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Alpha Waves
Alpha waves, or the alpha rhythm, are neural oscillations in the frequency range of 8–12 Hz likely originating from the synchronous and coherent ( in phase or constructive) neocortical neuronal electrical activity possibly involving thalamic pacemaker cells. Historically, they are also called "Berger's waves" after Hans Berger, who first described them when he invented the EEG in 1924. Alpha waves are one type of brain waves detected by electrophysiological methods, e.g., electroencephalography (EEG) or magnetoencephalography (MEG), and can be quantified using power spectra and time-frequency representations of power like quantitative electroencephalography (qEEG). They are predominantly recorded over parieto-occipital brain and were the earliest brain rhythm recorded in humans. Alpha waves can be observed during relaxed wakefulness, especially when there is no mental activity. During the eyes-closed condition, alpha waves are prominent at parietal locations. Atte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eeg Alpha
Electroencephalography (EEG) is a method to record an electrogram of the spontaneous electrical activity of the brain. The bio signals detected by EEG have been shown to represent the postsynaptic potentials of pyramidal neurons in the neocortex and allocortex. It is typically non-invasive, with the EEG electrodes placed along the scalp (commonly called "scalp EEG") using the International 10–20 system, or variations of it. Electrocorticography, involving surgical placement of electrodes, is sometimes called "intracranial EEG". Clinical interpretation of EEG recordings is most often performed by visual inspection of the tracing or quantitative EEG analysis. Voltage fluctuations measured by the EEG bio amplifier and electrodes allow the evaluation of normal brain activity. As the electrical activity monitored by EEG originates in neurons in the underlying brain tissue, the recordings made by the electrodes on the surface of the scalp vary in accordance with their orien ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lateral Geniculate Nucleus
In neuroanatomy, the lateral geniculate nucleus (LGN; also called the lateral geniculate body or lateral geniculate complex) is a structure in the thalamus and a key component of the mammalian visual pathway. It is a small, ovoid, Anatomical terms of location#Dorsal_and_ventral, ventral projection of the thalamus where the thalamus connects with the optic nerve. There are two LGNs, one on the left and another on the right side of the thalamus. In humans, both LGNs have six layers of neurons (grey matter) alternating with optic fibers (white matter). The LGN receives information directly from the ascending retinal ganglion cells via the optic tract and from the reticular activating system. Neurons of the LGN send their axons through the optic radiation, a direct pathway to the primary visual cortex. In addition, the LGN receives many strong feedback connections from the primary visual cortex. In humans as well as other mammals, the two strongest pathways linking the eye to the bra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Major Depression
Major depressive disorder (MDD), also known as clinical depression, is a mental disorder characterized by at least two weeks of pervasive low mood, low self-esteem, and loss of interest or pleasure in normally enjoyable activities. Introduced by a group of US clinicians in the mid-1970s, the term was adopted by the American Psychiatric Association for this symptom cluster under mood disorders in the 1980 version of the ''Diagnostic and Statistical Manual of Mental Disorders'' (DSM-III), and has become widely used since. The disorder causes the second-most years lived with disability, after lower back pain. The diagnosis of major depressive disorder is based on the person's reported experiences, behavior reported by family or friends, and a mental status examination. There is no laboratory test for the disorder, but testing may be done to rule out physical conditions that can cause similar symptoms. The most common time of onset is in a person's 20s, with females affec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chronic Fatigue Syndrome
Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a disabling Chronic condition, chronic illness. People with ME/CFS experience profound fatigue that does not go away with rest, as well as sleep issues and problems with memory or concentration. The Pathognomonic, hallmark symptom is post-exertional malaise (PEM), a worsening of the illness which can start immediately or hours to days after even minor physical or mental activity. This "crash" can last from hours or days to several months. Further common symptoms include orthostatic intolerance, dizziness or faintness when upright and pain. The cause of the disease is unknown. ME/CFS often starts after an infection, such as infectious mononucleosis, mononucleosis. It can run in families, but no genes that contribute to ME/CFS have been confirmed. ME/CFS is associated with changes in the nervous and immune systems, as well as in energy production. Diagnosis is based on distinctive symptoms, and a differential diag ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sleep Disorder
A sleep disorder, or somnipathy, is a medical disorder affecting an individual's sleep patterns, sometimes impacting physical, mental, social, and emotional functioning. Polysomnography and actigraphy are tests commonly ordered for diagnosing sleep disorders. Sleep disorders are broadly classified into dyssomnias, parasomnias, circadian rhythm sleep disorders involving the timing of sleep, and other disorders, including those caused by medical or psychological conditions. When a person struggles to fall asleep or stay asleep without any obvious cause, it is referred to as insomnia, which is the most common sleep disorder. Other sleep disorders include sleep apnea, narcolepsy, hypersomnia (excessive sleepiness at inappropriate times), sleeping sickness (disruption of the sleep cycle due to infection), sleepwalking, and night terrors. Sleep disruptions can be caused by various issues, including teeth grinding (bruxism) and night terrors. Managing sleep disturbances that are seconda ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fibromyalgia
Fibromyalgia (FM) is a functional somatic syndrome with symptoms of widespread chronic pain, accompanied by fatigue, sleep disturbance including awakening unrefreshed, and Cognitive deficit, cognitive symptoms. Other symptoms can include headaches, Abdominal pain, lower abdominal pain or cramps, and Depression (mood), depression. People with fibromyalgia can also experience insomnia and extreme sensitivity. The causes of fibromyalgia are unknown, with several pathophysiologies proposed. People with fibromyalgia are sometimes accused of imagining their symptoms. Fibromyalgia was first recognised in the 1950s, and defined in 1990, with updated criteria in 2011, 2016, and 2019. Fibromyalgia is estimated to affect 2 to 4% of the population. Women are affected more than men. Rates appear similar across areas of the world and among varied cultures. Symptoms of fibromyalgia are persistent in most patients. The treatment of fibromyalgia is Symptomatic treatment, symptomatic an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quantitative Electroencephalography
Quantitative electroencephalography (qEEG or QEEG) is a field concerned with the numerical analysis of electroencephalography (EEG) data and associated behavioral correlates. Details Techniques used in digital signal analysis are extended to the analysis of electroencephalography (EEG). These include wavelet analysis and Fourier analysis, with new focus on shared activity between rhythms including phase synchrony (coherence, phase lag) and magnitude synchrony (comodulation/correlation, and asymmetry). The analog signal comprises a microvoltage time series of the EEG, sampled digitally and sampling rates adequate to over-sample the signal (using the Nyquist principle of exceeding twice the highest frequency being detected). Modern EEG amplifiers use adequate sampling to resolve the EEG across the traditional medical band from DC to 70 or 100 Hz, using sample rates of 250/256, 500/512, to over 1000 samples per second, depending on the intended application. QEEG can be perf ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mindfulness
Mindfulness is the cognitive skill, usually developed through exercises, of sustaining metacognitive awareness towards the contents of one's own mind and bodily sensations in the present moment. The term ''mindfulness'' derives from the Pali word ''sati'', a significant element of Buddhist traditions, and the practice is based on '' ānāpānasati'' , Chan, and Tibetan meditation techniques. Since the 1990s, secular mindfullness has gained popularity in the west. Individuals who have contributed to the popularity of secular mindfulness in the modern Western context include Jon Kabat-Zinn and Thích Nhất Hạnh. Clinical psychology and psychiatry since the 1970s have developed a number of therapeutic applications based on mindfulness for helping people experiencing a variety of psychological conditions. Clinical studies have documented both physical- and mental-health benefits of mindfulness in different patient categories as well as in healthy adults and children ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rapid Eye Movement Sleep
Rapid eye movement sleep (REM sleep or REMS) is a unique phase of sleep in mammals (including humans) and birds, characterized by random rapid movement of the eyes, accompanied by low muscle tone throughout the body, and the propensity of the sleeper to dream vividly. The core body and brain temperatures increase during REM sleep and skin temperature decreases to lowest values. The REM phase is also known as paradoxical sleep (PS) and sometimes desynchronized sleep or dreamy sleep, because of physiological similarities to waking states including rapid, low-voltage desynchronized brain waves. Electrical and chemical activity regulating this phase seem to originate in the brain stem, and is characterized most notably by an abundance of the neurotransmitter acetylcholine, combined with a nearly complete absence of monoamine neurotransmitters histamine, serotonin and norepinephrine. Experiences of REM sleep are not transferred to permanent memory due to absence of norepinephrine. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Occipital Lobe
The occipital lobe is one of the four Lobes of the brain, major lobes of the cerebral cortex in the brain of mammals. The name derives from its position at the back of the head, from the Latin , 'behind', and , 'head'. The occipital lobe is the Visual perception, visual processing center of the mammalian brain containing most of the anatomical region of the visual cortex. The primary visual cortex is Brodmann area, Brodmann area 17, commonly called V1 (visual one). Human V1 is located on the Anatomical terms of location#Left and right (lateral), and medial, medial side of the occipital lobe within the calcarine sulcus; the full extent of V1 often continues onto the cerebral hemisphere#Poles, occipital pole. V1 is often also called striate cortex because it can be identified by a large stripe of myelin, the stria of Gennari. Visually driven regions outside V1 are called Extrastriate, extrastriate cortex. There are many extrastriate regions, and these are specialized for different ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hepatic Encephalopathy
Hepatic encephalopathy (HE) is an altered level of consciousness as a result of liver failure. Its onset may be gradual or sudden. Other symptoms may include movement problems, changes in mood, or changes in personality. In the advanced stages, it can result in a coma. Hepatic encephalopathy can occur in those with acute or chronic liver disease. Episodes can be triggered by infections, gastrointestinal bleeding, constipation, electrolyte problems, or certain medications. The underlying mechanism is believed to involve the buildup of ammonia in the blood, a substance that is normally removed by the liver. The diagnosis is typically based on symptoms after ruling out other potential causes. It may be supported by blood ammonia levels, an electroencephalogram, or computer tomography (CT scan) of the brain. Hepatic encephalopathy is possibly reversible with treatment. This typically involves supportive care and addressing the triggers of the event. Lactulose is fre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
