There is no frequency of our thoughts. But there is frequency of our brain waves. There are four types of brain waves. Alpha, beta, theta and delta. Alpha brainwaves are slower, and higher in amplitude. Their frequency ranges from 9 to 14 cycles per second. The frequency of beta waves ranges from 15 to 40 cycles a second. The frequency of theta brain waves , range is normally between 5 and 8 cycles a second. Delta. Here the brainwaves are of the greatest amplitude and slowest frequency. They typically center around a range of 1.5 to 4 cycles per second