Computers and machinery 'hum' while they are working and now scientists at Cardiff University's Brain Research Imaging Centre have found that people's brains do too. They found that when people concentrated on a visual pattern their brains oscillated at between 40-70 Hz; equivalent to the lowest range of notes on a piano or the lower notes of a bass guitar. Each person's brain hums at a slightly different note and the frequency of the hum is controlled by the levels of a neurotransmitter called GABA. GABA is an important neurotransmitter and is essential for the normal operation of the brain. Problems with GABA have been associated with epilepsy and schizophrenia and it is hoped that this research may shed light on these conditions.
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