Guardian has some unusual insight into the human brain, thanks to a man whose Parkinson’s has left him confined to a wheelchair, but who is still able to ride a bicycle:
This phenomenon is called kinesia paradoxica. While the mechanisms involved are still not understood, the knowledge is invaluable. It may lead to new forms of physical therapy and exercise for people with Parkinson’s disease or other neurological disorders that affect movement, co-ordination or balance.
Currently, the “bicycle sign” is being suggested as an effective and inexpensive way to differentiate between Parkinson’s and the rarer atypical Parkinson’s. One way in which the two diseases differ is in the ability or loss of ability to ride a bicycle.
“Riding a bicycle involves continuous use of all the human’s primary sensory capabilities, visual, vestibular [balance] and proprioceptive [the awareness of one’s body and limb positioning],” says [University of California, Davis, researcher Ron] Hess. “The latter involves sensors in the arms providing information about steering inputs. What is more interesting though is the ability of the trained cyclist to ride a bicycle ‘hands-free’.”