A neural network model of causative actions

Bridging the Chasm Between Cognitive Representations and Formal Structures of Linguistic Meanings

This paper aims to show that properties of cognitive/conceptual representations and formal-logical structures of linguistic meaning can be inter-translated, recast, transformed into one another, and so united together, even though cognitive/conceptual representations and formal-logical structures of linguistic meaning are apparently distinct in ontology and divergent in their form or character. While cognitive/conceptual representations are ultimately rooted in sensory-motor systems, formal-logical structures of linguistic meaning are abstractions detached from and independent of the actualized world. This paper sketches out the foundations of how representations of linguistic meaning in terms of cognitive/conceptual structures in Cognitive/Conceptual Semantics can be unified with those in terms of formal-logical structures in Formal Semantics. This is done by recasting cognitive/conceptual representations in terms of formal-logical structures of linguistic meaning and re-encoding formal-logical structures of linguistic meaning in terms of cognitive/conceptual representations. Then, these two types of semantic representations, thus shown representationally equivalent, will be related to a series of derivations across levels in neuronal networks and dynamics. The general discussion on unifying cognitive/conceptual representations of linguistic meaning with formal-logical structures is contextualized within the broader context of theorizing in cognitive science.

An action-observation/motor-imagery based approach to differentiate disorders of consciousness: what is beneath the tip of the iceberg?

BACKGROUND

The evaluation of motor imagery in persons with prolonged Disorders of Consciousness (pDOC) is a practical approach to differentiate between patients with Minimally Conscious State (MCS) and Unresponsive Wakefulness Syndrome (UWS) and to identify residual awareness even in individuals with UWS. Investigating the influence of motor observation on motor imagery could be helpful in this regard.

OBJECTIVE

In order to corroborate the clinical diagnosis and identify misdiagnosed individuals, we used EEG recordings, to assess the influence of the low-level perceptual and motoric mechanisms on motor observation on motor imagery, taking into account the role of the high-level cognitive mechanisms in patients with pDOC.

METHODS

We assessed the influence of motor observation of walking in first-person or third-person view (by a video provision) on motor imagery of walking in the first-person view on the visual N190 (expression of motor observation processing), the readiness potential (RP) (expressing motor preparation), and the P3 component (high-level cognitive processes) in a sample of 10 persons with MCS, 10 with UWS, and 10 healthy controls (CG). Specifically, the video showed a first-view or third-view walk down the street while the participants were asked to imagine a first-view walking down the street.

RESULTS

CG showed greater N190 response (low-level sensorimotor processing) in the non-matching than in the matching condition. Conversely, the P3 and RP responses (high-level sensorimotor processing) were greater in the matching than in the non-matching condition. Remarkably, 6 out of 10 patients with MCS showed the preservation of both high- and low-level sensorimotor processing. One UWS patient showed responses similar to those six patients, suggesting a preservation of cognitively-mediated sensorimotor processing despite a detrimental motor preparation process. The remaining patients with MCS did not show diversified EEG responses, suggesting limited cognitive functioning.

CONCLUSIONS

Our study suggests that identifying the low-level visual and high-level motor preparation processes in response to a simple influence of motor observation of motor imagery tasks potentially supports the clinical differential diagnosis of with MCS and UWS. This might help identify UWS patients which were misdiagnosed and who deserve more sophisticated diagnoses.