Beta wave, or beta rhythm, is the term used to designate the frequency

Frequency

Frequency is the number of occurrences of a repeating event per unit time. It is also referred to as temporal frequency.The period is the duration of one cycle in a repeating event, so the period is the reciprocal of the frequency...

 range of human brain

Human brain

The human brain has the same general structure as the brains of other mammals, but is over three times larger than the brain of a typical mammal with an equivalent body size. Estimates for the number of neurons in the human brain range from 80 to 120 billion...

 activity between 12 and 30 Hz

Hertz

The hertz is the SI unit of frequency defined as the number of cycles per second of a periodic phenomenon. One of its most common uses is the description of the sine wave, particularly those used in radio and audio applications....

 (12 to 30 transitions or cycles per second). Beta waves are split into three sections: High Beta Waves (19 Hz+); Beta Waves (15–18 Hz); and Low Beta Waves (12–15 Hz). Beta states are the states associated with normal waking consciousness.

Function

Low amplitude beta waves with multiple and varying frequencies are often associated with active, busy, or anxious thinking and active concentration.

Over the motor cortex

Motor cortex

Motor cortex is a term that describes regions of the cerebral cortex involved in the planning, control, and execution of voluntary motor functions.-Anatomy of the motor cortex :The motor cortex can be divided into four main parts:...

 beta waves are associated with the muscle contraction

Muscle contraction

Muscle fiber generates tension through the action of actin and myosin cross-bridge cycling. While under tension, the muscle may lengthen, shorten, or remain the same...

s that happen in isotonic

Isotonic (exercise physiology)

In an isotonic contraction, tension remains unchanged and the muscle's length changes. Lifting an object at a constant speed is an example of isotonic contractions. A near isotonic contraction is known as Auxotonic contraction....

 movements and are suppressed prior to and during movement changes. Bursts of beta activity are associated with a strengthening of sensory feedback in static motor control and reduced when there is movement change. Beta activity is increased when movement
has to be resisted or voluntarily suppressed. The artificial induction of increased beta waves over the motor cortex by a variety of Transcranial magnetic stimulation

Transcranial magnetic stimulation

Transcranial magnetic stimulation is a noninvasive method to cause depolarization or hyperpolarization in the neurons of the brain...

 called Transcranial alternating-current stimulation

Transcranial alternating current stimulation

Transcranial alternating current stimulation is a noninvasive means by which alternating currents applied through the skull over the occipital cortex of the brain entrains in a frequency-specific fashion the neural oscillations of the underlying brain....

 consistent with its link to isotonic contraction produces a slowing of motor movements.

Other brain waves

• Delta wave
  Delta wave
  A delta wave is a high amplitude brain wave with a frequency of oscillation between 0–4 hertz. Delta waves, like other brain waves, are recorded with an electroencephalogram and are usually associated with the deepest stages of sleep , also known as slow-wave sleep , and aid in characterizing the...
  
   – (0.1–4 Hz)
• Theta wave – (4–7 Hz)
• Alpha wave
  Alpha wave
  Alpha waves are neural oscillations in the frequency range of 8–12 Hz arising from synchronous and coherent electrical activity of thalamic pacemaker cells in humans...
  
   – (8–12 Hz)
• Mu wave
  Mu wave
  Mu waves, also known as the comb or wicket rhythm, are electromagnetic oscillations in the frequency range of 8–13 Hz and appear in bursts of at 9 – 11 Hz. Mu wave patterns arise from synchronous and coherent electrical activity of large groups of neurons in the human brain...
  
   – (8–13 Hz)
• Gamma wave
  Gamma wave
  A gamma wave is a pattern of neural oscillation in humans with a frequency between 25 to 100 Hz, though 40 Hz is prototypical.According to a popular theory, gamma waves may be implicated in creating the unity of conscious perception...
  
  – (25–100 Hz)