Therapy-Induced Neuroplasticity in Chronic Aphasia After Phonological Component Analysis: A Matter of Intensity

Abstract

Despite the growing evidence regarding the importance of intensity and dose in aphasia therapy, few well-controlled studies contrasting the effects of intensive and non-intensive treatment have been conducted to date. Phonological components analysis (PCA) treatment for anomia has been associated with improvements in some patients with chronic aphasia; however, the effect of treatment intensity has not yet been studied with PCA. Thus, the aim of the present study was to identify the effect of intensity on neural processing associated with word retrieval abilities after PCA treatment. We used functional magnetic resonance imaging to examine therapy-induced changes in activation during an overt naming task in two patients who suffered from a stroke in the left middle cerebral artery territory. P1 received intensive PCA treatment whereas P2 received the standard, non-intensive, PCA treatment. Behavioral results indicate that both standard and intensive conditions yielded improved naming performance with treated nouns, but the changes were only significant for the patient who received the intensive treatment. The improvements were found to be long lasting as both patients maintained improved naming at 2-months follow-ups. The associated neuroimaging data indicate that the two treatment conditions were associated with different neural activation changes. The patient who received the standard PCA showed significant increase in activation with treatment in the right anterior cingulate, as well as extensive areas in bilateral posterior and lateral cortices. By contrast, the patient who received intensive PCA showed more decreases in activation following the treatment. Unexpectedly, this patient showed subcortical increase in activation, specifically in the right caudate nucleus. We speculate that the recruitment of the caudate nucleus and the anterior cingulate in these patients reflects the need to suppress errors to improve naming. Thus, both short-term intensive and standard, non-intensive, PCA treatment can improve word retrieval in chronic aphasia, but neuroimaging data suggest that improved naming is associated with different neural activation patterns in the two treatment conditions.

Efficacy of a self‐administered treatment using a smart tablet to improve functional vocabulary in post‐stroke aphasia: a case‐series study

“…For example, Leonard et al (2008) investigated the efficacy of the phonological components analysis (PCA) and reported a significant improvement in naming for seven out of 10 participants following this treatment, as well as maintenance of the gains 4 weeks post-treatment and some generalization to untrained items. The efficacy of this treatment was also confirmed in recent studies (e.g., Marcotte et al 2018, Neumann 2018. Most treatments, however, are rarely exclusively semantic or phonological but combine both types of cues (e.g., Raymer and Gonzalez-Rothi 2001).…”

“…The efficacy of this treatment was also confirmed in recent studies (e.g., Marcotte et al . , Neumann ). Most treatments, however, are rarely exclusively semantic or phonological but combine both types of cues (e.g., Raymer and Gonzalez‐Rothi ).…”

A Review on Treatment-Related Brain Changes in Aphasia

“…Three possible options to disentangle the effects of the treatment from practice-related reductions in brain activity (Rapp, Caplan, Edwards, Visch-Brink, & Thompson, 2013) are (a) to compare the fMRI-task of interest with a control task, (b) to compare treated with untreated items, and (c) to estimate the test-retest variability by performing multiple scan sessions pre-and/or posttreatment (Brownsett et al, 2014;Cornelissen et al, 2003;Fridriksson et al, 2007;Fridriksson, 2010;Fridriksson et al, 2006;Fridriksson, Richardson, et al, 2012;Sandberg et al, 2015;Schlaug et al, 2009). However, 11 studies did not perform multiple scan sessions, or mention or use an appropriate control task (such as null events, looking at a fixation cross, or rest; Abel et al, 2014Abel et al, , 2015Jungblut et al, 2014;Marcotte et al, 2018;Menke et al, 2009;Raboyeau et al, 2008;Tabei et al, 2016;Thompson et al, 2010Thompson et al, , 2013Vitali et al, 2007Vitali et al, , 2010, and only one of those 11 contrasted trained items with untrained items to compensate for this (Vitali et al, 2007).…”

“…In addition, across studies, the statistical threshold applied to these contrasts of interest varied. This threshold was sometimes not reported (Marcotte & Ansaldo, 2010;Vitali et al, 2007), and frequently, it was not corrected for multiple comparisons (Abel et al, 2014(Abel et al, , 2015Haldin et al, 2018;Kiran et al, 2015;Marcotte et al, 2013Marcotte et al, , 2018Menke et al, 2009;Thompson, Riley, den Ouden, Meltzer-Asscher, & Lukic, 2013;Vitali et al, 2010;Wan et al, 2014). This again complicates the comparison of response foci across studies.…”

Resting-State Functional Connectivity following Phonological Component Analysis: The Combined Action of Phonology and Visual Orthographic Cues

“…Speech-language therapies developed to improve naming abilities in people with aphasia are numerous. Therapies aiming to reduce anomia are generally based on semantic strategies, such as Semantic Feature Analysis [ 17 , 18 ], or phonological strategies, such as Phonological Component Analysis PCA [ 19 , 20 , 21 , 22 , 23 ]. In phonological therapies, the aim is to facilitate lexical retrieval by increasing the activation of the phonological representation of words [ 24 ].…”