Treatment of adynamia in aphasia

Abstract

Transcortical motor aphasia (TCMA) is an acquired impairment of language expression that occurs following neurologic damage that affects left frontal cortex and spares perisylvian regions. In some individuals with TCMA, verbal expression is rendered nonfluent due to difficulty spontaneously initiating and elaborating upon verbal messages. Nonfluency arises from impaired activation of intended messages and inhibition of competing verbal expressions. This impairment of the intentional aspects of language expression can be termed 'adynamia.' Because adynamic forms of TCMA occur infrequently, few systematic treatment investigations have been reported for this condition. Behavioral treatments have been proposed to engage intact frontal regions to improve the ability to initiate spontaneous verbal expression. Some data suggest that nonsymbolic limb movements performed in the context of speaking activities, a form of what Luria termed gestural reorganization, may improve the adynamic verbal expression. (1) In addition, the influence of pharmacologic treatment with bromocriptine, a dopaminergic agonist, has been considered for its effects on verbal nonfluency in aphasia. Individuals classified as TCMA are more likely to benefit than those with other forms of nonfluent aphasia, suggesting an influence of bromocriptine on circuits necessary to activate spontaneous language. Additional studies are warranted that contrast behavioral and pharmacologic interventions to determine optimal conditions to improve verbal expression in adynamic forms of aphasia.

Drug Therapy of Post-Stroke Aphasia: A Review of Current Evidence

“…Beneficial changes were noted in speech initiation, pauses in conversation, paraphasias, and naming, with these attributed to enhanced dopaminergic tone in the mesocortical pathway (Albert et al 1988). These findings were replicated in other single cases and open-label trials of transcortical motor, adynamic, and Broca's aphasias of moderate severity (Berthier 1999(Berthier , 2005Raymer et al 2001;Raymer 2003), but not in cases with severe Broca's and global aphasias (Gupta and Mlcoch 1992;Sabe et al 1992;Ozeren et al 1995). Moreover, the beneficial effects found in selected single cases and open-label studies were not confirmed in most randomized controlled trials (Gupta et al 1995;Ozeren et al 1995;Sabe et al 1995;Ashtary et al 2006).…”

Afasia transcortical motora: un reporte de caso

“…Solo unas pocas intervenciones de corte conductual han sido propuestas para mejorar la capacidad de iniciar la expresión verbal espontánea, que supone la participación de regiones frontales intactas (22). Algunos datos sugieren que los movimientos no simbólicos concomitantes a la producción oral, como una forma de lo que denomina Luria reorganización gestual, puede mejorar la expresión verbal adinámica.…”

“…También se reporta en la literatura, el efecto del tratamiento farmacológico con bromocriptina, un agonista dopaminérgico, en formas de afasia no fluidas; en particular, los individuos clasificados con ATM tienen más probabilidades de beneficiarse de la farmacoterapia de aquellos que tienen otras formas de afasia no fluente, lo que sugiere una influencia de la bromocriptina en los circuitos necesarios para activar el lenguaje espontáneo (23). No obstante, se señala que las intervenciones farmacológicas en conjunto con las de tipo conductual mejoran la expresión verbal en mayor medida en que lo hace la farmacoterapia cuando se usa como úni-ca opción terapéutica (22). La documentación acerca de la cantidad, proporción y desenlaces de la recuperación de los desórdenes neurocomunicativos, demuestra que es muy difícil predecir a largo plazo la funcionalidad de un paciente con daño cerebral.…”

Pharmacotherapy to Improve the Acquired Aphasia following Brain Damages: A Review Study

“…Among all, bromocriptine agonist of postsynaptic dopamine D2 receptor has been investigated more than others (7,21,23 Ramezani S, et al that the type of aphasia (22,23), the cause of aphasia (98), the treatment plan (99) and dose of medication (100) play a vital role in outcome. Bromocriptine functions on mesocortical dopaminergic neurons which project from mesencephalon to dorsal caudate nucleus of basal gangalia, supplementary motor area (SMA) and anterior cingulum (101).…”

“…Much effort have been put on aphasia pharmacotherapy in past half century particularly revealing conflicting results on dopaminergic agonists. Dopaminergic drugs if taken along with aphasia therapy would be effective in patients with mild to moderate fluent aphasia, though not expected in other conditions (7,(21)(22)(23)(24). The recent two decades has seen accelerated developments in neuroscience research in favor of pharmacotherapy to improve the language deficits (8).…”