Bilaterality in Older and Younger Brains Across a variety of tasks, older adult brains show bilateral activation and young adult brains show unilateral activation. One explanation for this is that older brains compensate for the declining abilities of one neural structure by calling on other neural structures for help (Cabeza, 2002).

ROBERTO CABEZA, CENTER FOR COGNITIVE NEUROSCIENCE, DUKE UNIVERSITY. (A) CABEZA ET AL. (1997); (B) BACKMAN ET AL. (1997).