Computational and Robotic Models of Early Language Development: A Review

We review computational and robotics models of early language learning and development. We first explain why and how these models are used to understand better how children learn language. We argue that they provide concrete theories of language learning as a complex dynamic system, complementing traditional methods in psychology and linguistics. We review different modeling formalisms, grounded in techniques from machine learning and artificial intelligence such as Bayesian and neural network approaches. We then discuss their role in understanding several key mechanisms of language development: cross-situational statistical learning, embodiment, situated social interaction, intrinsically motivated learning, and cultural evolution. We conclude by discussing future challenges for research, including modeling of large-scale empirical data about language acquisition in real-world environments. Keywords: Early language learning, Computational and robotic models, machine learning, development, embodiment, social interaction, intrinsic motivation, self-organization, dynamical systems, complexity.Comment: to appear in International Handbook on Language Development, ed. J. Horst and J. von Koss Torkildsen, Routledg

The Search for Invariance: Repeated Positive Testing Serves the Goals of Causal Learning

Positive testing is characteristic of exploratory behavior, yet it seems to be at odds with the aim of information seeking. After all, repeated demonstrations of one’s current hypothesis often produce the same evidence and fail to distinguish it from potential alternatives. Research on the development of scientific reasoning and adult rule learning have both documented and attempted to explain this behavior. The current chapter reviews this prior work and introduces a novel theoretical account—the Search for Invariance (SI) hypothesis—which suggests that producing multiple positive examples serves the goals of causal learning. This hypothesis draws on the interventionist framework of causal reasoning, which suggests that causal learners are concerned with the invariance of candidate hypotheses. In a probabilistic and interdependent causal world, our primary goal is to determine whether, and in what contexts, our causal hypotheses provide accurate foundations for inference and intervention—not to disconfirm their alternatives. By recognizing the central role of invariance in causal learning, the phenomenon of positive testing may be reinterpreted as a rational information-seeking strategy

Self-directedness, integration and higher cognition

In this paper I discuss connections between self-directedness, integration and higher cognition. I present a model of self-directedness as a basis for approaching higher cognition from a situated cognition perspective. According to this model increases in sensorimotor complexity create pressure for integrative higher order control and learning processes for acquiring information about the context in which action occurs. This generates complex articulated abstractive information processing, which forms the major basis for higher cognition. I present evidence that indicates that the same integrative characteristics found in lower cognitive process such as motor adaptation are present in a range of higher cognitive process, including conceptual learning. This account helps explain situated cognition phenomena in humans because the integrative processes by which the brain adapts to control interaction are relatively agnostic concerning the source of the structure participating in the process. Thus, from the perspective of the motor control system using a tool is not fundamentally different to simply controlling an arm

Discovering Affordances Through Perception and Manipulation

International audienceConsidering perception as an observation process only is the very reason for which robotic perception methods are to date unable to provide a general capacity of scene understanding. Related work in neuroscience has shown that there is a strong relationship between perception and action. We believe that considering perception in relation to action requires to interpret the scene in terms of the agent's own potential capabilities. In this paper, we propose a Bayesian approach for learning sensorimotor representations through the interaction between action and observation capabilities. We represent the notion of affordance as a probabilistic relation between three elements: objects, actions and effects. Experiments for affordances discovery were performed on a real robotic platform in an unsupervised way assuming a limited set of innate capabilities. Results show dependency relations that connect the three elements in a common frame: affordances. The increasing number of interactions and observations results in a Bayesian network that captures the relationships between them. The learned representation can be used for prediction tasks

Single image 3D human pose estimation from noisy observations

Markerless 3D human pose detection from a single image is a severely underconstrained problem because different 3D poses can have similar image projections. In order to handle this ambiguity, current approaches rely on prior shape models that can only be correctly adjusted if 2D image features are accurately detected. Unfortunately, although current 2D part detector algorithms have shown promising results, they are not yet accurate enough to guarantee a complete disambiguation of the 3D inferred shape. In this paper, we introduce a novel approach for estimating 3D human pose even when observations are noisy. We propose a stochastic sampling strategy to propagate the noise from the image plane to the shape space. This provides a set of ambiguous 3D shapes, which are virtually undistinguishable from their image projections. Disambiguation is then achieved by imposing kinematic constraints that guarantee the resulting pose resembles a 3D human shape. We validate the method on a variety of situations in which state-of-the-art 2D detectors yield either inaccurate estimations or partly miss some of the body parts.Preprin

Inference to the best prediction : a reply to Wanja Wiese

Responding to Wanja Wiese’s incisive commentary, I first develop the analogy between predictive processing and scientific discovery. Active inference in the Bayesian brain turns out to be well characterized by abduction (inference to the best explanation), rather than by deduction or induction. Furthermore, the emphasis on control highlighted by cybernetics suggests that active inference can be a process of “inference to the best prediction”, leading to a distinction between “epistemic” and “instrumental” active inference. Secondly, on the relationship between perceptual presence and objecthood, I recognize a distinction between the “world revealing” presence of phenomenological objecthood, and the experience of “absence of presence” or “phenomenal unreality”. Here I propose that world-revealing presence (objecthood) depends on counterfactually rich predictive models that are necessarily hierarchically deep, whereas phenomenal unreality arises when active inference fails to unmix causes “in the world” from those that depend on the perceiver. Finally, I return to control-oriented active inference in the setting of interoception, where cybernetics and predictive processing are most closely connected

From Biological to Synthetic Neurorobotics Approaches to Understanding the Structure Essential to Consciousness (Part 3)

This third paper locates the synthetic neurorobotics research reviewed in the second paper in terms of themes introduced in the first paper. It begins with biological non-reductionism as understood by Searle. It emphasizes the role of synthetic neurorobotics studies in accessing the dynamic structure essential to consciousness with a focus on system criticality and self, develops a distinction between simulated and formal consciousness based on this emphasis, reviews Tani and colleagues' work in light of this distinction, and ends by forecasting the increasing importance of synthetic neurorobotics studies for cognitive science and philosophy of mind going forward, finally in regards to most- and myth-consciousness

Mastering Overdetection and Underdetection in Learner-Answer Processing: Simple Techniques for Analysis and Diagnosis.

International audienceThis paper presents a "didactic triangulation" strategy to cope with the problem of reliability of NLP applications for Computer Assisted Language Learning (CALL) systems. It is based on the implementation of basic but well mastered NLP techniques, and put the emphasis on an adapted gearing between computable linguistic clues and didactic features of the evaluated activities. We claim that a correct balance between noise (i.e. false error detection) - and silence (i.e. undetected errors) is not only an outcome of NLP techniques, but of an appropriate didactic integration of what NLP can do well - and what it cannot do. Based on this approach, ExoGen is a prototype for generating activities such as gapfill exercises. It integrates a module for error detection and description, which checks learners' answers against expected ones. Through the analysis of graphic, orthographic and morphosyntactic differences, it is able to diagnose problems like spelling errors, lexical mix-ups, errors prone agreement, conjugation errors, etc. The first evaluation of ExoGen outputs, based on the FRIDA learner corpus, has yielded very promising results, paving the way for the development of an efficient and general model adapted to a wide variety of activities