This post begins my review of Doidge's references from his book on neuroplasticity.
The first references I have looked through pertain to the work of Michael Merzenich. He has done very interesting research, dating back 4 decades, a lot of it having to do with studying the auditory cortex, and how it changes in response to stimulation of various sorts during different phases of development. Also he done major work researching and developing cochlear implants for treating hearing loss.
His 2006 article about using a "brain plasticity based training program" to improve memory in older adults (http://www.ncbi.nlm.nih.gov/pubmed/16888038) is interesting and encouraging, yet it warrants a close look at the actual results: the memory improvements from this technique were very modest (though significant), also the control groups were both quite passive (one group just looked at DVD videos, the other had no "intervention" at all). It would have been much more interesting to me to see an active control group in which the individuals would be doing simple memory exercises or other active intellectual stimulation for the same length of time. Because this type of active control was absent, the results may aggrandize the specific form of skill training described in the study; this skill training regimen is now being marketed, and money is surely disappearing from the pockets of many people, including many elderly people who may not have an abundant financial reserve. This makes me especially less enthusiastic about the results. I have no doubt that active mental exercise changes the brain through "plasticity" but I have to wonder if we have to sign up for the deal ("save 20% and get free ground shipping!") with this specific technique to achieve this. Perhaps signing up for a book club, memorizing poetry, and playing chess daily, would accomplish similar results. I would like to see what the evidence has to say about this. His website is interesting to look at, has a few mental exercises to check out, the style of which I think really is quite positive and imaginative. I will be curious to see if his approach--and variations of it-- could be specifically helpful in treating disorders such as autism. But I don't see good clinical data out there yet.
As an amateur musician, I have found that "ear training" is probably the most important, but often least taught or practiced, form of mental development for improving musicianship. Merzenich's exercises clearly focus on "ear training" as a significant component. Here's his website for you to check it out yourself: http://bfc.positscience.com/
Here's a link to a program you can acquire, designed for music students, which develops musical ear-training ability much more thoroughly, in my opinion (I recommend this to all musicians): http://www.earmaster.com/