Aphasia Neuroplasticity Review

Robson et al. (2014)

Reference

AuthorsRobson H, Zahn R, Keidel JL, Binney RJ, Sage K, Lambon Ralph MA
TitleThe anterior temporal lobes support residual comprehension in Wernicke's aphasia
ReferenceBrain 2014; 137: 931-943
PMID24519979
DOI10.1093/brain/awt373

Participants

LanguageUK English
Inclusion criteriaWernicke's aphasia (impaired spoken single word comprehension, impaired single word repetition, fluent, sentence-like speech with phonological/neologistic errors)
Number of individuals with aphasia12
Number of control participants12
Were any of the participants included in any previous studies?No
Is age reported for patients and controls, and matched?Yes (mean 70.1 ± 8.7 years, range 59-87 years)
Is sex reported for patients and controls, and matched?Yes (males: 10; females: 2)
Is handedness reported for patients and controls, and matched?Yes (right: 12; left: 0)
Is time post stroke onset reported and appropriate to the study design?Yes (range 7-84 months)
To what extent is the nature of aphasia characterized?Comprehensive battery
Language evaluationBDAE, PPT, word-to-picture matching test from Cambridge Semantic Battery, single word reading aloud from PALPA
Aphasia severityBDAE comprehension range 6-26 (out of 32); BDAE comprehension scores and percentiles do not seem entirely commensurate
Aphasia typeAll Wernicke's
First stroke only?Yes
Stroke typeMixed etiologies
To what extent is the lesion distribution characterized?Lesion overlay
Lesion extentNot stated
Lesion locationL MCA; all involved STG extending into IPL and temporoparietal junction; 8 extending into MTL; 4 extending into inferior frontal
Participants notes

Imaging

ModalityfMRI
Is the study cross-sectional or longitudinal?Cross-sectional
If longitudinal, at what time point(s) were imaging data acquired?
If longitudinal, was there any intervention between the time points?
Is the scanner described?Yes (Philips Achieva 3 Tesla)
Is the timing of stimulus presentation and image acquisition clearly described and appropriate?No* (moderate limitation) (each condition was acquired in a separate run, which is suboptimal)
Design typeBlock
Total images acquired417
Are the imaging acquisition parameters, including coverage, adequately described and appropriate?Yes (whole brain)
Is preprocessing and intrasubject coregistration adequately described and appropriate?Yes
Is first level model fitting adequately described and appropriate?Yes
Is intersubject normalization adequately described and appropriate?Yes
Imaging notesspin echo fMRI to minimize ATL dropout

Conditions

Are the conditions clearly described?Yes
ConditionResponse typeRepetitionsAll groups could do?All individuals could do?
semantic decision (written word)Button press16YesNo
semantic decision (picture)Button press16YesNo
visual decisionButton press16YesNo
restNone48N/AN/A
Conditions notes

Contrasts

Are the contrasts clearly described?No (see specific limitation(s) below)

Contrast 1: semantic decision (written word and picture) vs visual decision and rest

Language conditionSemantic decision (written word and picture)
Control conditionVisual decision and rest
Are the conditions matched for visual demands?No
Are the conditions matched for auditory demands?Yes
Are the conditions matched for motor demands?No
Are the conditions matched for cognitive/executive demands?No
Is accuracy matched between the language and control tasks for all relevant groups?N/A, tasks not comparable
Is reaction time matched between the language and control tasks for all relevant groups?N/A, tasks not comparable
Behavioral data notesNot comparable because the control condition includes rest
Are control data reported in this paper or another that is referenced?Somewhat
Does the contrast selectively activate plausible relevant language regions in the control group?Somewhat
Are activations lateralized in the control data?No
Control activation notesControl data are provided in Table 6 for contrasts of written word semantic decision vs dual baseline, and picture semantic decision vs dual baseline, but not for the main effect of semantic decision; these data suggest that the contrast activates ventral temporal regions bilaterally
Contrast notesTwo contrasts are described: (1) written word judgment versus a dual baseline of visual judgment and rest; (2) picture judgment versus a dual baseline of visual judgment and rest; these two primary contrasts are reported in patients and controls separately, but no between-group contrasts are reported, so these contrasts are excluded from our review; rather, the between-groups analyses in the paper take the form of ANOVAs; the main effect of group in these ANOVAs collapses across the two described contrasts, therefore we have coded the contrast as the average of the two described contrasts; the exact nature of the computation of dual baseline contrasts is not described

Analyses

Are the analyses clearly described?No* (moderate limitation) (see specific limitation(s) below)

Voxelwise analysis 1

First level contrastSemantic decision (written word and picture) vs visual decision and rest
Analysis classCross-sectional aphasia vs control
Group(s)Aphasia vs control
Covariate
Is the second level contrast valid in terms of the group(s), time point(s), and measures involved?Yes
Is accuracy matched across the second level contrast?No, different
Is reaction time matched across the second level contrast?No, different
Behavioral data notesPatients also less accurate on control condition, but control condition includes rest so coded based on language condition only
Type of analysisVoxelwise
Search volumeWhole brain
Correction for multiple comparisonsClusterwise correction based on arbitrary cluster extent
SoftwareSPM8
Voxelwise p.005
Cluster extent4 voxels (size not stated)
Statistical detailsDual baseline computation not explained
Findings↑ L IFG pars orbitalis
↑ L mid temporal
↑ L anterior temporal
↑ L cerebellum
↑ L hippocampus/MTL
↑ R mid temporal
↑ R anterior temporal
↑ R posterior inferior temporal gyrus/fusiform gyrus
↑ R cerebellum
↑ R hippocampus/MTL
↓ R posterior cingulate
Findings notes

ROI analysis 1

First level contrastSemantic decision (written word and picture) vs visual decision and rest
Analysis classCross-sectional aphasia vs control
Group(s)Aphasia vs control
Covariate
Is the second level contrast valid in terms of the group(s), time point(s), and measures involved?Yes
Is accuracy matched across the second level contrast?No, different
Is reaction time matched across the second level contrast?No, different
Behavioral data notesPatients also less accurate on control condition, but control condition includes rest so coded based on language condition only
Type of analysisRegions of interest (ROI)
ROI typeFunctional
How many ROIs are there?10
What are the ROI(s)?(1) L anterior fusiform gyrus; (2) L temporal pole; (3) L anterior STS; (4) L IFG; (5) L ventral occipito-temporal; (6-10) homotopic counterparts
How are the ROI(s) defined?Spheres around functional peaks from literature
Correction for multiple comparisonsNo correction
Statistical detailsDual baseline computation not explained
Findings↑ L anterior temporal
↑ L posterior inferior temporal gyrus/fusiform gyrus
↑ R posterior inferior temporal gyrus/fusiform gyrus
Findings notes

Notes

Excluded analyses(1) main effect of condition (written words vs pictures); (2) interactions of condition by group (all of which were non-significant); (3) additional analyses were run including only participants who performed above chance, and only correct responses from all participants, but these gave essentially similar results