Resonator Resonator A resonator is a device or system that exhibits resonance or resonant behavior, that is, it naturally oscillates at some frequencies, called its resonant frequencies, with greater amplitude than at others. The oscillations in a resonator can be either electromagnetic or mechanical (including acoustic). Resonators are used to either generate waves of specific frequencies or to select specific frequencies from a signal. Musical instruments use acoustic resonators that produce sound waves of specific tones. Another example is quartz crystals used in electronic devices such as radio transmitters and quartz watches to produce oscillations of very precise frequency. A cavity
Large irregular activity EEG, the non-rhythmic pattern of large irregular activity,(LIA). LIA has the predominant pattern of large amplitude slow waves that contain some fluctuations of sharp spikes (sharp waves) of 50–100 ms duration. The predominant frequency of LIA is slower than that of theta waves. LIA is often accompanied by ripples in the pyramidal cell layer. When the neural circuitry of the hippocampus is activated it tends to oscillate at theta frequencies. It has also been noted that a fair proportion of hippocampal neurons fire in a correlation with sharp wave activity. The theta state is thought to be involved in the