Aphasia Neuroplasticity Review

Ohyama et al. (1996)

Reference

AuthorsOhyama M, Senda M, Kitamura S, Ishii K, Mishina M, Terashi A
TitleRole of the nondominant hemisphere and undamaged area during word repetition in poststroke aphasics: a PET activation study
ReferenceStroke 1996; 27: 897-903
PMID8623110
DOI10.1161/01.str.27.5.897

Participants

LanguageJapanese
Inclusion criteriaAble to repeat single words
Number of individuals with aphasia16
Number of control participants6
Were any of the participants included in any previous studies?No
Is age reported for patients and controls, and matched?Yes (mean 56.6 ± 11.8 years, range 38-75 years)
Is sex reported for patients and controls, and matched?Yes (males: 12; females: 4)
Is handedness reported for patients and controls, and matched?Yes (right: 16; left: 0)
Is time post stroke onset reported and appropriate to the study design?No* (moderate limitation) (mean 15.1 ± 16.7 months, range 1.1-50.3 months; a mix of subacute and chronic participants; 8 of each)
To what extent is the nature of aphasia characterized?Comprehensive battery
Language evaluationWAB
Aphasia severityAQ mean 74.3 ± 12.2, range 53.8-92.4
Aphasia type6 anomic, 4 atypical, 4 mild Broca's, 1 mild Wernicke's, 1 transcortical sensory; alternately: 10 fluent, 6 non-fluent
First stroke only?Yes
Stroke typeIschemic only
To what extent is the lesion distribution characterized?Extent and location
Lesion extentMean 33.9 ± 26.3 cc, range 8.1-113.2 cc
Lesion locationL perisylvian
Participants notes

Imaging

ModalityPET (rCBF)
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 (Headtome IV tomograph)
Is the timing of stimulus presentation and image acquisition clearly described and appropriate?Yes
Design typePET
Total images acquired6
Are the imaging acquisition parameters, including coverage, adequately described and appropriate?No (91 mm field of view; coverage limitations not stated)
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?No (lesion impact not addressed)
Imaging notes

Conditions

Are the conditions clearly described?Yes
ConditionResponse typeRepetitionsAll groups could do?All individuals could do?
word repetitionWord (overt)2YesYes
countingMultiple words (overt)2YesYes
restNone2N/AN/A
Conditions notesPatients were able to repeat words well, with phonemic errors on no more than 4 out of 48 words; counting condition not analyzed in this paper

Contrasts

Are the contrasts clearly described?Yes

Contrast 1: word repetition vs rest

Language conditionWord repetition
Control conditionRest
Are the conditions matched for visual demands?Yes
Are the conditions matched for auditory demands?No
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 notes
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 notesBilateral auditory and motor activations are prominent, only slightly L-lateralized
Contrast notes

Analyses

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

ROI analysis 1

First level contrastWord repetition vs 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?Unknown, not reported
Is reaction time matched across the second level contrast?Unknown, not reported
Behavioral data notesSome of the patients made a few errors, so as a group they may have been less accurate than controls
Type of analysisRegions of interest (ROI)
ROI typeFunctional
How many ROIs are there?7
What are the ROI(s)?(1) L posterior inferior frontal; (2) R posterior inferior frontal; (3) L posterior superior temporal; (4) R posterior superior temporal; (5) L rolandic; (6) R rolandic; (7) SMA
How are the ROI(s) defined?Spheres around control peaks
Correction for multiple comparisonsNo correction
Statistical detailsThe rCBF increase in R PIF was also significant at p < 0.005 for nonfluent patients with Fisher's protected least-significant difference
Findings↑ R IFG
↑ R posterior STG/STS/MTG
Findings notes

ROI analysis 2

First level contrastWord repetition vs rest
Analysis classCross-sectional between two groups with aphasia
Group(s)Aphasia fluent (n = 10) vs non-fluent (n = 6)
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?Unknown, not reported
Is reaction time matched across the second level contrast?Unknown, not reported
Behavioral data notes
Type of analysisRegions of interest (ROI)
ROI typeFunctional
How many ROIs are there?7
What are the ROI(s)?(1) L posterior inferior frontal; (2) R posterior inferior frontal; (3) L posterior superior temporal; (4) R posterior superior temporal; (5) L rolandic; (6) R rolandic; (7) SMA
How are the ROI(s) defined?Spheres around control peaks
Correction for multiple comparisonsNo correction
Statistical details
Findings↓ R IFG
Findings notes

ROI analysis 3

First level contrastWord repetition vs rest
Analysis classCross-sectional correlation with language or other measure
Group(s)Aphasia
CovariateSpontaneous speech (WAB)
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?Unknown, not reported
Is reaction time matched across the second level contrast?Unknown, not reported
Behavioral data notes
Type of analysisRegions of interest (ROI)
ROI typeFunctional
How many ROIs are there?7
What are the ROI(s)?(1) L posterior inferior frontal; (2) R posterior inferior frontal; (3) L posterior superior temporal; (4) R posterior superior temporal; (5) L rolandic; (6) R rolandic; (7) SMA
How are the ROI(s) defined?Spheres around control peaks
Correction for multiple comparisonsNo correction
Statistical detailsNo correction for multiple comparisons across WAB subscores
Findings↑ L IFG
Findings notes

ROI analysis 4

First level contrastWord repetition vs rest
Analysis classCross-sectional correlation with language or other measure
Group(s)Aphasia
CovariateComprehension (WAB)
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?Unknown, not reported
Is reaction time matched across the second level contrast?Unknown, not reported
Behavioral data notes
Type of analysisRegions of interest (ROI)
ROI typeFunctional
How many ROIs are there?7
What are the ROI(s)?(1) L posterior inferior frontal; (2) R posterior inferior frontal; (3) L posterior superior temporal; (4) R posterior superior temporal; (5) L rolandic; (6) R rolandic; (7) SMA
How are the ROI(s) defined?Spheres around control peaks
Correction for multiple comparisonsNo correction
Statistical detailsThis non-significant finding is implied but not stated explicitly
FindingsNone
Findings notes

ROI analysis 5

First level contrastWord repetition vs rest
Analysis classCross-sectional correlation with language or other measure
Group(s)Aphasia
CovariateRepetition (WAB)
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?Unknown, not reported
Is reaction time matched across the second level contrast?Unknown, not reported
Behavioral data notes
Type of analysisRegions of interest (ROI)
ROI typeFunctional
How many ROIs are there?7
What are the ROI(s)?(1) L posterior inferior frontal; (2) R posterior inferior frontal; (3) L posterior superior temporal; (4) R posterior superior temporal; (5) L rolandic; (6) R rolandic; (7) SMA
How are the ROI(s) defined?Spheres around control peaks
Correction for multiple comparisonsNo correction
Statistical detailsThis non-significant finding is implied but not stated explicitly
FindingsNone
Findings notes

ROI analysis 6

First level contrastWord repetition vs rest
Analysis classCross-sectional correlation with language or other measure
Group(s)Aphasia
CovariateNaming (WAB)
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?Unknown, not reported
Is reaction time matched across the second level contrast?Unknown, not reported
Behavioral data notes
Type of analysisRegions of interest (ROI)
ROI typeFunctional
How many ROIs are there?7
What are the ROI(s)?(1) L posterior inferior frontal; (2) R posterior inferior frontal; (3) L posterior superior temporal; (4) R posterior superior temporal; (5) L rolandic; (6) R rolandic; (7) SMA
How are the ROI(s) defined?Spheres around control peaks
Correction for multiple comparisonsNo correction
Statistical detailsThis non-significant finding is implied but not stated explicitly
FindingsNone
Findings notes

Notes

Excluded analysesSeparate analyses for fluent and non-fluent patients revealed essentially similar results