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Introduction:Aphasia persists in about one third of the patients with left hemisphere stroke, yet it is not known if it enhances the risk of dementia, beyond what results from any focal brain lesion. This lack of knowledge is mostly related to the difficulty of cognitive evaluation in people with aphasia. The development of tools aiming to assess cognitive functioning in people with aphasia could overcome this limitation. The aim of this systematic review was to evaluate the frequency and the profile of cognitive impairment in stroke patients with aphasia, to assemble existing non-verbal instruments to be used in patients with language disorders.

Deciding how to manipulate an object to fulfill a goal requires accessing different types of object-related information. How these different types of information are integrated and represented in the brain is still an open question. Here, we focus on examining two types of object-related information–tool-gesture knowledge (i.e., how to manipulate an object), and tool-gesture production (i.e., the actual manipulation of an object). We show a double dissociation between tool-gesture knowledge and tool-gesture production: Patient FP presents problems in pantomiming tool use in the context of a spared ability to perform judgments about an object's manipulation, whereas Patient LS can pantomime tool use, but is impaired at performing manipulation judgments. Moreover, we compared the location of the lesions in FP and LS with those sustained by two classic ideomotor apraxic patients (IMA), using a cortical thickness approach. Patient FP presented lesions in common with our classic IMA that included the left inferior parietal lobule (IPL), and specifically the supramarginal gyrus, the left parietal operculum, the left premotor cortex and the left inferior frontal gyrus, whereas Patient LS and our classic IMA patients presented common lesions in regions of the superior parietal lobule (SPL), motor areas (as primary somatosensory cortex, premotor cortex and primary motor cortex), and frontal areas. Our results show that tool-gesture production and tool-gesture knowledge can be behaviorally and neurally doubly dissociated and put strong constraints on extant theories of action and object recognition and use.