Understanding EEG & brainwave frequencies

Electroencephalographic biofeedback. Electroencephalographic(EEG) biofeedback involves the measurement of brainwave activity. EEG activity is recorded at the scalp and can be broken down into numerous bandwidths based on frequency components. The most frequently used bandwidth in biofeedback investigations appearstobethealphabandwidth(8-12 Hz)(Petr

Severalstudies(Crews,Martin,Hart,&Piparo, 1991;Hatfieldetal,, 1984;Landers et al., 1991;Salazar, Landers, Petruzzello, Han, Crews, & Kubitz, 1990)have used left- hemisphere biofeedback training in precision sports like archery, shooting, and golf. These studies suggest that biofeedback training can improve athlete performance, but usually w

EEG biofeedback could affect athletic performance, specifically in target sports such as shooting, archery, and golf. For example, Hatfield, Landers, and Ray (1984) reported that as shooters prepare to shoot, there is a marked shift from left to right hemispheric activation. Crews (1991) found that for golf performance, the greater left-to-right he

Forexample,theathlete may hear a tone, the presence of which indicates the Occurrence of EEG alpha ac- tivity of 20 pV or greater. He may recognize that whenever this tone appears, he coincidentally experiences a relaxed, “idling” mental state where he is not thinking a b o u t a n y t h i n g i n p a r t i c u l a r . By s u s t a i n i n g t h i

EEG feedback is an instrumental learning process whose end result is the facilita- tion of voluntary control of EEG activity. This procedure involves the use of exter- nal EEG monitoring devices especially designed to convey to the individual ongoing informationconcerningtheelectricalactivityofhisherbrain.

The EEG appears to contain four major frequency bands: beta (above 13 Hz), alpha (8-13 Hz), theta (4-7 Hz), and delta (0.5-3.5 Hz). An EEG is not useful for determining specific brain functions, but for discerning more general states of arousal, which are identified as: delta: deep sleep; theta: periods of dreaming: alpha: relaxed awareness; beta:

The number of EEG cycles occurring within a given time interval is called its frequency and is measured in hertz (Hz) or cycles per second (GPS). The greater the number of cycles per second, the higher the frequency

The human brain produces a continuous output of minute electrical signals. The

magnitude of these signals is so small that it is measured in microvolts (FV), or millionths of a volt. However, the signals can be accurately detected and recorded. To do this, the signals must first be picked up by electrodes attached to the surface of the scalp and the

The electroencephalogram, or EEG, is a complex bioelectric signal that reflects the functional status of large pools of cortical neurons and their modulation by subcorti- cal regulatory influences