The tongue appears to have as many as five articulatory control regions. If this is true, each of these regions of the tongue, or segments, could be independently controlled. What does it mean to be independently controlled? Independent control would be manifested as low correlations between segments, because independent segments could move asynchronously in speech. Previous studies for midline data have supported this and have shown that segments can aggregate or deaggregate dependent on the phonemic content of the speech sample. However, the tongue is a 3D structure, and its muscles are more localized lateral-to-medial than anterior-to-posterior. Therefore, additional lateral units of control are possible [Stone, J. Acoust. Soc. Am. (1990)]. This study looks at correlations between front to back segments of midline points, lateral points, and 3D shape data to determine whether lateral segments need to be considered independently of midline segments. We will also consider what features besides functional independence might cause low correlations for midline or lateral segments.