Editing Broca's area (section)

===Speech-associated gestures===
It has been speculated that because speech-associated gestures could possibly reduce lexical or sentential ambiguity, comprehension should improve in the presence of speech-associated gestures. As a result of improved comprehension, the involvement of Broca's area should be reduced.<ref name="pmid17533001" />

Many neuroimaging studies have also shown activation of Broca's area when representing meaningful arm gestures. A recent study has shown evidence that word and gesture are related at the level of translation of particular gesture aspects such as its [[motor goal]] and intention.<ref name="pmid16839281">{{cite journal | vauthors = Gentilucci M, Bernardis P, Crisi G, Dalla Volta R | title = Repetitive transcranial magnetic stimulation of Broca's area affects verbal responses to gesture observation | journal = Journal of Cognitive Neuroscience | volume = 18 | issue = 7 | pages = 1059–74 | date = July 2006 | pmid = 16839281 | doi = 10.1162/jocn.2006.18.7.1059 | s2cid = 18159912 }}</ref> This finding helps explain why, when this area is defective, those who use sign language also have language deficits.<ref name=Carlson>{{cite book |last1=Carlson |first1=N. |year=2013 |chapter=Human Communication |title=Physiology of Behavior |edition=11th |location=Boston |publisher=Allyn and Bacon }}</ref>{{rp|494–7}} This finding, that aspects of gestures are translated in words within Broca's area, also explains language development in terms of evolution. Indeed, many authors have proposed that speech evolved from a primitive communication that arose from gestures.<ref name="pmid18633777"/><ref name="pmid12653308">{{cite journal | vauthors = Lieberman P | title = On the nature and evolution of the neural bases of human language | journal = American Journal of Physical Anthropology | volume = Suppl 35 | pages = 36–62 | year = 2002 | pmid = 12653308 | doi = 10.1002/ajpa.10171 | doi-access = free }}</ref> (See below.)