CBD is similar to PSP, and is thought to affect about half the number of those with PSP.
CBD (Cortico Basal Degeneration) usually starts on one side of the body first, for example, the loss of use of one hand, eventually spreading to the other side. It can cause jerky, awkward movements and a feeling that the limb is no longer part of the body (‘alien' limb). This can make it difficult to do everyday tasks such as cleaning teeth, dressing or combing hair.
In common with PSP, there may be a disturbance of eye movements, although it is less striking than in PSP and problems with upgaze and downgaze are less common.
People living with CBD may have difficulties in problem solving and other behavioural changes, although memory is relatively unaffected. Like PSP, CBD is a very individual disease and the rate of progression of symptoms varies considerably from person to person.
CBD mainly affects people in their 60s and 70s and symptom management has much in common with that recommended for PSP.
PSP and CBD are so closely related that we often refer to them interchangeably (usually as ‘PSP'), and The PSP Association supports both.