To investigate the functional connection between numerical cognition and action planning, the authors required participants to perform different grasping responses depending on the parity status of Arabic digits. The results show that precision grip actions were initiated faster in response to small numbers, whereas power grips were initiated faster in response to large numbers. Moreover, analyses of the grasping kinematics reveal an enlarged maximum grip aperture in the presence of large numbers. Reaction time effects remained present when controlling for the number of fingers used while grasping but disappeared when participants pointed to the object. The data indicate a priming of size-related motor features by numerals and support the idea that representations of numbers and actions share common cognitive codes within a generalized magnitude system. Keywords: numerical cognition, action planning, generalized magnitude system, common representation, object graspingIn the last few decades, many authors have emphasized that cognitive representations of perceptual and semantic information can never be fully understood without considering their impact on actions (Gallese & Lakoff, 2005). In this context, interactions between perception and action have been extensively studied (for review, see, e.g., Hommel, Müsseler, Aschersleben, & Prinz, 2001). More recently, researchers also started to focus on the interactions between language and action (e.g., Gentilucci, Benuzzi, Bertolani, Daprati, & Gangitano, 2000;Glenberg & Kaschak, 2002;Lindemann, Stenneken, van Schie, & Bekkering, 2006;Zwaan & Taylor, 2006). However, a cognitive domain that has hardly been investigated in respect to its impact on motor control is the processing of numbers. This is surprising since information about magnitude plays an important role in both cognition and action. Accurate knowledge about size or quantity is required not only for high-level cognitive processes such as number comprehension and arithmetic (Butterworth, 1999; Dehaene, 1997) but also for the planning of grasping movements (Castiello, 2005;Jeannerod, Arbib, Rizzolatti, & Sakata, 1995). Since magnitude processing in mathematical cognition and magnitude processing in motor control have typically been studied independent of each other, little is known about possible interactions between these two cognitive domains.Interestingly, some authors have recently argued that the coding of magnitude information may reflect a direct link between number processing and action planning (Göbel & Rushworth, 2004;Rossetti et al., 2004;Walsh, 2003). This idea is so far primarily based on neuroimaging studies that have found an overlap in activated brain areas during processes related to numerical judgments and those related to manual motor tasks. In particular, the intraparietal sulcus has been suggested to be the locus of an abstract representation of magnitude information (for review, see Dehaene, Molko, Cohen, & Wilson, 2004). At the same time, it is widely agreed that this particular brain r...

In 4 experiments, we investigated the effects of object affordance in reach-to-grasp actions. Participants indicated whether a depicted small or large object was natural or manmade by means of different object-grasping responses (i.e., with a power or a precision grip). We observed that the size of the depicted object affected the grasping kinematics (grip aperture) and the reach-onset times of compatible and incompatible actions. Additional experiments showed that the effect of perceived object size on motor response was modulated by contextual action information and the observation of others' actions with the object. Thus, beyond the observation of object affordance effects in natural grasping actions, this study suggests that the coupling between object perception and action is not static and obligatory. Behavioral effects of action-relevant object features seem rather to depend on contextual action information.

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To investigate the functional connection between numerical cognition and action planning, the authors required participants to perform different grasping responses depending on the parity status of Arabic digits. The results show that precision grip actions were initiated faster in response to small numbers, whereas power grips were initiated faster in response to large numbers. Moreover, analyses of the grasping kinematics reveal an enlarged maximum grip aperture in the presence of large numbers. Reaction time effects remained present when controlling for the number of fingers used while grasping but disappeared when participants pointed to the object. The data indicate a priming of size-related motor features by numerals and support the idea that representations of numbers and actions share common cognitive codes within a generalized magnitude system.

One of the challenges of providing healthcare services is to enhance its value (for patients, staff and the service) by integrating the informal caregivers into the care process, both concretely managing their patient's health conditions and treatment (co-executing) and participating in the whole healthcare process (co-planning). This study aims at exploring the co-production contribution to the healthcare process, analysing whether and how it is related to higher caregivers' satisfaction with service care and reduced staff burnout, in the eyes of the staff. It also investigated two possible factors supporting caregivers in their role of co-producers, namely relationship among staff and informal caregivers related to knowledge sharing (i.e. an ability determinant supporting co-production) and related to role social conflict (i.e. a willingness determinant reducing co-production). Results of a structural equation model on a sample of 119 healthcare providers employed by neurorehabilitation centers in Italy with severe acquired brain injury confirmed that knowledge sharing positively related with caregivers' co-executing and co-planning. Also, social role conflict was negatively related with co-executing but positively with co-planning. Furthermore, co-planning resulted in being unrelated to both outcomes, whereas co-executing was associated with caregivers' satisfaction, as measured by staff perceptions. Overall, our data provided initial empirical evidence supporting the ability of the determinant's contribution in allowing informal caregivers to assume an active role in both co-production domains. Furthermore, as expected, the role of conflict willingness determinant was found to be a hindering factor for co-executing but, conversely, a trigger for co-planning. This result should be considered more carefully in future studies.