Cognitive Representation of Human Action: Theory, Applications, and Perspectives

The Influence of Induced Emotions on Distance and Size Perception and on the Grip Scaling During Grasping

Previous studies have shown that our perception of stimulus properties can be affected by the emotional nature of the stimulus. It is not clear, however, how emotions affect visually-guided actions toward objects. To address this question, we used toy rats, toy squirrels, and wooden blocks to induce negative, positive, and neutral emotions, respectively. Participants were asked to report the perceived distance and the perceived size of a target object resting on top of one of the three emotion-inducing objects; or to grasp the same target object either without visual feedback (open-loop) or with visual feedback (closed-loop) of both the target object and their grasping hand during the execution of grasping. We found that the target object was perceived closer and larger, but was grasped with a smaller grip aperture in the rat condition than in the squirrel and the wooden-block conditions when no visual feedback was available. With visual feedback present, this difference in grip aperture disappeared. These results showed that negative emotion influences both perceived size and grip aperture, but in opposite directions (larger perceived size but smaller grip aperture) and its influence on grip aperture could be corrected by visual feedback, which revealed different effects of emotion to perception and action. Our results have implications on the understanding of the relationship between perception and action in emotional condition, which showed the novel difference from previous theories.

Computational assessment of long-term memory structures from SDA-M related to action sequences

Assistance systems should be able to adapt to individual task-related skills and knowledge. Structural-dimensional analysis of mental representations (SDA-M) is an established method for retrieving human memory structures related to specific activities. For this purpose, SDA-M involves a semi-automatized survey of users (the “split procedure”), which yields data about users’ associations between action representations in long-term memory. Up to now this data about associations has commonly been clustered and visualized by SDA-M software in the form of dendrograms that can be used by human experts as a tool to (manually) assess users’ individual expertise and identify potential issues with respect to predefined action sequences. This article presents new algorithmic approaches for automatizing the process of assessing task-related memory structures based on SDA-M data to predict probable errors in action sequences. This automation enables direct integration into technical systems, e.g. user-adaptive assistance systems. An evaluation study has compared the automatized computational assessments to predictions made by human scholars based on visualizations of SDA-M data. The different algorithms’ outputs matched human experts’ manual assessments in 84% to 86% of the test cases.

The future for PETTLEP: a modern perspective on an effective and established tool

Over the past 15 years there has been much research into the PETTLEP model of motor imagery, originally designed to improve the quality and impact of imagery interventions on sport performance. This article reviews the most recent trends within this research. Despite a suggested change of underpinning mechanisms involved, there is much support for the positive impact of the model when applied within the sporting context and with engaged participants. The model also appears to have provided impact in fields other than sport, such as medicine and music. Therefore we suggest that it has largely met its desired aims. However, not all research has optimised the model's guidelines, with a distinct failure to account for personal relevance when designing imagery scripts or selecting tasks for use in studies. Other recent and pertinent findings relate to the mediating role of expectancy and beneficial augmentation through movement observation. Future research should, however, seek exploitation and clarification towards contemporary issues in motor control, namely; automaticity, the relative merits of internal and external foci and subconscious goal priming. Finally, we endorse the application of imagery, as a conscious intervention, even for execution of unconscious, fast-actions.