Correspondence effect driven by salient visual asymmetries in integral object stimuli.

The handle-to-hand correspondence effect consists of faster and more accurate responses when the responding hand is aligned with the handle side of an object tool, compared to when they lay on opposite sides. This effect has been attributed to the activation of affordances. Recent studies, however, claimed that it may depend on the spatial coding of the object on the basis of its visual asymmetry (location-coding account). Affordances are namely direct and meaningful relations between recognized objects and the observers' action system. Therefore, any manipulation that disrupts the body structure of object tools could potentially affect their identification and prevent the activation of affordances. The present study investigated the nature of the handle-to-hand correspondence effects by manipulating structural asymmetry and visual salience of object tools, while preserving their integrity that is, leaving unaltered the original possibilities to activate grasping affordances. Three experiments were run. Results were consistent with the location-coding account and claim for accurate control of visual asymmetries in object stimuli during investigation of affordance effects.

Action and object words are differentially anchored in the sensory motor system - A perspective on cognitive embodiment.

Embodied and grounded cognition theories have assumed that the sensorimotor system is causally involved in processing motor-related language content. Although a causal proof on a single-cell basis is ethically not possible today, the present fMRI study provides confirmation of this longstanding speculation, as far as it is possible with recent methods, employing a new computational approach. More specifically, we were looking for common activation of nouns and objects, and actions and verbs, representing the canonical and mirror neuron system, respectively. Using multivariate pattern analysis, a resulting linear classifier indeed successfully generalized from distinguishing actions from objects in pictures to distinguishing the respective verbs from nouns in written words. Further, these action-related pattern responses were detailed by recently introduced predictive pattern decomposition into the constituent activity atoms and their relative contributions. The findings support the concept of canonical neurons and mirror neurons implementing embodied processes with separate roles in distinguishing objects from actions, and nouns from verbs, respectively. This example of neuronal recycling processing algorithms is consistent with a multimodal brain signature of human action and object concepts. Embodied language theory is thus merged with actual neurobiological implementation.

The role of finger representations and saccades for number processing: an FMRI study in children.

A possible functional role of finger representations for the development of early numerical cognition has been the subject of recent debate; however, until now, only behavioral studies have directly supported this view. Working from recent models of number processing, we focused on the neural networks involved in numerical tasks and their relationship to the areas underlying finger representations and saccades in children aged 6-12 years. We were able to differentiate three parietal circuits that were related to distinct aspects of number processing. Abstract magnitude processing was subserved by an association area also activated by saccades and visually guided finger movements. Addition processes led to activation in an area only engaged during saccade encoding, whereas counting processes resulted in the activation of an area only activated during visually guided finger movements, namely in the anterior intraparietal sulcus. Apart from this area, a large network of specifically finger-related brain areas including the ventral precentral sulcus, supplementary motor area, dorso-lateral prefrontal cortex, insula, thalamus, midbrain, and cerebellum was activated during (particularly non-symbolic) exact addition but not during magnitude comparison. Moreover, a finger-related activation cluster in the right ventral precentral sulcus was only present during non-symbolic addition and magnitude comparison, but not during symbolic number processing tasks. We conclude that finger counting may critically mediate the step from non-symbolic to symbolic and exact number processing via somatosensory integration processes and therefore represents an important example of embodied cognition.