Visual feedback to stabilize head position for fMRI

Thulborn, Keith R.

doi:10.1002/(sici)1522-2594(199905)41:5<1039::aid-mrm24>3.0.co;2-n

Cited by 33 publications

(13 citation statements)

References 21 publications

(26 reference statements)

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“…At each sampling interval, the output from the custom grip device was displayed to the subject using a visual feedback system (Vaillancourt et al, 2003). The feedback was projected using a parallax biofeedback system (Thulborn, 1999) through a mirror located 35 cm from the subject's eyes. The force output was displayed at a refresh rate of 60 Hz and a resolution of 640 × 480 pixels.…”

Section: Methodsmentioning

confidence: 99%

Specific cerebellar regions are related to force amplitude and rate of force development

et al. 2012

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The human cerebellum has been implicated in the control of a wide variety of motor control parameters, such as force amplitude, movement extent, and movement velocity. These parameters often covary in both movement and isometric force production tasks, so it is difficult to resolve whether specific regions of the cerebellum relate to specific parameters. In order to address this issue, the current study used two experiments and SUIT normalization to determine whether BOLD activation in the cerebellum scales with the amplitude or rate of change of isometric force production or both. In the first experiment, subjects produced isometric pinch-grip force over a range of force amplitudes without any constraints on the rate of force development. In the second experiment, subjects varied the rate of force production, but the target force amplitude remained constant. The data demonstrate that BOLD activation in separate sub-areas of cerebellar regions lobule VI and Crus I/II scale with both force amplitude and force rate. In addition, BOLD activation in cerebellar lobule V and vermis VI was specific to force amplitude, whereas BOLD activation in lobule VIIb was specific to force rate. Overall, cerebellar activity related to force amplitude was located superior and medial, whereas activity related to force rate was inferior and lateral. These findings suggest that specific circuitry in the cerebellum may be dedicated to specific motor control parameters such as force amplitude and force rate.

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Section: Methodsmentioning

confidence: 99%

Specific cerebellar regions are related to force amplitude and rate of force development

et al. 2012

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“…Head motion was restricted by placing adjustable padding between the head and the head coil apparatus. A fixation point was given together with visual feedback of the head position to facilitate a stable head position (Thulborn, 1999). BOLD contrast functional images were obtained using a single-shot echo-planar sequence with a repeat time of 2500 ms ( …”

Section: Data Acquisitionmentioning

confidence: 99%

Role of hyperactive cerebellum and motor cortex in Parkinson's disease

et al. 2007

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Previous neuroimaging studies have found hyperactivation in the cerebellum and motor cortex and hypoactivation in the basal ganglia in patients with Parkinson's disease (PD) but the relationship between the two has not been established. This study examined whether cerebellar and motor cortex hyperactivation is a compensatory mechanism for hypoactivation in the basal ganglia or is a pathophysiological response that is related to the signs of the disease. Using a BOLD contrast fMRI paradigm PD patients and healthy controls performed automatic and cognitively controlled thumb pressing movements. Regions of interest analysis quantified the BOLD activation in motor areas, and correlations between the hyperactive and hypoactive regions were performed, along with correlations between the severity of upper limb rigidity and BOLD activation. There were three main findings. First, the putamen, supplementary motor area (SMA) and pre-SMA were hypoactive in PD patients. The left and right cerebellum and the contralateral motor cortex were hyperactive in PD patients. Second, PD patients had a significant negative correlation between the BOLD activation in the ipsilateral cerebellum and the contralateral putamen. The correlation between the putamen and motor cortex was not significant. Third, the BOLD activation in the motor cortex was positively correlated with the severity of upper limb rigidity, but the BOLD activation in the cerebellum was not correlated with rigidity. Further, the activation in the motor cortex was not correlated with upper extremity bradykinesia. These findings provide new evidence supporting the hypothesis that hyperactivation in the ipsilateral cerebellum is a compensatory mechanism for the defective basal ganglia. Our findings also provide the first evidence from neuroimaging that hyperactivation in the contralateral primary motor cortex is not a compensatory response but is directly related to upper limb rigidity.Mailing Address: David E. Vaillancourt, Ph.D. Departments of Movement Sciences University of Illinois at Chicago 808 South Wood Street, 690 CME (MC 994) Chicago, Illinois 60612 Tel: (312) 355-2058 Fax: (312) 355-2305 court1@uic.edu. Publisher's Disclaimer: This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. NIH Public Access Author ManuscriptNeuroimage. Author manuscript; available in PMC 2008 March 1. NIH-PA Author ManuscriptNIH-PA Author Manuscript NIH-PA Author ManuscriptSporadic Parkinson's disease (PD) results from degeneration of the nigrostriatal dopaminergic system leading to resting tremor, rigidity, bradykinesia and akinesia. According to the classic model ...

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“…Head motion was restricted by using adjustable padding between the head and head coil apparatus. In addition, a fixation point was given to the subject together with visual feedback to facilitate a stable head position within and between scans (Thulborn, 1999). Functional images were obtained using a single shot, gradient-echo echo-planar imaging pulse sequence (EPI) (TE 25 ms, TR 2500 ms, flip angle 90°, field of view 200 mm × 200 mm, image matrix 64 × 64, 42 slices at 3 mm thickness with a 0 mm gap in between).…”

Section: Fmri Data Acquisitionmentioning

confidence: 99%

Region of interest template for the human basal ganglia: Comparing EPI and standardized space approaches

Prodoehl

Little

et al. 2008

NeuroImage

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Identifying task related activation in the basal ganglia (BG) is an important area of interest in normal motor systems and cognitive neuroscience. The purpose of this study was to compare changes in brain activation in the BG using results obtained from two different masking methods: a mask drawn in standardized space from a T1 weighted anatomical image and individual region of interest (ROI) masks drawn from each subject's echo-planar (EPI) image from different tasks with reference to the high resolution fast spin echo image of each subject. Two standardized masks were used: a mask developed in Talairach space (Basal Ganglia Human Area Template (BGHAT)) and a mask developed in Montreal Neurological Institute space (MNI mask). Ten subjects produced fingertip force pulses in five separate contraction tasks during fMRI scanning. ROIs were the left caudate, putamen, external and internal portions of the globus pallidus, and subthalamic nucleus. ANOVA revealed a similar average number of voxels in the EPI mask across tasks in each BG region. The percent signal change (PSC) was consistent within each region regardless of which mask was used. Linear regression analyses between PSC in BGHAT and EPI masks and MNI and EPI masks yielded r² values between 0.74-0.99 and 0.70-0.99 across regions, respectively. In conclusion, PSC in different BG ROIs can be compared across studies using these different masking methods. The masking method used does not affect the overall interpretation of results with respect to the effect of task. Use of a mask drawn in standardized space is a valid and time saving method of identifying PSC in the small nuclei of the BG.

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Visual feedback to stabilize head position for fMRI

Cited by 33 publications

References 21 publications

Specific cerebellar regions are related to force amplitude and rate of force development

Specific cerebellar regions are related to force amplitude and rate of force development

Role of hyperactive cerebellum and motor cortex in Parkinson's disease

Region of interest template for the human basal ganglia: Comparing EPI and standardized space approaches

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