Giovanni Buccino

Grasping language - a short story on Embodiment

The new concept of embodied cognition theories has been enthusiastically studied by the cognitive sciences, by as well as such disparate disciplines as philosophy, anthropology, neuroscience, and robotics. Embodiment theory provides the framework for ongoing discussions on the linkage between low cognitive processes as perception and high cognition as language processing and comprehension, respectively. This review gives an overview along the lines of argumentation in the ongoing debate on the embodiment of language and employs an ALE meta-analysis to illustrate and weigh previous findings.The collected evidence on the somatotopic activation of motor areas, abstract and concrete word processing, as well as from reported patient and timing studies emphasizes the important role of sensorimotor areas in language processing and supports the hypothesis that the motor system is activated during language comprehension.

Processing graspable object images and their nouns is impaired in Parkinson's disease patients

According to embodiment, the recruitment of the motor system is necessary to process language material expressing a motor content. Coherently, an impairment of the motor system should affect the capacity to process language items with a motor content. The aim of the present study was to assess the capacity to process graspable objects and their nouns in Parkinsons disease (PD) patients and healthy controls. Participants saw photos and nouns depicting graspable and non-graspable objects. Scrambled images and pseudo-words served as control stimuli. At 150xa0msec after stimulus presentation, they had to respond when the stimulus referred to a real object, and refrain from responding when it was meaningless (go-no go paradigm). In the control group, participants gave slower motor responses for stimuli (both photos and nouns) related to graspable objects as compared to non-graspable ones. This in keeping with data obtained in a previous study with young healthy participants. In the PD group, motor responses were similar for both graspable and non-graspable items. Moreover, error number was significantly greater than in controls. These findings support the notion that when the motor circuits are lesioned, like in PD, patients do not show the typical modulation of motor responses and have troubles in processing graspable objects and their nouns.

The role of the parietal cortex in sensorimotor transformations and action coding

The picture of the human cortical motor system has fully changed in the last two decades. In the light of new data, the notion of a motor system devoted solely to action execution, strictly isolated from the sensory system, is not sustainable. There is evidence that parietal areas are strictly connected to frontal areas and these connections build up sensorimotor circuits aimed at interacting with objects in the environment, and at understanding actions. They are known as the canonic neuron system and mirror neuron system, respectively. These circuits are part of the classic dorsal stream. Recently, the dorsal stream has been further divided into a dorsodorsal and a ventrodorsal stream. The ventrodorsal stream is regarded as functionally linked to object awareness for action recognition/organization. The dorsodorsal stream is proposed to subserve online control of actions. Affordances indicate action possibilities as characterized by object properties the environment provides to interacting organisms. Affordances may be divided into stable and variable ones. According to this distinction, stable affordances emerge from slow offline processing of visual information based on object knowledge as well as previous experiences in object interaction. In contrast, variable affordances emerge from fast online processing of visual information during actual object interaction and refer to changing or temporary object characteristics, such as orientation in space, size changes, including the update of hand shape for grasping, defining overall the current state of the object. It has been proposed that the dorsodorsal stream codes for variable affordances, while the dorsoventral stream codes for stable affordances.