I've written before about the influence of culture and exposure in our ability to assimilate and produce music so I won't go through that again. Suffice to say, if the environment you grew up in treated music with respect and it was a part of your every day life, it's likely you have more of a propensity to create music compared to someone who didn't. What I'm talking about here is something very basic - whether or not the very roots of creating music are part of our genetic make up.
I'm certainly not a psychologist or music therapist or researcher but I believe it is most definitely a part of all of us. It starts with rhythm of course. Our hearts keep a pretty steady beat (hopefully!) and so we "feel" the presence of rhythm every waking moment. The raising and lowering of the pitch, speed and volume of the spoken word is really musical on the most basic level. How we react to those variables teaches us how to listen to music and the emotions and meaning music conveys.
But what about a person's ability to make music? How can we translate those auditory and physical aspects of speech and rhythm into something musical? I believe there are two basic elements in play here. Learning how to listen and replicate, and removing ego issues from the process. A raw beginner has to be conscious of these things and strive to incorporate them in the learning process from moment one.
The best time to do this is when a person is quite young but that doesn't mean someone older is doomed to being "tone deaf" (oh how I hate that term!). It's been my experience that with older students who claim to have "no musical ability" the ego issue is the first thing to conquer. Said it before, and I'll say it again: playing music, especially singing, is a very naked thing. A beginner must be willing to put aside preconceived ideas about what is "good" and what is "bad." This can be difficult if someone close to us is critical. I tell students who mentions slights by spouses or siblings that they should immediately hand their guitar to the critic and say: here, you do it!
And then figure out where they can practice in private!
Assuming a student can put aside ego issues the next step is to learn how to listen and then repeat what they hear. This might involve trying to repeat just a single note or two, either on the guitar or with the voice. That can be daunting and frustrating at first but like any other skill (the best analogy I can think of here is learning a foreign language) you WILL get better at it as time passes. And for goodness sake, don't compare your musical production to someone who's been doing it for a long time. Believe me - at some point they were in exactly the same place you are.
Music is in us. All of us. Some people just have a bit more difficulty letting out. But it's there! If you have any doubts about this, check out the cool little video of the superb singer Bobby McFarrin at a music symposium in 2009.
See what I mean?
Peace & good music,
Gene