Brain Wave Frequencies
Shown above are the frequencies most commonly used to identify different types of electrical activity in the brain. The top row is “raw” EEG which is a mixture of slower, intermediate and faster frequencies. Above, in descending order, are the frequencies of Delta (.5 to 4 cycles per second); Theta (4 to 8 cycles per second; Alpha (8 to 12 cycles per second and ; Beta 13 to 24 cycles per second. Above these frequencies are higher Beta and Gamma ranges which are not shown. In the case of Attention Deficit Disorder, There is usually an excessive amount of the slower frequencies relative to faster ones. This can mean that the brain has a harder time shifting into Beta activity, which is associated with working harder and getting into focus.