Credit assignment in multiple goal embodied visuomotor behavior

The intrinsic complexity of the brain can lead one to set aside issues related to its relationships with the body, but the field of embodied cognition emphasizes that understanding brain function at the system level requires one to address the role of the brain-body interface. It has only recently been appreciated that this interface performs huge amounts of computation that does not have to be repeated by the brain, and thus affords the brain great simplifications in its representations. In effect the brain’s abstract states can refer to coded representations of the world created by the body. But even if the brain can communicate with the world through abstractions, the severe speed limitations in its neural circuitry mean that vast amounts of indexing must be performed during development so that appropriate behavioral responses can be rapidly accessed. One way this could happen would be if the brain used a decomposition whereby behavioral primitives could be quickly accessed and combined. This realization motivates our study of independent sensorimotor task solvers, which we call modules, in directing behavior. The issue we focus on herein is how an embodied agent can learn to calibrate such individual visuomotor modules while pursuing multiple goals. The biologically plausible standard for module programming is that of reinforcement given during exploration of the environment. However this formulation contains a substantial issue when sensorimotor modules are used in combination: The credit for their overall performance must be divided amongst them. We show that this problem can be solved and that diverse task combinations are beneficial in learning and not a complication, as usually assumed. Our simulations show that fast algorithms are available that allot credit correctly and are insensitive to measurement noise

Learning to become an expert : reinforcement learning and the acquisition of perceptual expertise

To elucidate the neural mechanisms underlying the development of perceptual expertise, we recorded ERPs while participants performed a categorization task. We found that as participants learned to discriminate computer-generated "blob'' stimuli, feedback modulated the amplitude of the errorrelated negativity (ERN)-an ERP component thought to reflect error evaluation within medial-frontal cortex. As participants improved at the categorization task, we also observed an increase in amplitude of an ERP component associated with object recognition (the N250). The increase in N250 amplitude preceded an increase in amplitude of an ERN component associated with internal error evaluation (the response ERN). Importantly, these electroencephalographic changes were not observed for participants who failed to improve on the categorization task. Our results suggest that the acquisition of perceptual expertise relies on interactions between the posterior perceptual system and the reinforcement learning system involving medial-frontal cortex

Management of e-learners: some implications for practitioners

Report of a CELT project on supporting students through innovation and researchInformation technologies have played a leading role in supporting many recent changes in teaching and learning approaches in Higher Education. Contemporary innovation finds information technology (IT) at the heart of Higher Education transformation. The opportunities afforded by these learning technologies are well documented in popular academic literature. They point to new applications of the latest communication technologies. However, they also bring with them a host of new questions and challenges. The management of e-learners is likely to be part of a more far-reaching organisational change. Where learning technologies are introduced, a layer of technical complexity is added. The redesign of business processes and structures is far from simple ‘technical’ matter. It involves significant social redesign. The extent to which enabling technology has driven the shift towards learner-centred learning in all educational contexts is a matter of debate. As the century turns, establishing the acceptance, let alone the effectiveness and quality of technology-mediated learning, is still seriously problematic (Salmon, 1999). However, the suitability of information and communication technology (ICT) as a means of encouraging self-directed learning is not in doubt, nor that the role of the tutor is changing to ‘guide on the side’: a facilitator not transmitter, of information (Marchmont, 2000). This paper reports findings of a single case study at Wolverhampton Business School. Qualitative data was collected through structured and unstructured interviews with learners and tutors on Business Administration Award. A total of 20 learners and 5 tutors form the basis of the findings