Doctorat en sciences psychologiques / info:eu-repo/semantics/nonPublished

This thesis focuses on the problem of "autonomous agents". It is assumed that such agents want to be in a desired state which can be assessed by the agent itself when it observes the consequences of its own actions. Therefore the feedback from the motor output via the environment to the sensor input is an essential component of such a system. As a consequence an agent is defined in this thesis as a self-referential system which operates within a closed sensor- mot or-sensor feedback loop. The generic situation is that the agent is always prone to unpredictable disturbances which arrive from the outside, i.e. from its environment. These disturbances cause a deviation from the desired state (for example the organism is attacked unexpectedly or the temperature in the environment changes, ...). The simplest mechanism for managing such disturbances in an organism is to employ a reflex loop which essentially establishes reactive behaviour. Reflex loops are directly related to closed loop feedback controllers. Thus, they are robust and they do not need a built-in model of the control situation. However, reflexes have one main disadvantage, namely that they always occur 'too late'; i.e., only after a (for example, unpleasant) reflex eliciting sensor event has occurred. This defines an objective problem for the organism. This thesis provides a solution to this problem which is called Isotropic Sequence Order (ISO-) learning. The problem is solved by correlating the primary reflex and a predictive sensor input: the result is that the system learns the temporal relation between the primary reflex and the earlier sensor input and creates a new predictive reflex. This (new) predictive reflex does not have the disadvantage of the primary reflex, namely of always being too late. As a consequence the agent is able to maintain its desired input-state all the time. In terms of engineering this means that ISO learning solves the inverse controller problem for the reflex, which is mathematically proven in this thesis. Summarising, this means that the organism starts as a reactive system and learning turns the system into a pro-active system. It will be demonstrated by a real robot experiment that ISO learning can successfully learn to solve the classical obstacle avoidance task without external intervention (like rewards). In this experiment the robot has to correlate a reflex (retraction after collision) with signals of range finders (turn before the collision). After successful learning the robot generates a turning reaction before it bumps into an obstacle. Additionally it will be shown that the learning goal of 'reflex avoidance' can also, paradoxically, be used to solve an attraction task.

Across three experiments, we assessed how location and color information contributes to the identification of an object whose image has been degraded, making its identity ambiguous. In Experiment 1, some of the target objects had fixed locations within the scene. We found that subjects used this location information during search and later to identify the blurred target objects. In Experiment 2, we tested whether location and color information can be combined to identify degraded objects, and results were inconclusive. In Experiment 3, both the location and color of each object was variable but statistically predictive of the object's identity. We found that subjects used both sources of information-color and location - equally when identifying the blurred image of the object. Overall, these findings suggest that location information may be as determining as intrinsic feature information to identify objects when the objects' intrinsic features are degraded. / by Derrick Schlangen. / Thesis (M.A.)--Florida Atlantic University, 2013. / Includes bibliography. / Mode of access: World Wide Web. / System requirements: Adobe Reader.

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Is it possible to learn without awareness? If so, what can learn without awareness, and what are the different mechanisms that differentiate between learning with and without consciousness? How can best measure awareness? Here are a few of the many questions that I have attempted to investigate during the past few years. The main goal of this thesis was to explore the differences between conscious and unconscious learning. Thus, I will expose the behavioral and computational explorations that we conducted during the last few years. To present them properly, I first review the main concepts that, for almost a century now, researchers in the fields of neuroscience have formulated in order to tackle the issues of both learning and consciousness. Then I detail different hypotheses that guided our empirical and computational explorations. Notably, a few series of experiments allowed identification of several mechanisms that participate in either unconscious or conscious learning. In addition we explored a computational framework for explaining how one could learn unconsciously and nonetheless gain subjective access to one’s mental events. After reviewing the unfolding of our investigation, I detail the mechanisms that we identified as responsible for differences between learning with and without consciousness, and propose new hypotheses to be evaluated in the future.

Recent studies show that when words are correlated with the colours they are printed in (e.g., MOVE is presented 75% of the time in blue), colour identification is faster when the word is presented in its expected colour (MOVE in blue) than in an unexpected colour (MOVE in green). The present series of experiments explored the possible mechanisms involved in this colour-word contingency learning effect. Experiment 1 demonstrated that the effect was already present after 18 learning trials. During subsequent unlearning, the effect extinguished equally rapidly, suggesting that only a handful of the most recently encountered trials are used to predict responses. Two reanalyses of data from Schmidt, Crump, Cheesman, and Besner (2007) ruled out an account of the effect in terms of stimulus repetitions. Experiments 2 and 3 demonstrated that participants who carry a memory load do not show a contingency effect, supporting the hypothesis that limited-capacity resources are used to retrieve a small number of trial memories in order to prepare a response. Experiment 4 demonstrated that memory resources are required for both storage and retrieval processes.

This work is based on qualitative interviews with four educationists who before their university studies lack education in their own field of work. The study aims to explore how higher learning influenced and affected these people. As a theoretical point of view the concept of implicit learning and Aristotle’s epistemological approach was used. The study gives an idea that the concept of knowledge is advanced and can go from practical experience to more theoretical understandings. The result of the study shows, despite some criticism on the standard of the education, that the subjects proved to have developed understanding in reflection, communication and personal awareness. In addition this kind of comprehension can be hidden from us and therefore difficult to understand and explain.

Recent studies show that when words are correlated with the colours they are printed in (e.g., MOVE is presented 75% of the time in blue), colour identification is faster when the word is presented in its expected colour (MOVE in blue) than in an unexpected colour (MOVE in green). The present series of experiments explored the possible mechanisms involved in this colour-word contingency learning effect. Experiment 1 demonstrated that the effect was already present after 18 learning trials. During subsequent unlearning, the effect extinguished equally rapidly, suggesting that only a handful of the most recently encountered trials are used to predict responses. Two reanalyses of data from Schmidt, Crump, Cheesman, and Besner (2007) ruled out an account of the effect in terms of stimulus repetitions. Experiments 2 and 3 demonstrated that participants who carry a memory load do not show a contingency effect, supporting the hypothesis that limited-capacity resources are used to retrieve a small number of trial memories in order to prepare a response. Experiment 4 demonstrated that memory resources are required for both storage and retrieval processes.

Under typical between stimulus dual-task conditions, implicit sequence learning typically suffers, except under within stimulus conditions, where the stimuli for both tasks are the same. This finding is inconclusive, given that it has not been replicated and the study under which it was obtained was methodologically flawed. The finding also seemed to contradict the psychological refractory period finding that simultaneous presentation of the two task stimuli will result in performance decrements. Two experiments were conducted to test the effect of within stimulus presentation in a dual-task implicit learning task. In Experiment 1, within stimulus presentation resulted in improved sequence learning, relative to between stimulus presentation. The second experiment did not show an effect of response selection load under within stimulus presentation conditions. The findings suggest that implicit learning can occur under attentionally demanding conditions, but that the incidental task structure to be learned should be comprised of stimuli that are already attended during primary task processing.

Thesis (M. Sc.) -- University of Alberta, 2010. / "A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Master of Science, Psychology, University of Alberta." Title from pdf file main screen (viewed on January 5, 2010). Includes bibliographical references.