Christian Balkenius

• PhD
• Professor (Full) at Lund University

Humans are expert percievers of behavioural properties, including the timing of movements. Even short hesitancies and delays can be salient depending on the context. This article presents results from a pilot study on time delays in a human-robot interaction setting using the Wizard of Oz paradigm. Participants (n=17) played Tic-Tac-Toe with the hu...

Perception is not a passive process but the result of an interaction between an organism and the environment. This is especially clear in haptic perception that depends entirely on tactile exploration of an object. We investigate this idea in a system-level brain model of somatosensory and motor cortex and show how it can use signals from a humanoi...

What can artificial intelligence learn from the cognitive sciences? We review some fundamental aspects of how human cognition works and relate it to different brain structures and their function. A central theme is that cognition is very different from how it is envisioned in classical artificial intelligence which offers a novel path toward intell...

In contrast to artificial systems, animals must forage for food. In biology, the availability of energy is typically both precarious and highly variable. Most importantly, the very structure of organisms is dependent on the continuous metabolism of nutrients into ATP, and its use in maintaining homeostasis. This means that energy is at the centre o...

We present data from two online human-robot interaction experiments where 227 participants viewed videos of a humanoid robot exhibiting faulty or non-faulty behaviours while either remaining mute or speaking. The participants were asked to evaluate their perception of the robot's trustworthiness, as well as its likeability, animacy, and perceived i...

The aim of this position paper is to propose a reflection on how to account for and investigate the many ways in which interaction between robots and humans requires co-ordination, negotiation or reformulation of meanings emerging in the ongoing interaction. Towards this aim, we argue, a perspective shift may be needed: to frame interactions as soc...

Life-likeness is a property that can be used both to deceive people that a robot is more intelligent than it is or to facilitate the natural communication with humans. Over the years, different criteria have guided the design of intelligent systems, ranging from attempts to produce human-like language to trying to make a robot look like an actual h...

Organisms must cope with different risk/reward landscapes in their ecological niche. Hence, species have evolved behavior and cognitive processes to optimally balance approach and avoidance. Navigation through space, including taking detours, appears also to be an essential element of consciousness. Such processes allow organisms to negotiate preda...

Reinforcement learning systems usually assume that a value function is defined over all states (or state-action pairs) that can immediately give the value of a particular state or action. These values are used by a selection mechanism to decide which action to take. In contrast, when humans and animals make decisions, they collect evidence for diff...

We tested whether the observation of motor action encoding social motor intention would cause the spontaneous processing of a complementary response when performed by a humanoid robot. We designed the robot’s arm and upper body movements to manifest the kinematic profiles of human individual and social motor intention and designed a simple task tha...

Ikaros is an open framework for system-level brain modeling and real-time robot control. Version 2 of the system includes a range of computational components that implements various algorithms and methods ranging from models of neural circuits to control systems and hardware interfaces for robot. Ikaros supports the design and implementation of lar...

Epi is a humanoid robot developed by Lund University Cognitive Science Robotics Group. It was designed to be used in experiments in developmental robotics and has proportions to give a childlike impression while still being decidedly robotic. The robot head has two degrees of freedom in the neck and each eye can independently move laterally. There...

Mutually adaptive interaction involves the robot as a partner as opposed to a tool, and requires that the robot is susceptible to similar environmental cues and behavior patterns as humans are. Recognition, or the acknowledgement of the other as individual, is fundamental to mutually adaptive interaction between humans. We discuss what recognition...

The current study examined the role of visually perceived material properties in motor planning, where we analyzed the temporal and spatial components of motor movements during a seated reaching task. We recorded hand movements of 14 participants in three dimensions while they lifted and transported paper cups that differed in weight and glossiness...

Connectionist architectures constitute a popular method for modelling animal associative learning processes in order to glean insights into the formation of cognitive capacities. Such approaches (based on purely feedforward activity) are considered limited in their ability to capture relational cognitive capacities. Pavlovian learning value-based m...

Autonomous machines are in the near future likely to increasingly interact with humans, and carry out their functions outside controlled settings. Both of these developments increase the requirements of machines to be trustworthy to humans. In this work, we argue that machines may also benefit from being able to explicitly build or withdraw trust w...

The project “A Plurality of Lives” was funded and hosted by the Pufendorf Institute for Advanced Studies at Lund University, Sweden. The aim of the project was to better understand how a second origin of life, either in the form of a discovery of extraterrestrial life, life developed in a laboratory, or machines equipped with abilities previously o...

In this paper we show how learning can be used to implement a system for attention. We use a simple pre-attentive system that implements pre-attentive maps of simple low-level descriptors. The goal of the attention system is to learn appropriate attention mechanisms so that one efficiently finds relevant cues in the scene. In the paper we test how...

We show how a multi-resolution network can model the development of acuity and coarse-to-fine processing in the mammalian visual cortex. The network adapts to input statistics in an unsupervised manner, and learns a coarse-to-fine representation by using cumulative inhibition of nodes within a network layer. We show that a system of such layers can...

We introduce a memory model for robots that can account for many aspects of an inner world, ranging from object permanence, episodic memory, and planning to imagination and reveries. It is modeled after neurophysiological data and includes parts of the cerebral cortex together with models of arousal systems that are relevant for consciousness. The...

The partial reinforcement extinction effect (PREE) is an experimentally established phenomenon: behavioural response to a given stimulus is more persistent when previously inconsistently rewarded than when consistently rewarded. This phenomenon is, however, controversial in animal/human learning theory. Contradictory findings exist regarding when t...

We explore to what degree movement together with facial features in a humanoid robot, such as eyes and mouth, can be used to convey mental states. Several animation variants were iteratively tested in a series of experiments to reach a set of five expressive states that can be reliably expressed by the robot. These expressions combine biologically...

This paper presents initial attempts to combine a humanoid robot with the teachable agent approach. Several design choices are discussed, including the decision to use a robot instead of a virtual agent and which behaviours to implement in the robot. A pilot study explored how the interaction with a robot seemed to influence children’s engagement a...

We present a system-level connectionist model of pupil control that includes brain regions believed to influence the size of the pupil. It includes parts of the sympathetic and parasympathetic nervous system together with the hypothalamus, amygdala, locus coeruleus, and cerebellum. Computer simulations show that the model is able to reproduce a num...

Spaces in the brain can refer either to psychological spaces, which are derived from similarity judgments, or to neurocognitive spaces, which are based on the activities of neural structures. We want to show how psychological spaces naturally emerge from the underlying neural spaces by dimension reductions that preserve similarity structures and th...

We propose that moral behaviour of artificial agents could (and should) be intrinsically grounded in their own sensory-motor experiences. Such an ability depends critically on seven types of competencies. First, intrinsic morality should be grounded in the internal values of the robot arising from its physiology and embodiment. Second, the moral pr...

We argue that social robots should be designed to behave similarly to humans, and furthermore that social norms constitute the core of human interaction. Whether robots can be designed to behave in human-like ways turns on whether they can be designed to organize and coordinate their behavior with others' social expectations. We suggest that social...

Background The magnitude of multimodal enhancement in the brain is believed to depend on the stimulus intensity and timing. Such an effect has been found in many species, but has not been previously investigated in insects. ResultsWe investigated the responses to multimodal stimuli consisting of an odour and a colour in the antennal lobe and mushro...

The Builder Robot is a complete mobile robotics platform and includes an arm with a gripper and an active vision system. This report describes the steps to put together the robot from 3D printed files. Instructions are also included on how to assemble the electronic systems of the robot. The intention is that it should be possible to build the robo...

We investigate four different methods for background estimation in calcium imaging of the insect brain and evaluate their performance on six data sets consisting of data recorded from two sites in two species of moths. The calcium fluorescence decay curve outside the potential response is estimated using either a low-pass filter or constant, linear...

Significance Where people look generally reflects and reveals their moment-by-moment thought processes. This study introduces an experimental method whereby participants’ eye gaze is monitored and information about their gaze is used to change the timing of their decisions. Answers to difficult moral questions such as “Is murder justifiable?” can b...

One contribution of 18 to a Theme Issue 'The principles of goal-directed decision-making: from neural mechanisms to computation and robotics'. The why, what, where, when and how of goal-directed choice: neuronal and computational principles The central problems that goal-directed animals must solve are: 'What do I need and Why, Where and When can t...

A novel model of role of conditioning in attention is presented and evaluated on a Nao humanoid robot. The model implements conditioning and habituation in interaction with a dynamic neural field where different stimuli compete for activation. The model can be seen as a demonstration of how stimulus-selection and action-selection can be combined an...

A current aim in research on moral cognition is the development of computational models of moral choices and judgements. We fit diffusion models with and without dependence on visual fixations to data on binary moral choices. We find that a fixation dependent model provides a better fit and can capture many features of the empirical data. We discus...

Speech is usually assumed to start with a clearly defined preverbal message, which provides a benchmark for self-monitoring and a robust sense of agency for one's utterances. However, an alternative hypothesis states that speakers often have no detailed preview of what they are about to say, and that they instead use auditory feedback to infer the...

What would it be like if we said one thing, and heard ourselves saying something else? Would we notice something was wrong? Or would we believe we said the thing we heard? Is feedback of our own speech only used to detect errors, or does it also help to specify the meaning of what we say? Comparator models of self-monitoring favor the first alterna...

In this work, we present a biologically inspired model for recognition of occluded patterns. The general architecture of the model is based on the two visual information processing pathways of the human visual system, i.e. the ventral and the dorsal pathways. The proposed hierarchically structured model consists of three parallel processing channel...

This paper proposes a cognitive architecture based on Kahneman's dual process theory [1]. The long-term memory is modeled as a transparent neural network that develops autonomously by interacting with the environment. The working memory is modeled as a buffer containing nodes of the long-term memory. Computations are defined as processes in which w...

We present the transparent neural networks, a graph-based computational model that was designed with the aim of facilitating human understanding. We also give an algorithm for developing such networks automatically by interacting with the environment. This is done by adding and removing structures for spatial and temporal memory. Thus we automatica...

Purpose: This study explores the possibilities of transferring peripheral tactile stimulations from an artificial hand to the forearm skin. Method: A tactile display applied to the forearm skin was used to transfer tactile input to the forearm from various locations on a hand displayed on a computer screen. Discernment of location, levels of pre...

We present experiments with a multimodal system based on a novel variant of the Self-Organizing Map (SOM) called the Associative Self-Organizing Map (A-SOM). The A-SOM is similar to the SOM and develops a representation of its input space, but also learns to associate its activity with additional inputs, e.g. the activities of one or several extern...

We present a bimodal model able to internally simulate expected sequences of perceptions within a modality likely to follow the last sensory experience. Simultaneously reasonable perceptual expectations are elicited in the other modality. Our model is based on the novel associative self-organizing map (A-SOM), which develops a representation of the...

Naïve hawkmoths (Manduca sexta) learn from a single trial to approach and attempt to feed from an artificial flower of an innately unpreferred green colour even when a distractor flower with a preferred yellow colour is present. In some of the animals, the choice of the innately unpreferred colour during free-flight testing persists for several day...

We present two models of the behaviour of the hawkmoth Manduca sexta when it approaches an artificial flower with an olfactory, visual or multimodal cue. The first model treats each condition separately while the second model combines both types of sensory cues in a single model. Both models reproduce several characteristic properties of the hawkmo...

The users of today's commercial prosthetic hands are not given any conscious sensory feedback. To overcome this deficiency in prosthetic hands we have recently proposed a sensory feedback system utilising a "tactile display" on the remaining amputation residual limb acting as man-machine interface. Our system uses the recorded pressure in a hand pr...

We investigating the role of anticipation and attention in a dynamic environment in a number of large scale simulations of an agent that tries to negotiate a number of gates that continuously open and close. In particular we have looked at learning mechanisms that can predict the future positions of the gates and control strategies that will allow...

A major drawback with myoelectric prostheses is that they do not provide the user with sensory feedback. Using a new principle for sensory feedback, we did a series of experiments involving 11 healthy subjects. The skin on the volar aspect of the forearm was used as the target area for sensory input. Experiments included discrimination of site of s...

The Ikaros project started in 2001 with the aim of developing an open infrastructure for system-level brain modeling. The system has developed into a general tool for cognitive modeling as well as robot control. Here we describe the main parts of the Ikaros system and how it has been used to implement various cognitive systems and to control a numb...

No current commercially available myoelectrically controlled prosthetic hands provide conscious sensory feedback to the user. A system aiming at relocation of sensory input from a prosthetic hand equipped with force sensors to the forearm skin of amputees, a tactile display, has been developed and constructed. The system consists of five piezoresis...

We have implemented and compared four biologically motivated self-organizing haptic systems based on proprioception. All systems employ a 12-d.o.f. anthropomorphic robot hand, the LUCS Haptic Hand 3. The four systems differ in the kind of self-organizing neural network used for clustering. For the mapping of the explored objects, one system uses a...

A conceptually novel prosthesis consisting of a mechatronic hand, an electromyographic classifier, and a tactile display has been developed and evaluated by addressing problems related to controllability in prosthetics: intention extraction, perception, and feeling of ownership. Experiments have been performed, and encouraging results for a young t...

BERRY III is an interactive tool for the construction and simulation of neural network controlled artificial creatures that can be considered either as biological models or as simulated robots. Environments and creatures can be built and modified during simulation time using a large set of graphical editors and viewers. The simulator also includes...

The core deficit in attention deficit/hyperactivity disorder (ADHD) continues to present an enigma to scientists, professionals and parents alike. Medication with methylphenidate has to some extent proven successful, but it is still not known exactly what parts of the deficits in ADHD medication influences. It is thus important to further delineate...

The paper presents a general architecture for behaviour based control systems for autonomous agents. A number of archi tectural principles are proposed which make it possible to combine reactive control with learning and problem solving in a coherent way. In particular, I investigate the interaction between reinforcement learning, internal world mo...

We describe how a standard reinforcement learning algorithm can be changed to include a second contextual input that is used to modulate the learning in the original algorithm. The new algorithm takes the context into account during relearning when the previously learned actions are no longer valid. The algorithm was tested on a number of cognitive...

Introduction To act in an unknown and continously changing environment, an autonomous robot must be able to react instantaneously on changes and unexpected events in order to avoid collisions and to update its maps. Successful navigation requires that the robot reacts primarily on its immediate sensory information and secondarily on its internal ma...

We present a study of a novel variant of the Self-Organizing Map (SOM) called the Associative Self-Organizing Map (A-SOM). The A-SOM is similar to the SOM and thus develops a representation of its input space, but in addition it also learns to associate its activity with the activity of one or several external SOMs. The A-SOM has relevance in e.g....

A model of emotional conditioning is ex-tended with a cortical model where stimulus codes compete for activation. This system is combined with motivational inputs that mod-ulate both sensory and emotional processing. The extended model is able to reproduce the attentional blocking effect. It can also learn to switch between different sensory target...

A self-organizing neural network is described that can associate between different modalities and also has the ability to learn perceptual sequences. This architecture is a step towards the development of a complete agent containing simplified versions of all major neural subsystems in a mammal. It aims at exploring as well as takes inspiration fro...

The moth Macroglossum stellatarum can learn the color and sometimes the odor of a rewarding food source. We present data from 20 different experiments with different combinations of blue and yellow artificial flowers and the two odors, honeysuckle and lavender. The experiments show that learning about the odors depends on the color used. By trainin...

We have experimented with different neural network based architectures for bio-inspired self-organizing texture and hardness perception systems. To this end we have developed a microphone based texture sensor and a hardness sensor that measures the compression of the material at a constant pressure.We have implemented and successfully tested both m...

The active vision and attention-for-action frameworks pro- pose that in organisms attention and perception are closely integrated with action and learning. This work proposes a novel bio-inspired integrated neural-network architecture that on one side uses attention to guide and furnish the parameters to action, and on the other side uses the effec...

This book has provided various theoretical perspectives on anticipatory processes in natural and artificial cognitive systems. Advantages have been proposed and confirmed in various detailed case studies, which may have given the reader detailed insights into anticipatory processes and their importance in various cognitive systems tasks. To wrap up...

To successfully interact with a dynamic world, our actions must be guided by a continuously changing anticipated future. Such anticipations must be tuned to the processing delays in the nervous system as well as to the slowness of the body, something that requires constant adaptation of the predictive mechanisms, which in turn require that sensory...

We have implemented four bio-inspired self-organizing haptic systems based on proprioception on a 12 d.o.f. anthropomorphic robot hand. The four systems differ in the kind of self-organizing neural network used for clustering. For the mapping of the explored objects, one system uses a Self-Organizing Map (SOM), one uses a Growing Cell Structure (GC...

How can visual selective attention guide eye movements so as to collect information and identify targets potentially relevant for action? Many models have been proposed that use the statistical properties of images to create a dynamic bottom-up saliency map used to guide saccades to potentially relevant locations. Since the concept of saliency map...

We investigated the role of the length of the future time interval in which an agent predicts what will happen. A number of simulated robot experiments were performed where four thieves try to collect pieces of gold from a house that is guarded by a single robot. The thieves try to anticipate the movement of the guard to select behaviors that will...

A reinforcement architecture is introduced that consists of three complementary learning systems with different generalization abilities. The ACTOR learns state-action associations, the CRITIC learns a goal-gradient, and the PUNISH system learns what actions to avoid. The architecture is compared to the standard actor-crititc and Q-learning models...

A model of event driven anticipatory learn-ing is described and applied to a number of attention situations where one or several vi-sual targets need to be tracked while being intermittently occluded. The model combines covert tracking of multiple targets with overt control of a single attention focus. The im-plemented system has been applied to bo...

Infants gradually learn to predict the motion of moving targets and change from a strategy that mainly depends on saccades to one that depends on anticipatory control of smooth pursuit. A model is described that combines three types of mechanisms for gaze control that develops in a way similar to infants. Initially, gaze control is purely reactive,...

Three different models of tactile shape perception inspired by the human haptic system were tested using an 8 d.o.f. robot hand with 45 tactile sensors. One model is based on the tensor product of different proprioceptive and tactile signals and a self-organizing map (SOM). The two other models replace the tensor product operation with a novel self...

During the years 2005 and 2006 a robot system has been developed at Lund University Cognitive Science to run navigation ex-periments in a dynamic environment. The main aim of the system is to study anticipation during navigation, model building, color tracking, navigation algorithms, social robotics and children's games. This techni-cal report desc...

The Lucs Haptic Hand III has been built as a step in a project at LUCS aiming at studying haptic perception. In this project, several robot hands together with cog- nitive computational models of the corresponding hu- man neurophysiologic systems will be built. Grasping tests with the LUCS Haptic Hand III were done with six different objects in ord...

This report describes a fast method for finding regions with a particular color in a visual scene. The method is general enough to be used in any situations were a number of objects with known color need to be found in an image. We demon- strate how the algorithm can be used to find and track robots wi th colored markers, symbols with a particular...

The Ikaros project started in 2001 with the aim at de- veloping an open infrastructure for system-level brain modeling. The system has developed into a general tool for cognitive modeling as well as robot control. This report describes the main parts of the Ikaros system, in particular the simulation kernel, and sum- marizes the work done within th...

We have experimented with proprioception in a bio-inspired self-organizing haptic system. To this end a 12 d.o.f. anthropomorphic robot hand with proprioceptive sensors was developed. The system uses a self-organizing map for the mapping of the explored objects. In our experiments the system was trained and tested with 10 different objects of diffe...

Cognitive explanations of autism often involve higher order cognitive functions developing late in childhood, such as theory of mind, executive functions or central coherence. In home videos of infants later diagnosed with autism, children display early signs of developmental disorders, for example impaired sensorimotor functions, attention to soci...

This chapter outlines an approach to building robots with anticipatory behaviour based on analogies with past episodes. Anticipatory mechanisms are used to make predictions about the environment and to control selective attention and top-down perception. An integrated architecture is presented that perceives the environment, reasons about it, makes...

This paper presents an experimental study using two robots. In the experiment, the robots navigated through an area with or without obstacles and had as their goal to shift places with each other. Four dif- ferent approaches (random, reactive, planning, anticipation) were used during the experiment and the times to accomplish the task were com- par...

The moth Macroglossum stellatarum can learn the colour and sometimes the odour of a rewarding food source. We present data from 20 different experiments with different combinations of blue and yellow artificial flowers and the two odours honeysuckle and lavender. The experiments show that learning about the odours depends on the colour used. By tra...

This paper proposes a new learning set-up in the field of control systems for multifunctional hand prostheses. Two male subjects with a traumatic one-hand amputation performed simultaneous symmetric movements with the healthy and the phantom hand. A data glove on the healthy hand was used as a reference to train the system to perform natural moveme...

This paper presents an experimental study using two robots. In the experiment, the robots navigated through an area with or without obstacles and had as their goal to shift places with each other. Four dif-ferent approaches (random, reactive, planning, anticipation) were used during the experiment and the times to accomplish the task were com-pered...

To accurately track a moving target despite delays in the visual processing, it is necessary to predict how the target will move in the future and to direct the gaze toward the anticipated location. We have ad-dressed this problem within a simulated visual scene were a ball is dropped from a random location and subsequently bounces or rolls on diff...

We have developed an 8 d.o.f. robot hand which has been tested with three computational models of haptic perception. Two of the models are based on the tensor product of different proprioceptive and sensory signals and a self-organizing map (SOM), and one uses a novel self-organizing neural network, the T-MPSOM. The computational models have been t...