral disinhibition and neuronal network disorder, as well as cognition decline in animals. In the present study, we observed the effects of intracerebral injection of Aβ(1-42) on the spatial memory and behavioral inhibition of rats by using Morris water maze and elevated plus-maze tests. Further, we analyzed hippocampal theta rhythm by recording hippocampal local field potential. The results showed that: (1) bilateral hippocampal injection of Aβ(1-42) reduced the anxious behavior of rats, with a significant behavioral disinhibition in the elevated plus-maze test, representing as an increase in the mean entering times and mean residence time in the open arm; (2) Aβ(1-42) injection resulted in a significant impairment of spatial memory in rats, with significantly increased mean escape latencies in hidden platform test; (3) Aβ(1-42) disrupted the induction of theta rhythm induced by tail pinch, with a significant reduction in the peak power, not the peak power frequency of the theta rhythm. These experimental results indicate that intrahippocampal injection of Aβ(1-42) can induce behavioral disinhibition and theta rhythm suppression, as well as spatial memory impairment in rats, which suggests that the cognition deficits and behavior impairments in AD are probably associated with the Aβ-induced disruption of hippocampal theta rhythm and consequent down-regulation of synaptic plasticity.
Amyloid beta-Peptides ; adverse effects ; Animals ; Down-Regulation ; Hippocampus ; physiopathology ; Maze Learning ; Neuronal Plasticity ; Peptide Fragments ; adverse effects ; Rats ; Spatial Memory ; Theta Rhythm

For expressing the condolences on the passing away of Dr. Hsiang-Tung Chang, one of the distinguished members of the Chinese Academia of Sciences, the pioneer studies on cortical dendritic potentials that Dr. Chang carried out in the 1950s and the prosperous progresses since then, especially, concerning the modifications of synaptic plasticity by the dendritic back-propagating action potentials were briefly reviewed.
Action Potentials ; Dendrites ; physiology ; Humans ; Neuronal Plasticity

Hereditary spastic paraplegia(HSP) is a familial disorder which is inherited by autosomal dominant, autosomal recessive or sex linked pattern. Strumpell first described a familial case of spastic paraplegia characterized by progressive weakness and spasticity of the lower limbs. We have experienced two cases of hereditary spastic paraplegia with mental retardation and extrapyramidal symptoms with variable severity. They were sisters. Physical examination revealed increased deep tendon reflexes in all four extremities with extensor plantar reflex, and sensory losses mainly affecting joint position and vibration sensations. One case was dysmorphic. The pattern of inheritance was uncertain but considered as an autosomal recessive type. Electrodiagnostic study revealed mild slownesses in motor conduction velocities, reduced amplitude of sensory nerve action potentials and profuse abnormal spontaneous activities in distal lower extremity muscles. Somatosensory evoked potentials were not obtainable from both lower extremity stimulations, but attenuated responses without delayed latencies were obtainable from both upper extremity stimulations.
Action Potentials ; Evoked Potentials, Somatosensory ; Extremities ; Humans ; Intellectual Disability ; Joints ; Lower Extremity ; Muscle Spasticity ; Muscles ; Paraplegia ; Physical Examination ; Reflex, Babinski ; Reflex, Stretch ; Sensation ; Siblings ; Spastic Paraplegia, Hereditary* ; Upper Extremity ; Vibration ; Wills

No abstract available.
Guillain-Barre Syndrome* ; Ophthalmoplegia* ; Reflex, Babinski*

By using echolocation system echolocating bats have the ability to complete the tasks of detection, localization and classification of the targets. Among the three fundamental tasks, the study of how bats use echolocation to classify targets was investigated later, and most of previous studies were focused on the analysis of simple targets. However, the echoes that bats received are mostly returning from complex objects or structures, which are so complex that they must be described by stochastic statistical approach. In recent years, the study on classification of complex echoes returning from different plants in frequency modulation (FM) bats has made significant progress. In this review article, we will briefly introduce and comment on some progress of studies based on the behavioral evidence, acoustic cues, relevant classification models, and neural bases underlying different classification cues to distinguish plants through classification of echoes in FM bats.
Animals ; Chiroptera ; physiology ; Echolocation ; Nervous System Physiological Phenomena

The purpose of this study was to investigate the trait cortical arousal level, measured by extraversion-introversion, in schizophrenics. Subjects in this study were 231 (chronic schizophrenics= 78, acute schizophrenics= 62, and normal persons= 91). All subjects were asked to respond to extraversion-introversion subtest scale in the korean EPQ(Korean Version Eysenck Personality Questionnaire). Collected data were analyzed by using the. t-test and one-way analysis of variance. Results were as follows: 1) Trait cortical arousal level of chronic schizophrenics, which was measured by extraversion-introversion subtest scale in the Korean EPQ, was statistically higher than that. of. acute schizophrenics and normals. 2) Acute schizophrenics and normals were not significantly different in the trait cortical arousal level. However, the trait cortical arousal level of chronic schizophrenics was higher than that of acute schizophrenics. Therefore, it may state that the trait cortical arousal level of schizophrenics is getting higher when schizophrenic symptoms become more chronic.
Arousal

The studying on interrelation and interaction among blood-vessel network, nerve network and immune network is considered to be the key to reveal the mechanism of acupuncture treatment and the essence of meridians. A strip-like compound structure of mast cells, blood vessel and nerve network is observed in acupoint area. From its systematics nature and correlation with acupuncture effect and meridian phenomena, it is believed that the structure of mast cells, blood vessel and nerve network is an interactive system with interrelation and interaction among each other, and is an essential site and pivot to produce and transport matter, energy and information, and is the core structure of acupoint.
Acupuncture Points ; Animals ; Blood Vessels ; physiology ; Humans ; Immune System ; immunology ; Meridians ; Nervous System Physiological Phenomena