Hearing music: The auditory cortex (1) is organized in terms of sound frequencies, with some cells responding to low frequencies and others to high. Moving from the inside to the outside of part of the cortex, different kinds of analysis are taking place. In the core, basic musical elements, such as pitch and volume, are analyzed, whereas surrounding regions process more complex elements, such as timbre, melody and rhythm.

Imagining music: Singing Twinkle, Twinkle Little Star in your head stimulates the auditory cortex even though you are not actually hearing the tune. The activity, however, occurs in small, discrete areas (1), and to a lesser magnitude. The inferior frontal gyrus (2) tends to be associated with retrieving memories and is thus stimulated as you recall: "how I wonder what you are." Scientists believe the dorsolateral frontal cortex (3) is responsible for holding the song in working memory while it is being imagined.

Playing music: There are few activities that require more of the brain than playing music. It uses complex feedback systems that take in information, such as pitch and melody, through the auditory cortex (1), and allow the performer to adjust his playing. The visual cortex (2) is activated by reading — or even imagining — a score; the parietal lobe (3) is involved in a number of processes, including computation of finger position; the motor cortex (4) helps control body movements; the sensory cortex (5) is stimulated with each touch of the instrument; the premotor area (6) remains somewhat mysterious but somehow helps perform movements in the correct order and time; the frontal lobe (7) plans and coordinates the overall activity; and the cerebellum (8) helps create smooth, integrated movements.

Reacting emotionally to music: When you gets the "chills" from a piece of music, the "reward" structures in your inner brain (cross section), such as the ventral tegmental area (1), are stimulated. These are the same areas that are activated when a hungry person eats, when an aroused person has sex, or when a drug addict snorts cocaine. If you are listening to a song you find pleasant, activity in the amygdala (2) is inhibited. This is the part of the brain that is typically associated with negative emotion, such as fear.

Plastic perception: Don’t drop the music program just yet! Research shows musical training in children enhances the activity of important neural systems. Changes are in regions of the brain that relate to playing an instrument, such as the auditory cortex (LEFT, TOP 1), used for processing musical tones; the motor cortex (LEFT, TOP 2), a region activated when using the hands or fingers; the cerebellum (LEFT, TOP 3), a part of the brain used in timing and learning; and the corpus callosum (LEFT, BOTTOM CROSS SECTION 4), which acts as a bridge between both hemispheres of the brain. Other regions may also be enhanced, but this doesn’t necessarily mean that the enhanced neural activity will extend to other abilities.

It is also thought that musicians who have had early training use their brains differently than non-musicians. For example, musicians use more complex circuitry in both sides of the brain compared to non-musicians. Some scientists believe musicians also tend to use the left half of their brain when analyzing music. The left hemisphere processes language and is used for reasoning tasks, leading scientists to believe musicians process musical information more analytically than those without training. It was commonly thought that people experienced the majority of music-related activities in the right hemisphere, where emotional and spatial information are processed. Today, however, it is believed that both hemispheres network together when it comes to musical activity.

For these kinds of brain changes to occur, musical training must take place early on in a musician’s life. If it doesn’t occur until after puberty, there isn’t as much modification. Brain enhancements are also specific to instrument types. When a violin player, for example, listens to a violin tune, the activity in his or her auditory cortex is quite high. But when the same violinist listens to a trumpet tune, the activity in the auditory cortex is relatively small.

Absolute pitch/tone deafness: Music may very well be a part of everyone’s life, but not everyone feels part of music. Tone deafness is a hereditary condition where people are incapable of telling the difference between musical notes, known as amusia (becoming tone-deaf after birth) or congenital amusia (born with tone-deafness). People who are tone deaf have no trouble speaking or understanding speech or making sense of everyday sounds, but they can’t recognize pitch, which is essential to music perception. Scientists are unsure what part of the brain is responsible for the activity.

While many people suffer from tone deafness, perfect pitch, found at the other end of the tonal scale, is not as common. Beethoven and Mozart are both believed to have had absolute pitch. Perfect pitch, or absolute pitch, which occurs when a person can recognize or sing a note as easily as they can tell the difference between blue and yellow, without the aid of a reference. Scientists have found that the dorsolateral prefrontal cortex (1), which is used in the gaining of skill and memory retrieval, and the auditory cortex (2) work together to produce absolute pitch. It is a combination of genetics and environment that produce the talent. Studies have shown that musical training must take place before age 15 for perfect pitch to develop.

Take this simple test to see if you have absolute pitch (select 'misc' then 'absolute pitch test')!

Musical hallucinations: Imagine hearing a tune in your head as if a 12-piece orchestra is playing it in the room next door. But there is no orchestra. There’s not even a radio or CD player blasting out the tune. The song is in your mind, and you can’t make it stop.

Nick Warner, a psychiatrist in southwest England, says there is a solid difference between imagining a tune — otherwise known as having a song stuck in your head — and having a musical hallucination. A song in your head, he says, is something you have a lot of control over and you are aware that the song isn’t actually playing. With a musical hallucination, however, music plays in your mind that can’t be consciously stopped, and the sound is so real that you think it is actually playing somewhere nearby.

Since musical hallucinations have not yet been thoroughly studied, it is difficult to map out sections of the brain that are activated when someone experiences them. It is thought that the brain map may be similar to that of imagining music, but there is no concrete evidence.

When it comes to the brain, a musical hallucination has the same qualities as hearing music, but lacks the same stimulus. Dr. Tim Griffiths, a neurologist at the University of Newcastle Upon Tyne in England, suggests the hallucinations occur because the music-processing regions in the brain are looking for signals to interpret. The brain could be producing occasional random impulses that the regions still interpret as sound, even though no sound is coming from the ears.

There is no cure for musical hallucinations, since researchers aren’t sure of the cause. But fighting fire with fire has worked – some patients can turn on a radio or start a conversation which interrupts the musical hallucination, giving them some peace. Warner says to improve someone’s hearing and reduce the amount of social isolation may also work. Finally, he has found that anti-psychotic medication in low doses can also be effective. But none of these methods works completely. Warner says it’s a fairly rare occurrence that requires more study.

The beat goes on and on and on...
Musical hallucinations occur in about 1 in every 10,000 people, according to Warner and his colleague Victor Aziz, have looked at what people tend to hear during their hallucinations. Their study, involving 30 referrals from older people with musical hallucinations, found these songs to be the most common:

• Abide with me (6 people)
• Silent Night (2 people)
• Away in a Manger (2 people)
• The Old Rugged Cross (2 people)
• Hark the Herald Angels Sing (2 people)
• Good King Wenceslas
• Jingle Bells
• Love Divine
• O Come all ye Faithful
• How Great Thou art
• On the Cross, Where I Found the Lord
• Cwm Rhondda
• Onward Christian Soldiers
• The Welsh National anthem
• The American National Anthem
• I Love You
• Three Blind Mice
• Show me the Way to go Home
• How much is that Doggy in the Window
• Yes We have no Bananas
• When I'm Cleaning Windows
• Stars and Stripes
• The Red Flag
• Roll out the Barrel