Seeing speech in space and time : psychological and neurological findings.
Ruth Campbell

Wile speechreading – viewing the movements of the speaker’s lower face – cannot deliver all the contrastive information of heard speech, it can certainly help to understand speech in noise or in conditions of impaired hearing. In particular, seeing the speaker can sometimes help to deliver the phonetic features that cannot be heard (e.g. place of articulation, can be seen by lip position and mouth action).

How does the visual system manage this type of task? Studies with brain-lesioned patients can indicate the critical cortical bases for effective speechreading, and studies with normal hearer-viewers confirm and extend these findings. Brain imaging studies offer a newer perspective on these issues.

This talk will address two main questions :

(1) what is the relative importance of resolving visual movement and of resolving visual shape in speechreading?

(2) How does reading speech from faces differ, how resemble, reading other facial actions (such as expression)? The answer indicate just how speechreading might be special.