V. S. Ramachandran, director of the Center for Brain and Cognition at the University of California, San Diego, directed a study that showed that the angular gyrus is at least partially responsible for understanding metaphors. Right-handed patients who had damage to their left angular gyrus and whose speaking and comprehending English was seemingly unaffected, could not grasp the dual nature of metaphor. Given a common metaphorical phrase, each patient could give only a literal meaning. If pressed, they could invent a wild interpretation but it was well off the mark
In another exercise, the patients all failed to be able to describe a bulbous object as "booba" and a jagged object as "kiki," whereas more than 90% of unaffected subjects succeeded in the BoobaKiki.png. This showed an inability to connect visual stimuli to language.
The fact that the angular gyrus is proportionately much larger in hominids than other primates, and its strategic location at the crossroads of areas specialized for processing touch, hearing and vision, leads Ramachandran to believe that it is critical both to conceptual metaphors and to cross-modal abstractions more generally.