Spring 2012

February 6: 4:00 in PY 101

Using Human-Robot Interactions to Study Human-Human Social Behavior
Brian Scassellati
Department of Computer Science
Yale University

Robots offer a unique tool in the study of human social behavior because they offer a completely controllable, and infinitely repeatable, stimulus that respond precisely to only select social cues and without observer bias. In this talk, I'll present some results from human-robot interactions on topics that include cheating and compliance, social learning and instruction, and animacy and agency. Finally, I'll offer some preliminary data on how these robots can be used as therapeutic and diagnostic tools for social deficits such as autism spectrum disorder. (Background Paper)

March 19: 4:00 in PY 101

The Integration Challenge in Cognitive Science and the Promise of Embodied Neural Dynamics
John Spencer
Department of Psychology
University of Iowa

For the last decade, my colleagues and I have been developing a theoretical framework--the Dynamic Field Theory (DFT)--to handle four central challenges any theory of cognition must address. In my talk, I will present an overview of these challenges as well as empirical and theoretical examples to highlight how DFT handles each in turn. The first challenge is created by the reality of neural systems: how does the brain realize stable, flexible behavior given the massive reentrance and complexity of neural systems? Here, I will describe a population dynamics approach to neural function and how this approach bridges the gap between brain and behavior. The second challenge is created by embodiment: how do brains deal with the real-time details of sensori-motor systems in a body in an environment? Addressing this challenge requires the concept of stability from dynamical systems theory, a concept central to DFT. The third challenge is to integrate processes over multiple timescales: what processes integrate real-time perception-action-cognition with learning and development? I will highlight how different variants of Hebbian learning within DFT can give rise to both supervised and unsupervised changes over time. Finally, theories of cognition must scale up from lower-level to higher-level cognition. Here, I will emphasize recent examples from spatial language and executive control that demonstrate that DFT scales up to abstract forms of cognition. (Background Paper 1, Background Paper 2)

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Fall 2011

October 24: 4:00 in PY 101

Neuromodulation as a Brain-Inspired Strategy for Controlling Autonomous Robots and a Means to Investigate Social Cognition during Human-Robot Interactions
Jeffrey Krichmar
Dept. of Cognitive Sciences
Dept. of Computer Science
University of California at Irvine

Biological organisms have the ability to respond quickly to an ever-changing world. Because this adaptability is so critical for survival, all vertebrates have sub-cortical structures, which comprise the neuromodulatory systems, to regulate fundamental behavior and drive decision-making in response to environmental events. In the vertebrate, there are separate neuromodulators that respond to threats, reward anticipation, novelty, and attentional effort. However, each of these neuromodulatory systems has a similar effect, that is, to cause an organism to be decisive when environmental conditions call for such actions, and allow the organism to be more exploratory when there are no pressing events. We used a cognitive robot, CARL, to test the hypothesis that neuromodulatory activity can shape learning, drive attention, and select actions. CARL learned to approach stimuli that were predictive of positive value and move away from stimuli that were predictive of negative value. An intact neuromodulatory system was necessary for correct behavioral responses and for appropriate neuromodulatory responses to stimuli. In a set of Human-Robot interaction experiments, we investigated the neural basis of social decision-making by having subjects play Hawk-Dove and Chicken games with simulated and embodied agents that adapt to their opponent's strategy and environmental conditions. The model controlling the agent was based on assumptions that dopaminergic and serotonergic systems track expected rewards and costs, respectively. In a double blind study, subjects' serotonin levels were lowered through acute tryptophan depletion (ATD). Subjects switched from a win-stay, lose-shift to a tit-for-tat strategy when playing against aggressive agents. Iterative interactions with responsive agents outweighed the effects of ATD and embodiment, highlighting the importance of human interactions with adapting agents. These experiments suggest a mechanism of how neuromodulatory systems influence attention and decision-making. (Background Paper)

November 28: 4:00 in PY 101

Interaction-Dominant Dynamics, Phenomenology, and Extended Cognition
Anthony Chemero
Psychology
Franklin & Marshall College

One of the more lively current debates in philosophy of cognitive science and philosophy of mind is over the possibility of extended cognition. Recently, though, this debate has hit a dead end, with proponents and opponents agreeing that whether cognition is sometimes extended is an empirical matter, but not knowing what an empirical demonstration of extended cognition would look like. In this talk, I will present an unequivocal empirical demonstration of an extended cognitive system. It will also be a semi-equivocal empirical demonstration of phenomenological philosopher Martin Heidegger's proposed transition from readiness-to-hand to unreadiness-to-hand. I will describe a series of experiments designed to induce and then temporarily disrupt an extended cognitive system. Participants in these experiments played a simple video game, controlling an object on a monitor using a mouse. At some point during the trial, the connection between the mouse and the object it controls is disrupted temporarily before returning to normal. We found 1/f scaling at the hand-mouse interface while the mouse was operating normally, and found that this 1/f scaling is reduced during the perturbation. This indicates that, during normal operation, the computer mouse is part of the smoothly functioning interaction-dominant system engaged in the task. That is, the participant and tool constitute a self-assembled, extended device during smooth coping and this device is disrupted by the perturbation. These experiments were designed to detect, and did in fact detect, the presence of an extended cognitive system, a system that included both biological and non-biological parts. The fact that such a mundane experimental setup (using a computer mouse to control an object on a monitor) generated an extended cognitive system suggests that extended cognitive systems are quite common. They also provide evidence for Heidegger's proposed transition from readiness-to-hand to unreadiness-to-hand. (Background Paper)

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Spring 2011

January 24: Hod Lipson, Mechanical and Aerospace Engineering, Cornell University, "Self-reflective machines"

March 21: Lawrence Barsalou, Department of Psychology, Emory University, "Grounding Knowledge in the Brain's Modal Systems"

April 4: Susan Goldin-Meadow, Department of Psychology, University of Chicago, "How Our Hands Help Us Think"

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Fall 2010

September 13: Michael Richardson, Center for Cognition, Action and Perception, Psychology Department, University of Cincinnati, "Affording structured coordination: An ecological approach to self-organized social action"

October 18: Ennio Mingolla, Department of Cognitive and Neural Systems, Department of Psychology, Boston University, "Neural models of visually-guided steering, obstacle avoidance, and route selection"

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Spring 2010

February 22: Mary Hayhoe, Dept. of Psychology, The University of Texas at Austin, "Adaptive Control of Attention and Gaze in the Natural World".

February 24: Dana Ballard, Dept. of Computer Sciences, The University of Texas at Austin, "Modular Reinforcement Learning as a Model of Embodied Cognition".

April 5: Asif Ghazanfar, Dept. of Psychology, Princeton University, "Vocal Communication Through Coupled Oscillations: Substrates for the Evolution of Speech".