1. Results: Behavioral Performance Area and Laterality of activation
An fMRI Investigation of Sentence Generation Attempts by Chronic Non-fluent Aphasics K.M. McGregor1, K.D. White1, A.B. Moore1 , L. M. Maher2,3, K.K. Peck1, C. E. Wierenga1, K. Gopinath1, M. Kurtzman1, M.Gaeifsky1, A. Wabnitz1, M. Benjamin1, D. A. Soltysik1 , R. Briggs1, B. Crosson1
1Malcom Randall VA RR&D Brain Rehabilitation Research Center and University of Florida, Gainesville, Florida 2Baylor College of Medicine, 3Houston VA Center of Excellence on Healthy Aging with Disabilities This poster is available on the Web at
Background
Methods
Results: Behavioral Performance
fMRI at 3T using a sentence generation task
Pre-scanning task performance assessments on sentence generation
fMRI task: silent sentence generation describing events in simple line drawings
Baseline task: passive viewing of nonsense objects
(e.g.)
Runs: 5 runs with 5 active blocks (26.4 seconds) with a variable baseline interval (17.6 s, 22 s, or 26.4 s). Run order randomized between subjects
fMRI Analysis Procedures:
Individual subject (patients & controls):
Deconvolution (AFNI) with R2 > 0.16 as statistical threshold
Voxel cluster analysis with contiguity threshold of > 100 μL with a 1.8mm voxel radius
Group analysis (controls):
Area under the curve w/ spatial smoothing on 5mm FWHM kernel
t-test: sentence generation against baseline (p<.005);
Voxel cluster analysis with contiguity threshold of > 100 μL
s01
s02
s03
s04
Sentence Generation (% correct)
5.61
16.71
8.54
2.53
Nonword Reading 6
2.14
3.75
Story Telling (Cinderella Task)
Spoken WPM (Normal: 120)
30.6
21.6
29.0
11.7
Number of utterances 15 27 5 3
Mean words per utterance
2.0
4.74
1.6
Percentage of words in sentences
2.4
25.9
0.0
Agrammatism: a disruption in grammatical functions supporting language common in nonfluent aphasia
Neural activation in rehabilitation outcome
Good Outcome
Poor Outcome
Left perilesional areas
Right Frontal
Right perisylvian
Crosson et al., 2005; Wierenga et al., 2006
Naeser et al., 2004;
Vandenbulcke et al., 2005;
Syntactic language generation has received little attention in fMRI particularly with respect to rehabilitiation of nonfluent aphasia
Results: Imaging
GENERATE
VIEW
26.4 s
17.6 s
Participants ID
Gender
Age
TPO (Months)
EDU
WAB AQ
BNT
ANT
S01 F 79 48 12
74.7 32 33
S02 M 61 36 16
68.6 39 49
S03 42 51
57.7 27
S04 74 76 13
58.8 19 22
s01
s02
s01
s02
Control
s03
s04
Red indicates p < 0.005; yellow indicates p<
Area and Laterality of activation
Controls
Area
Patients
Left
Inferior Frontal Gyrus
Right (3 of 4)
Posterior Middle Temporal Gyrus
Right (3 of 4); Bilateral (1of 4)
N/A
Medial Frontal (BA6)
Bilateral (3 of 4)
Conclusions
fMRI Parameters
Gradient Echo EPI; FOV=240mm; TR=1660ms; Matrix 32x64x64 ID
Scanner
Sequence TE
Acquisition plane
Control
3T GE SIGNA
1-shot spiral EPI
18ms
Sagittal
s01
s02
s03
3T Siemens Allegra
Standard EPI
25ms
Axial
s04
Homologues to left lateralized areas implicated in syntactic language production in controls are indicated as active in similar tasks in agrammatic aphasics
Previous findings of right lateralized inferior frontal (Naeser et al., 2004) and posterior perisylvian activation (Vandenbulcke et al., 2005) in patients exhibiting poor performance on language tasks are supported by this investigation
Question: Does the activity in right posterior perisylvian regions and right inferior frontal areas reflect neural processes that are critical or detrimental to rehabilitation of syntactic language production?
Question: Does the left frontal activity outside the inferior frontal gyrus facilitate or interfere with sentence production tasks?
s03
s04
Control: Four healthy adults (Ages: 41, 46, 52, 58)
This research was supported by NIH grants P50-DC03888, R01-DC03455 and the Gainesville Brain Rehabilitation Research & Development Center.