Emotional prosody in primary progressive aphasia

Speech often simultaneously communicates propositional and emotional messages. Whereas the propositional message is conveyed by a complex code requiring semantic, lexical, syntactic, and phonemic encoding, the emotional message is often conveyed by prosody, which includes pitch, tempo, and rhythm.1 Broca2 demonstrated in right-handed people that injury to the anterior perisylvian region interferes with the expression of speech. However, Jackson3 observed that even nonfluent aphasic patients could imbue their simple utterances with emotional content by using intonations. He posited that the right hemisphere might be mediating this activity, but this postulate was not tested until Tucker et al.4 demonstrated that patients with right hemisphere damage had impaired ability to express emotional messages by using prosody. Ross and Mesulam5 subsequently described two patients with anterior perisylvian lesions who could not express emotionally intoned speech but could express propositional speech and could comprehend propositional and emotional prosody.

Ghacibeh and Heilman6 recently described a woman with a primary progressive expressive affective aprosodia …