Figure 2d:

Graphs for (a) young and (b) older control groups, (c) patients with PD, and (d) subjects with MCI show representative records of translational and rotational movement measured with a volumetric navigator during an approximately 20-minute 3D MR spectroscopic imaging sequence. Due to selective reacquisition of corrupted data, the measurement was prolonged in the older control (approximately 7 minutes), PD (approximately 2 minutes), and MCI (approximately 4 minutes) groups. Thoracic breathing is more common in older people and causes more head movement than does diaphragmatic breathing, which is more common in young people (17). This is represented by repeated extensive motion, particularly in the X translation, Z translation, and sagittal (Sag) rotation directions. The axes correspond to the following: X = anterior-posterior, Y = left-right, and Z = superior-inferior directions. Cor = coronal, Tra = transverse.