brain waves

spontaneous, rhythmic electrical impulses emanating from different areas of the brain. Electroencephalographic brain-wave recordings are used to study sleep stages and cognitive processes. According to their frequencies, brain waves are classified as alpha waves (8–12 Hz), beta waves (13–30 Hz), delta waves (1–3 Hz), gamma waves (31–80 Hz), or theta waves (4–7 Hz). The first substantial account of brain waves was given in 1929 by German neuropsychiatrist Hans Berger (1873–1944).

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Psychology term of the day

November 18th 2024

Labor Management Relations Act

a series of amendments to the National Labor Relations Act that were passed in 1947 to adjust the power balance between unions and employers in the United States, the previous system being regarded as too restrictive of management. The act identified and prohibited certain unfair labor practices of both unions and employers, created the Federal Mediation and Conciliation Service to aid in resolution of disputes, and provided a mechanism for dealing with strikes that create a national emergency. Sponsored by U.S. lawyer and politician Robert Alphonso Taft (1889–1953) and U.S. politician Fred Allan Hartley Jr. (1902–1969), it is also known as the Taft–Hartley Act.