Foreign accent syndrome: A multimodal evaluation in the search of neuroscience-driven treatments

Foreign Accent Syndrome Secondary to Medication Withdrawal: A Case Report

“…4,[11][12][13] However, there are currently three reports of FAS associated with right hemisphere lesions, though it has been suggested that these patients have anomalous dominance for language.…”

“…Though this represents a different etiology of FAS than those previously reported in the literature, a recent publication suggests the involvement of dopamine and acetylcholine in the development of FAS. 11 Specifically, it states that the areas of the brain where lesions are often found in FAS are innervated with cholinergic neurons, and that recent studies have shown improvement of communication deficits with donepezil, which increases cholinergic activity through inhibition of acetylcholinesterase. 11 One caveat to these studies is that they were performed in stroke patients, not those with FAS.…”

Editorial: Language beyond Words: The Neuroscience of Accent

“…The increased number of reports on FAS during the past decade (Gurd and Coleman, 2006; Moreno-Torres et al, 2013) have led to a better definition of the three different types of FAS (developmental, psychogenic, and neurogenic; Verhoeven and Mariën, 2010). Several cases describing these subtypes and included in the Research Topic are summarized below.…”

Commentary: Visual Feedback of Tongue Movement for Novel Speech Sound Learning

“…The AIC is one such key circumscribed area susceptible to be voluntarily self-controlled (Ninaus et al, 2013). By acting as a multimodal integration hub, the AIC is in an ideal position for coordinating the activity of several networks devoted to modulate multisensory information (visual, auditory-motor, tactile, somatosensory, Ackermann and Riecker, 2010; Moreno-Torres et al, 2013) involved in feedback of tongue movements during the speech production. In addition, note that healthy subjects activate both AIC during overt speech (Ackermann and Riecker, 2010) and that the AIC together with the left frontal operculum are co-activated during learning foreign sounds (Ventura-Campos et al, 2013).…”

“…Future studies will examine the modulation of neurochemistry with non-invasive brain stimulation (Fiori et al, 2014), drugs (Berthier and Pulvermüller, 2011), or both to ascertain whether the results of novel speech sound learning reported by K & M using visual feedback of tongue movements can be accelerated and maintained in the long-term. Preliminary evidence of the beneficial effect of combining audio-visual feedback training and cholinergic stimulation on reverting FAS has been demonstrated in a single patient (Berthier et al, 2009; Moreno-Torres et al, 2013). Importantly, the almost complete return to native accent in this case of FAS was associated with partial or total normalization of metabolic activity in several regions of the speech production network, especially in the left AIC and ACC (Figure 1).…”