Cochlear implants have the potential to provide hearing to people who would otherwise be deaf, and to allow them to understand speech even without the aid of lipreading. Despite this tremendous success, cochlear-implant users (as well as people with much milder forms of hearing loss) often have great difficulty understanding speech in the presence of noise or other interfering sounds. This talk will review some recent research aimed at understanding normal and abnormal auditory processing of speech with the long-term goal of improving communication abilities of people with hearing difficulties in our noisy everyday acoustic environments.

Suggested reading:

• Oxenham AJ (2013) Revisiting place and temporal theories of pitch. Acoust. Sci. & Tech. 34, 6
• Smith ZM, Delgutte B, Oxenham AJ 2002 Chimaeric sounds reveal dichotomies in auditory perception. Nature, 416, 87-90

 

Schizophrenia is believed to result from a loss of normal synaptic communication between neurons. However, we do not understand how a loss of synaptic function distorts electrophysiological dynamics in cortical neurons and networks to produce the clinical symptoms and cognitive deficits that characterize the disease. To link cognitive deficits in schizophrenia to their underlying neural causes, we have developed a nonhuman primate model of the disease. By blocking synaptic communication at NMDA glutamate

receptors in nonhuman primates, we have been able to replicate behavioral deficits in cognitive control that closely parallel those seen in the patient population. Characterizing neural activity in prefrontal cortex and connected areas during the period of cognitive impairment is beginning to reveal how cortical neuron and network function is disrupted by synaptic failure in the disease state.

Suggested reading:

• Crowe D, et al. (2014) Prefrontal neurons transmit signals to parietal neurons that reflect executive control of cognition. Nature Neuroscience, 16, 10, 1484:1491
• Blackman RK, MacDonald III, AW, Chafee MV (2013) Effects of Ketamine on Context-Processing Performance in Monkeys: A New Animal Model of Cognitive Deficits in Schizophrenia. Neuropsychopharmacology 38 2090:2100

Empathy entails the ability of an animal to infer the emotional state of another. Such an emotional capacity requires an integrated set of behavioral, affective, and cognitive processes. In humans, disruption of these processes is hypothesized to underlie the social cognition or ‘theory of mind’ deficits evident in schizophrenia, autism, and psychopathy. While the importance of empathy has been exemplified by psychiatric disorders, relatively little is known about its exact neurobiological substrates.

In order to elucidate the origins of empathetic processes in the brain, development and application of non-human models is paramount. Towards this end, evidence has emerged to suggest that lower-order mammals also embody rudimentary forms of empathy and may serve as highly tractable model systems. One of my research projects aims to develop and validate a paradigm for measuring social fear transmission and learning in mice, as well as to examine this empathy-like behavior using intranasally-administered neuropeptides and genetically-modified mouse models. Ultimately, such research may inform our understanding of the neurobiological underpinnings of empathy, as well as the impairments of social cognition in psychiatric disease.

Suggested reading:

• Panksepp JB & Lahvis GP (2011) Rodent empathy and affective neuroscience. Neuroscience and Biobehavioral Reviews 35,1864–1875

 

The current focus of my research is on control, perception and planning in interactive tasks such as found when flying in unknown environments, ski racing or performing delicate surgery. Tackling the technical and scientific challenges associated with the design of autonomous systems inevitably raises questions about how humans achieve their skills. Skilled pilots, like virtuoso musicians or accomplished athletes, depend on thousands of hours of systematic training. During that time they exercise a wide array of brain functions ranging from fine motor control, to perception, planning and cognition. This system is challenging to formally characterize and model.

Guidance involves a range of dynamic interactions, encompassing the dynamics of the vehicle and entire human-machine or agent-environment interactions. Therefore, principles from dynamics and control play a central role in shaping the entire system of control, perceptual and planning processes. Instead of attempting to dissect and describe these individual components, my research philosophy has been to experimentally investigate the scope of whole system patterns of interactions and determine how these can be used to delineate and model sub-system processes and their integration. In this talk, I will present an overview of the laboratory facility, experiments, and modeling techniques that are being developed in the Interactive Guidance and Control Lab (IGCL).

Suggested reading:

• Mettler B (2011) Structure And Organizational Principles Of Agile Behavior: Challenges And Opportunities In Cognitive Engineering. Cognitive Critique, 3 1:22
• Kong Z & Mettler B (2013) Modeling Human Guidance Behavior Based on Patterns in Agent-Environment Interactions. IEEE Transactions On Human-Machine Systems, 43, 4

 

In this colloquium, I will introduce several qualitative and quantitative methods developed for analyzing responses to two standard neuropsychological tests of verbal fluency — phonemic and semantic. On these tests the participants are asked to name as many words as they can in a short time (usually 60 seconds) that either begin with a certain letter of the alphabet or belong to a certain semantic category (e.g. animals). The responses to these tests are widely used to assess the degree of impairment to semantic memory and executive function and are a part of several cognitive testing batteries used in the diagnosis of dementia. Apart from the traditional score consisting of a valid word count, several additional test characteristics have been examined including clustering behavior that results in sequences of words that are similar either semantically or phonetically. The majority of previous studies of clustering behavior relied on manual qualitative determination of cluster, a labor intensive and error-prone process that is not scalable to large samples. I will present several quantitative alternatives to measuring the size of semantic and phonemic clusters based on computational linguistic approaches and discuss their strengths and limitations in the context of developing behavioral biomarkers for Alzheimer’s disease.

 

That students’ knowledge base often contains previously-acquired-but-no-longer correct information that is difficult to change through teaching is well-established. In many learning environments texts actually present correct information that runs counter to students’ inaccurate knowledge. In these instances, learning of new information necessitates knowledge revision. In this talk, I will discuss a series of studies that examine the incremental steps of knowledge revision, detailing its time course and mechanisms during reading comprehension in the context of a new theoretical framework, the Knowledge Revision Components framework (KReC; Kendeou & O’Brien, in press). KReC aligns itself nicely with what we know about knowledge revision in the context of reading comprehension and has implications for research in single and multiple text comprehension, conceptual change, persuasion, and the misinformation effect.

Suggested reading:

• Kendeou P, Smith ER & O'Brien EJ (2013) Updating during reading comprehension: why causality matters. J Exp Psy, 39, 3 854:865

 

My research focuses on the development of strategies to enhance the effectiveness with which virtual environments technology can be used for a variety of purposes, from architectural design and visualization to neurocognitive assessment. In this talk I will discuss our current efforts in two key areas: self-embodiment and locomotion.

After briefly reviewing our previous findings on the impact on distance estimation accuracy of providing people with self-embodiments of varying degrees of fidelity, I will outline two different implementation strategies we are currently pursuing to enable more realistic self-embodiment in VR, including the challenges and concerns as well as the benefits we hope to achieve through each approach. As this is very much work-in-progress, however, I will have fewer answers than questions on most points.

Next I will turn to the topic of locomotion. Our current research interest is in determining how to use various capabilities of physical locomotion to best effect in different virtual environment applications. We have developed a redirection controller for a motorized wheelchair, that enables us to use it within the confines of a large room as a sort of low-cost, low-fidelity motion simulator. We have so far concentrated on measuring thresholds for the detectability of a dissociation between the visually presented and physically sensed movements, by movement type and intensity, but going forward we are interested in determining the extent to which, and conditions under which, providing physical motion feedback in VR can continue to be of benefit in supporting spatial cognition under conditions of supra-threshold visual/vestibular conflict.

 

High and low activity rats: elevated intrinsic physical activity drives resistance to diet-induced obesity.

Background: Humans and rodents show large variability in their individual sensitivity to diet-induced obesity (DIO), which has been associated with differences in intrinsic spontaneous physical activity (SPA). Evidence from genetic and out-bred rat obesity models shows that higher activity of the orexin peptides results in higher intrinsic SPA and protection against DIO. Based on this, we hypothesized that naturally occurring variation in SPA and orexin signaling is sufficient to drive differences in sensitivity to DIO, and that brain orexin administration would be sufficient to prevent DIO caused by high-fat diet feeding.

Methods: To test these ideas, orexin expression, behavioral responses to orexin-A, basal energy expenditure and sensitivity to DIO were measured in non-manipulated male Sprague-Dawley rats selected for high and low intrinsic SPA. In a separate study, rats were fed either a high fat diet (HF; 45% kcal from fat) or low-fat diet, and received daily orexin injections (500 pmol) into RLH.

Results: Male Sprague-Dawley rats were classified as high-activity or low-activity based on differences in intrinsic SPA. High-activity rats showed higher expression of prepro-orexin mRNA, higher sensitivity to behavioral effects of orexin injection, higher basal energy expenditure and were more resistant to obesity caused by high-fat diet consumption than low-activity rats. Furthermore, daily injections of orexin peptide in RLH prevented DIO without altering food intake.

Conclusion: These data define a new model of differential DIO sensitivity, the high-activity and low-activity rats, and suggest that naturally occurring variations in intrinsic SPA cause differences in energy expenditure that are mediated by orexin signaling and alter DIO sensitivity. Additionally, orexin therapy to drive physical activity may be considered as a potential therapeutic tool for preventing diet-induced obesity.

Suggested readings:

Long-term, intermittent, insulin-induced hypoglycemia produces marked obesity without hyperphagia or insulin resistance: a model for weight gain with intensive insulin therapy. McNay EC, Teske JA, Kotz CM, Dunn-Meynell A, Levin BE, McCrimmon RJ, Sherwin RS.Am J Physiol Endocrinol Metab. 2013 Jan 15;304(2):E131-8.

Behavioral responses to orexin, orexin receptor gene expression, and spontaneous physical activity contribute to individual sensitivity to obesity. Perez-Leighton CE, Boland K, Teske JA, Billington C, Kotz CM.Am J Physiol Endocrinol Metab. 2012 Oct 1;303(7):E865-74.

Role of orexin receptors in obesity: from cellular to behavioral evidence. Perez-Leighton CE, Butterick-Peterson TA, Billington CJ, Kotz CM. Int J Obes (Lond). 2013 Feb;37(2):167-74. doi: 10.1038/ijo.2012.30. Epub 2012 Mar 6. Review.

Studies of the brain and cognition are frequently susceptible to the appeal of "large project" solutions (e.g., Human Brain Project, BRAIN initiative, Allen Brain Atlas). While these endeavors are undeniably relevant to solving questions surrounding brain function, they often overshadow the complexity and heterogeneity of the research questions involved, including their relations to one another. In this talk I sketch a conceptual framework for thinking about the structure of scientific problems in studies of the brain and cognition that can capture why successfully prosecuting these studies requires multiple, diverse methodologies, and therefore is inherently interdisciplinary, but also suggests that "large project" solutions can be counterproductive in achieving the desired investigative aims. This exposes a tension between fruitful epistemological strategies and attempts to secure grants in the current funding environment.

Suggested reading:

Love A (2008) From Philosophy To Science (To Natural Philosophy): Evolutionary Developmental Perspectives. The Quarterly Review Of Biology, 83, 1

Scott D. Lipscomb,¹ Guerino Mazzola,¹ & Erkki Huovinen²

1 University of Minnesota – Twin Cities; Minneapolis, MN, USA
2 University of Jyväskylä; Jyväskylä, Finland

During this session, Dr. Lipscomb will present results of a series of quasi-experimental investigations, the primary purpose of which was to determine whether the presence of a visual component enhances to a significant degree the music listening experience of listener-viewers in response to examples varying in the level of musical complexity (moderately complex traditional examples and highly complex avant-garde examples), genre (jazz and art music), and stimulus presentation condition (audio only, audio with algorithmic visualization, or audio with visual performance data). Results of each experiment will be presented, each building upon the results of the previous. In addition to the primary results sought, the presentation will also address design issues that emerged and were revised in order to improve the reliability and validity of the experimental procedures.

In later experiments, a block design (rather than independent groups) was utilized so that every participant experienced excerpts not only of each musical genre and various levels of complexity, but stimuli representing each of the three A-V conditions enumerated above. Quantitative data in the form of verbal scale responses were collected, along with responses to open-ended questions that revealed participants’ underlying rationales for ratings provided. Results of the investigation revealed a clear preference for less complex music, but also confirmed that adding a visual component (either performance data or algorithmic visualization) resulted in more positive evaluative ratings for avant-garde musical examples. Dr. Lipscomb will address relevant implications of this outcome when introducing music in the classroom that falls outside the “comfort zone” of students enrolled.

 

• Sperber D, et al. (2010) Epistemic Vigilance. Mind & Language, 25, 4, 359-393
• Koenig MA & Stephens E (in press) Characterizing Children’s Responsiveness to Cues of Speaker Trustworthiness: Two Proposals. To appear in E. Robinson and S. Einav (Eds.), Trust and Skepticism: Children's Selective Learning from Testimony. Psychology Press: Cambridge, UK.
• Koenig MA, Clément F & Harris PL (2004) Trust in Testimony: Children’s Use of True and False Statements. Psychological Science 15, 10, 694-698