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Purpose Lexical retrieval impairment is a universal characteristic of aphasia and a common treatment focus. Although naming improvement is well documented, there is limited information to shape expectations regarding long-term recovery. This was the motivation for a retrospective study of longitudinal data on the Boston Naming Test (BNT; Kaplan, Goodglass, & Weintraub, 1983, 2000). Method BNT scores were analyzed from a heterogeneous cohort of 42 individuals with anomia associated with a range of aphasia types. The data were collected over the course of 20 years from individuals who had participated in treatment and received at least 2 BNT administrations. A linear mixed model was implemented to evaluate effects of initial BNT score, time postonset, and demographic variables. For those over 55 years of age, BNT change was evaluated relative to data from the Mayo Clinic's Older Americans Normative Studies. Results There was a significant average improvement of +7.67 points on the BNT in individuals followed for an average of 2 years. Overall, the average rate of improvement was +5.84 points per year, in contrast to a decline of 0.23 points per year in a healthy adult cohort from the Mayo Clinic's Older Americans Normative Studies. Naming recovery was approximately linear, with significant main effects of initial BNT score (i.e., initial severity) and time postonset; the greatest changes were noted in those whose initial severity was moderate. Conclusions These findings indicate a positive prognosis for naming improvement over time regardless of demographic factors and provide estimates for clinical predictions for those who seek rehabilitation during the chronic phase.

Anomia is a striking and consistent clinical feature of semantic dementia (SD), a progressive aphasia syndrome associated with focal cortical atrophy of the anterior temporal lobes. Word retrieval deficits in patients with SD have been attributed to the loss of conceptual knowledge, resulting in an impairment referred to as semantic anomia. Whereas an abundance of research has been dedicated to treatment for anomia in individuals with focal brain damage due to stroke, considerably less work has been done regarding treatment for patients with progressive language decline. The purpose of this article is to review the available literature concerning the nature and treatment of anomia in individuals with SD. Several studies have shown that new lexical learning remains possible in these patients. However, newly learned information is likely to be constrained by the learning context, and increased reliance on perceptual and autobiographical contextual information may be necessary to provide critical support for new vocabulary acquisition. There is also evidence suggesting that treatment may slow the progression of anomia over time, even affording some protective benefit to lexical items that are not yet lost. However, treatment efforts are likely to be most beneficial at early stages of the disease, when residual semantic knowledge as well as relatively spared episodic memory may support new learning.

Background: Treatment for lexical retrieval impairment has been shown to yield positive outcomes in individuals with aphasia due to focal lesions, but there has been little research regarding the treatment of such impairments in individuals with progressive aphasia. Aims: The purpose of this study was to examine the therapeutic effects of a semantic treatment for anomia in progressive aphasia relative to the outcome in an individual with stroke-induced aphasia. Methods & Procedures: Two individuals with progressive aphasia and one with aphasia resulting from stroke participated in the study. Each participant presented with fluent, anomic aphasia; however, one of the patients with progressive aphasia demonstrated characteristics indicating a likely progression towards non-fluency. Each participant received a brief, intensive treatment intended to improve lexical retrieval in the context of generative naming for selected semantic categories. Treatment tasks included guided lexical retrieval prompted by the identification and elaboration of items within semantic subcategories, as well as other semantic tasks. Treatment outcomes were quantified using standard effects sizes as well as nonparametric tests comparing pre- versus post-treatment performance. Outcomes & Results: One of the individuals with progressive aphasia showed large treatment effects for lexical retrieval of items from targeted semantic categories. The other progressive aphasia patient showed very small effects overall for treated categories. The individual with the focal lesion due to stroke showed medium-sized effects for trained categories as well as significant improvement on a standardised measure of naming. Conclusions: Findings indicate that intensive, semantically based treatment for lexical retrieval can result in positive outcomes in individuals with progressive as well as stroke-induced aphasia. Examination of individual differences suggests that the status of semantic and episodic memory may provide predictive information regarding responsiveness to treatment. [ABSTRACT FROM AUTHOR]

Background: It has been proposed that anomia following left inferior temporal lobe lesions may have two different underlying mechanisms with distinct neural substrates. Specifically, naming impairment following damage to more posterior regions (BA 37) has been considered to result from a disconnection between preserved semantic knowledge and phonological word forms (pure anomia), whereas anomia following damage to anterior temporal regions (BAs 38, 20/21) has been attributed to the degradation of semantic representations (semantic anomia). However, the integrity of semantic knowledge in patients with pure anomia has not been demonstrated convincingly, nor were lesions in these cases necessarily confined to BA 37. Furthermore, evidence of semantic anomia often comes from individuals with bilateral temporal lobe damage, so it is unclear whether unilateral temporal lobe lesions are sufficient to produce significant semantic impairment. Aims: The main goals of this study were to determine whether anomia following unilateral left inferior temporal lobe damage reflected a loss of semantic knowledge or a post-semantic deficit in lexical retrieval and to identify the neuroanatomical correlates of the naming impairment. Methods & Procedures: Eight individuals who underwent left anterior temporal lobectomy (L ATL) and eight individuals who sustained left posterior cerebral artery strokes (L PCA) completed a battery of language measures that assessed lexical retrieval and semantic processing, and 16 age- and education-matched controls also completed this battery. High-resolution structural brain scans were collected to conduct lesion analyses. Outcomes & Results: Performance of L ATL and L PCA patients was strikingly similar, with both groups demonstrating naming performance ranging from moderately impaired to unimpaired. Anomia in both groups occurred in the context of mild deficits to semantic knowledge, which manifested primarily as greater difficulty in naming living things than nonliving things and greater difficulty in processing visual/perceptual as opposed to functional/associative semantic attributes. Lesion analyses indicated that both patient groups sustained damage to anterior inferior temporal lobe regions implicated in semantic processing. Conclusions: These results contribute to a better understanding of the cognitive mechanism of naming impairment in patients with temporal lobe damage and support the notion that pure anomia and semantic anomia represent two endpoints along a continuum of semantic impairment. Unilateral left temporal lobe lesions in our patients resulted in relatively mild semantic deficits that were apparent primarily in lexical production tasks, whereas severe semantic impairment likely requires bilateral temporal lobe damage. [ABSTRACT FROM AUTHOR]