The linkage of hand and body gestures in conjunction with speech is further revealed by the nature of gesture use in blind individuals during conversation. This phenomenon uncovers a function of gesture that goes beyond portraying communicative content of language and extends David McNeill's view of the gesture-speech system. This suggests that gesture and speech work tightly together, and a disruption of one (speech or gesture) will cause a problem in the other. Studies have found strong evidence that speech and gesture are innately linked in the brain and work in an efficiently wired and choreographed system. McNeill's view of this linkage in the brain is just one of three currently up for debate; the others declaring gesture to be a "support system" of spoken language or a physical mechanism for lexical retrieval.