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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 www.BIRC.phhp.ufl.edu Background Methods 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: 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 Sentence Generation (% correct) Nonword Reading Story Telling (Cinderella Task) –Spoken WPM (Normal: 120) –Number of utterances –Mean words per utterance –Percentage of words in sentences (e.g.) s01 5.61 6 s02 16.71 0 s03 8.54 2.14 s04 2.53 3.75 30.6 15 2.0 2.4 21.6 27 4.74 25.9 29.0 5 1.6 0.0 11.7 3 2.0 0.0 Results: Imaging Participants TPO ID Gender Age (Months) EDU WAB AQ S01 F 79 48 12 74.7 S02 M 61 36 16 68.6 S03 M 42 51 12 57.7 S04 M 74 76 13 58.8 BNT ANT 32 33 39 49 27 27 19 22 VIEW GENERATE VIEW 17.6 s 26.4 s 26.4 s s01 s02 s03 s04 •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): s01 •Deconvolution (AFNI) with R2 > 0.16 as statistical threshold •Voxel cluster analysis with contiguity threshold of > 100 μL with a 1.8mm voxel radius Control •Group analysis (controls): s02 •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 s03 s04 •Control: Four healthy adults (Ages: 41, 46, 52, 58) fMRI Parameters Gradient Echo EPI; FOV=240mm; TR=1660ms; Matrix 32x64x64 Acquisition ID Scanner Sequence TE plane Control s01 3T GE 1-shot 18 s02 SIGNA spiral EPI ms Sagittal 3T s03 Siemens Standard 25 s04 Allegra EPI ms Axial Red indicates p < 0.005; yellow indicates p< 0.001. Area and Laterality of activation Controls Area Patients Left Left Inferior Frontal Gyrus Posterior Middle Temporal Gyrus Right (3 of 4) Right (3 of 4); Bilateral (1of 4) N/A Medial Frontal (BA6) Bilateral (3 of 4) Conclusions •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? This research was supported by NIH grants P50-DC03888, R01-DC03455 and the Gainesville Brain Rehabilitation Research & Development Center.