Is STM involved in sentence comprehension?

We discuss the literature concerning the role of auditory-verbal short-term memory (phonological loop) in sentence comprehension. We critically analyze data concerning patients with a selective deficit of the phonological loop, then we examine aphasic patients with deficit of auditory-verbal short-term memory and we consider the effect of STM treatment on sentence comprehension. Finally, results from imaging and TMS studies are discussed. In our opinion, data from the literature suggest that both components of the phonological loop are involved in the comprehension of some type of sentence, namely syntactically complex sentences that load on memory, such as center-embedded object relative clauses. However, it is crucial to investigate further patients with a selective STM impairment or aphasic patients, by using extensive and sophisticated experimental material.