Evolutionary autonomous agents and the nature of apraxia

BACKGROUND: Evolutionary autonomous agents are robots or robot simulations whose controller is a dynamical neural network and whose evolution occurs autonomously under the guidance of a fitness function without the detailed or explicit direction of an external programmer. They are embodied agents with a simple neural network controller and as such they provide the optimal forum by which sensorimotor interactions in a specified environment can be studied without the computational assumptions inherent in standard neuroscience. METHODS: Evolutionary autonomous agents were evolved that were able to perform identical movements under two different contexts, one which represented an automatic movement and one which had a symbolic context. In an attempt to model the automatic-voluntary dissociation frequently seen in ideomotor apraxia, lesions were introduced into the neural network controllers resulting in a behavioral dissociation with loss of the ability to perform the movement which had a symbolic context and preservation of the simpler, automatic movement. RESULTS: Analysis of the changes in the hierarchical organization of the networks in the apractic EAAs demonstrated consistent changes in the network dynamics across all agents with loss of longer duration time scales in the network dynamics. CONCLUSION: The concepts of determinate motor programs and perceptual representations that are implicit in the present day understanding of ideomotor apraxia are assumptions inherent in the computational understanding of brain function. The strength of the present study using EAAs to model one aspect of ideomotor apraxia is the absence of these assumptions and a grounding of all sensorimotor interactions in an embodied, autonomous agent. The consistency of the hierarchical changes in the network dynamics across all apractic agents demonstrates that this technique is tenable and will be a valuable adjunct to a computational formalism in the understanding of the physical basis of neurological disorders

Getting the point: tracing worked examples enhances learning

Embodied cognition perspectives suggest that pointing and tracing with the index finger may support learning, with basic laboratory research indicating such gestures have considerable effects on information processing in working memory. The present thesis examined whether tracing worked examples could enhance learning through decreased intrinsic cognitive load. In Experiment 1, 56 Year 6 students (mean age = 11.20, SD = .44) were presented with either tracing or no-tracing instructions on parallel lines relationships. The tracing group solved more acquisition phase practice questions and made fewer test phase errors, but otherwise test results were limited by ceiling effects. 42 Year 5 students (mean age = 10.50, SD = .51) were recruited in Experiment 2 to better align the materials with students’ knowledge levels. The tracing group outperformed the non-tracing group at the test and reported lower levels of test difficulty, interpreted as lower levels of intrinsic cognitive load. Experiment 3 recruited 52 Year 6 and Year 7 students (mean age = 12.04, SD = .59) presented with materials on angle relationships of a triangle; the tracing effect was replicated on test scores and errors, but not test difficulty. Experiment 4 used the parallel lines materials to test hypothesized gradients across experimental conditions with 72 Year 5 students (mean age = 9.94, SD = .33), predicting the tracing on the paper group would outperform the tracing above the paper group, who in turn would outperform the non-tracing group. The hypothesized gradient was established across practice questions correctly answered, practice question errors, test questions correctly answered, test question time to solution, and test difficulty self-reports. The results establish that incorporating the haptic input into worked example-based instruction design enhances the worked example effect and that tracing worked examples is a natural, simple yet effective way to enhance novices’ mathematics learning

Being mathematical : an exploration of epistemological implications of embodied cognition

In this thesis I explore epistemological implications of embodied cognition in the hope of developing my apprehension of what it means to think mathematically. I allow my understanding of embodied cognition to emerge in stages, early in the piece laying contrasts against which it may be set, infolding elements to the purpose of qualitatively interpreting data as my thesis finds form. I use the language of autopoiesis to frame an understanding of change in the context of an individual’s learning and also within broader constructs, such as in mathematics classrooms. I recognise dualisms and set them aside in an attempt to reread what it means to think mathematically.Research from a variety of fields constitutes one part of my data, the second part being a selection of experiences drawn from mathematics classes I have taught. In balancing the two, I find that an embodied account contributes a means of interpreting mathematical experience wherein received boundaries, such as between you and me, and categories, such as "number", are not globally robust, and intentionality pervades and shapes the worlds we create.The perspective that embodiment affords my apprehension of mathematical thinking is consistent with a formulation in which judgements of what is good are aligned in part with a kind of aesthetic, whereby being moral is founded in innate dispositions. The question of what one is to do with an embodied epistemology is therefore focused on a consideration of how I am to orient myself to teaching mathematics.Throughout all of this, the locus of my attention remains within the classroom, fixed upon the goal of eliciting perspective and on developing skill in interpreting experience; on becoming a tactful teacher, sensitive to the tacit language of the body

Plan and Situated Action as a Function of Activity Category

Plans do not serve the particular circumstances of a given situation, but rather serve as abstract descriptions of some future activities. The relationship between plans, which are abstract, and actions, which are concrete, is referred to as the relationship between plans and situated actions. This relationship can be formulated in the following questions: 1) How do individuals conceive of future activities? 2) How does an individual who is acting upon a plan adjust when facing contingencies? The relationship between plans and situated actions has remained a source of intense academic discussions (e.g., Bardram, 1997; Bardram & Hensen, 2010; Leudar & Costall, 1996; Ng, 2002; Schmidt, 1997; Suchman, 1987). Despite the ample research on the relationship between plans and situated actions, a review of the literature indicates that the problem has not been adequately addressed (Randall et al., 2007; Suchman 2003), which has compelled this researcher to create a theoretical model that integrates the disparate nature of plans and line of actions. Drawing on research on cognition and categorization theory, this thesis proposes a theoretical framework that conceptualizes the relationship between plans and situated actions in terms of activity categories. Specifically, the theoretical framework draws on the prototype and basic-level category theories of categorization, both of which were developed primarily by Rosch (1978), as well as the field theory developed by Lewin (1936). Categorization theories are used to address plans’ abstractness as they capture typifications of human experience. Field theory is used to address the concreteness of action as it captures dynamic properties of the situation in the here and now. The basic premise of the theoretical framework is that individuals conceive (have a knowledge) of plans and their attributes as future activity categories with a range of possibilities. These possibilities are structurally graded, ranging from highly typical to atypical. Plans are believed to be formed based on what is typical for the activity. The theoretical framework argues that an association exists between an individual’s knowledge of typical adjustment relevant to the activity and actual adjustment the individual makes while performing the activity. With this in mind, the theoretical framework considers the actor’s perspective to be central to the investigation. Based on the theoretical framework, several hypotheses are formularized and tested. An in-depth case study conducted in a ready-mix concrete company was used to examine aspects of the theoretical framework empirically. The results of the case study provide a wide range of independent evidence supporting the framework. In addition, an experimental methodology was developed for quantitative testing in the laboratory aspects of the theoretical framework not attainable in the case study. Theoretical and practical implications of the proposed framework and empirical findings are examined. Future research directions are discussed