Word finding deficitsin aphasia: diagnosis and treatment. Rotterdam Aphasia Therapy Study-2 Jong-Hagelstein, M. de 2011-10-28 Doctoral Thesis

Aphasia Imagine finding yourself all of a sudden alone in a Chinese city and not speaking or understanding Chinese. How do you ask for the way or read the signs, buy food and other necessities, watch tv or listen to the news, let alone have a social conversation with someone? This thought experiment might shed some light on how it must be for people to have a stroke and suddenly have lost the ability to communicate. The term aphasia is used to describe an acquired loss or impairment of the language system following brain damage. Damage to the brain can be caused by trauma, a tumor, infection or neurodegenerative disease such as Alzheimer’s disease. But the most frequent cause of aphasia is a stroke, mainly to the left hemisphere, where the language function of the brain is located in nearly all right-handed people and half of the left handers. In the Netherlands, approximately 40,000 people per year experience a stroke.1 About one-third of these patients develop aphasia, with higher frequencies in the early stages after stroke onset. It is estimated that there are about 30,000 people with aphasia in the Netherlands (www.afasie.nl). The severity of aphasia varies from occasional word-finding di≤culties to having no means of communication at all. Individual aphasia profiles also vary regarding the degree of involvement of the modalities of language processing: speaking, comprehension of speech, writing and reading. A central problem for nearly all aphasic people is word finding, which requires intact semantic and phonological processing. During the first year following the stroke event, aphasia tends to improve.2 A recent study found that 74% of patients presenting with aphasia in the hyperacute stage have completely recovered after six months and that aphasia improved in 86% of the patients.3 Most of the recovery occurs in the first three months after which the speed of spontaneous recovery slows, and little additional recovery can be expected after 12 months. Spontaneous recovery of cognitive functions is considered to be associated with the reduction of edema and the reperfusion of previously hypoxic tissue in the perilesional area.4 Neuroplasticity might also underlie some degree of functional recovery after stroke and has been shown to occur in perilesional areas and in areas distant from the lesion in both the acute and chronic phase.5 The most powerful predictor of recovery is initial aphasia severity.6-9 Greater initial stroke severity and lesion volume are associated with greater initial aphasia severity which in turn is associated with poorer outcome. Studies examining other factors including age, sex, handedness and level of education provided conflicting results.
http://repub.eur.nl/res/pub/26766/111028_Jong-Hagelstein%2C%20Marjolein%20de.pdf