Test-retest precision of functional MR in sensory and motor task activation

• Published in: American journal of neuroradiology : AJNR Vol. 17; no. 1; pp. 95 - 98
• Main Authors: Yetkin, FZ, McAuliffe, TL, Cox, R, Haughton, VM
• Format: Journal Article
• Language: English
• Published: Oak Brook, IL Am Soc Neuroradiology 01.01.1996; American Society of Neuroradiology
• Subjects: Adult; Arousal - physiology; Biological and medical sciences; Brain - blood supply; Brain Mapping - instrumentation; Echo-Planar Imaging - instrumentation; Female; Fingers - innervation; Frontal Lobe - blood supply; Hand - innervation; Humans; Image Processing, Computer-Assisted - instrumentation; Investigative techniques, diagnostic techniques (general aspects); Magnetic Resonance Imaging - instrumentation; Male; Medical sciences; Motor Activity - physiology; Nervous system; Parietal Lobe - blood supply; Radiodiagnosis. Nmr imagery. Nmr spectrometry; Reference Values; Regional Blood Flow - physiology; Reproducibility of Results; Touch - physiology; Performance evaluation; Human; Manual task; Accuracy; Exploration; Functional analysis; Nuclear magnetic resonance imaging; Brain (vertebrata)
• ISSN: 0195-6108; 1936-959X

To determine the test-retest precision of functional MR maps of regions in the brain "activated" by sensory, motor, and cognitive tasks. Echo-planar images were acquired at 1.5 T in four subjects during voluntary motor activity involving the thumb and fingers and during tactile stimulation of the palm. Each subject performed the two tasks twice. Functional images of each task were generated at three thresholds. Test-retest precision was calculated in terms of two ratios: 1) the pixels activated in both iterations of the tasks in proportion to the pixels activated by either iteration of the task, and 2) the ratio modified to include first-order neighboring pixels. The first is referred to as pixel precision, and the latter as first-order-neighbor pixel precision. In each subject, activation from the first and second iteration of each task was located in the same region of the same gyrus. Pixel precision was .57 for the two tasks (at a threshold of 0.50). First-order-neighbor precision was greater than .80 for the two tasks at the same threshold. High test-retest precision can be obtained in functional MR.