Normal EEG Activity

The cerebral activity recorded at electroencephalography is generally rhythmic, that is, it consists of regularly recurring waveforms of similar duration and morphology. It is widely believed that the rhythmicity is imposed on the cerebral cortex by a thalamic pacemaker. '4

Activity recorded in the human EEG is characterized by its frequency. In normal adults, a posteriorly predominant 8- to 12-Hz rhythm is present and is attenuated by eye opening; this is designated the alpha rhythm (...Fig 2,4.-1.). Faster-frequency activity, or beta activity, is also present to a variable extent, has a generalized distribution, and is enhanced by certain medications such as benzodiazepines. Activity slower than 8 Hz is designated as theta (4 to 7 Hz) or delta (less than 4 Hz) activity. Such slow activity is a normal feature of certain stages of sleep but is generally not present in awake alert adults.

Free Yourself from Panic Attacks

Free Yourself from Panic Attacks

With all the stresses and strains of modern living, panic attacks are become a common problem for many people. Panic attacks occur when the pressure we are living under starts to creep up and overwhelm us. Often it's a result of running on the treadmill of life and forgetting to watch the signs and symptoms of the effects of excessive stress on our bodies. Thankfully panic attacks are very treatable. Often it is just a matter of learning to recognize the symptoms and learn simple but effective techniques that help you release yourself from the crippling effects a panic attack can bring.

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