Tiffany Schmidt, Johns Hopkins University
"Role for melanopsin in alpha retinal ganglion cell physiology and contrast detection"
Distinct populations of retinal ganglion cells (RGCs) drive image forming and non-image forming vision. Intrinsically photosensitive (ip)RGCs express the photopigment melanopsin and drive non-image forming functions such as circadian photoentrainment and the pupillary light reflex. Ablation of ipRGCs results in loss of non-image forming behaviors, but intact rod/cone dependent image forming vision. These findings have led to the conclusion that ipRGCs mediate non-image forming vision, while conventional RGCs mediate image formation via the relay of rod/cone signals. Despite the prevailing view that rod/cone signals through conventional RGCs mediate image forming vision and rod/cone/melanopsin signals through ipRGCs mediate non-image-forming vision, we find that a conventional RGC type, the ON alpha RGC, is intrinsically photosensitive. Furthermore, we find that melanopsin plays a role in the light-evoked responses of ON alpha RGCs, allowing these cells to signal both lighting history and changes in environmental luminance. These properties are dependent upon melanopsin phototransduction because in the absence of the melanopsin protein, ON alpha RGCs lose their intrinsic photosensitivity, and show a reduction in their ability to encode lighting history and environmental irradiance. Consistent with the high contrast sensitivity of alpha RGCs, animals lacking melanopsin have a clear deficit in visual contrast sensitivity as assayed by optokinetic tracking, demonstrating that melanopsin plays an unexpected role in contrast detection. Thus, ON alpha RGCs utilize both rod/cone and melanopsin signals to mediate image formation.
Apostolos Georgopoulos, Director,
Center for Cognitive Sciences
"Exploring small city maps"
The goal of this research is to contribute to the elucidation of the brain mechanisms underlying spatial cognition in the context of exploring standard types of city maps. Specifically, we seek to understand the brain mechanisms involved in interactions with maps which range from open exploration to targeted wayfinding in order to construct a model of how the spatial properties of environment represented in maps interact with cognitive processes. A longer term practical application is to help design navigation devices and representations of the spatial environment that not only assist wayfinding directed to specified destinations but also assist broader learning of the spatial environment to support a open range of individual and collective behaviors. Another longer term aim is to support the design of more intelligible environments by extending current knowledge regarding the effects of specific properties of layouts on cognitive performance.
Yerkes Primate Center / Georgia State University
"Left, Right, Hand and Brain: Evolution of Hemispheric Specialization in Primates"
Hemispheric specialization refers to sensory, motor and cognitive processes that are differentially represented in the left and right hemispheres. Two of the most robust expressions of hemispheric specialization in humans are right-handedness and left hemisphere dominance for language and speech. Furthermore, most right handed individuals are left hemisphere dominant for language. Historically, many have suggested that right handedness and left hemisphere asymmetries in communicative functions arose during evolution after the split between humans and chimpanzees with the common ancestor around 6 mya. This salational view of the evolution of hemispheric specialization has been challenged by recent findings in nonhuman animals, notably primates. Here, I present findings on handedness and other aspects of behavioral asymmetries in nonhuman primates with an emphasis on studies with chimpanzees. I further present findings on neuroanatomical asymmetries in human and nonhuman primates as measured from magnetic resonance imaging (MRI) in two key brains regions involved in language including Wernicke’s and Broca’s area. The collective results are discussed within the context of the role of hemispheric specialization in the evolution of higher order cognitive and motor functions in modern humans.
Travis Thompson, Special Education Program, Department of Educational Psychology,
"Blended Autism Intervention: Early Intervention Theory and Evidence"
Despite frequent claims of little progress in autism research and practice, longitudinal studies show that the percentage of children with autism reaching “best outcomes” has increased from 1-2% to about 50% over the past 40 years. Research publications have increased from a few per year to over 2,000 articles annually over that time period. Controversy over alternative interventions stems from very different epistemological traditions, i.e. assumptions of constructivist and attachment theory-based approaches conflict with behavior analytic approaches. Dr. Thompson will present evidence concerning the efficacy of different approaches, while making a case for using Blended Intervention strategies.
Let me not to the marriage of true minds which alters when it alteration finds, love alters not with his brief hours and weeks. But bears it out even to the edge of doom. Or bends with the remover to remove.
Gordon Legge, Department of Psychology
"The Visual Accessibility of Indoor Spaces"
The visual accessibility of a space refers to the effectiveness with which vision can be used to travel safely through the space and to pursue the intended activities in the space. Visual accessibility has an important impact on low-vision mobility. I will describe our empirical approach for studying the visual accessibility of indoor spaces, including experiments on the detection and recognition of steps and ramps. I will also describe and demonstrate our development of a new form of adaptive technology — the “Digital Sign System” — to assist visually-impaired people with indoor navigation.Reference:
Maria Sera, Institute for Child Development
"Second Language Learning in the Preschool Years"
Understanding how young children learn a second language is important on both theoretical and practical grounds. From a theoretical standpoint, this evidence is relevant to understanding how languages are learned. From a practical standpoint, this evidence may be relevant to developing strategies that accelerate second language learning for children who enter educational systems knowing a different native language. In this talk, I will summarize evidence from two studies. One is a longitudinal (correlational) study of native Spanish-speaking preschoolers learning English. The second source of evidence comes from laboratory experiments of native English speakers learning a foreign language. Evidence from both studies indicates that second-language learning, even by young children, may not be as fast as many might believe. The results also point to vocabulary size as an early rate-limiting factor. Strategies for accelerating early second language learning suggested by the evidence will also be discussed.
Francis Shen, Law School
"Law and Neuroscience: Hope, Hype, and How to Tell the Difference"
Recent years have seen tremendous growth in neuroscience evidence in court and legislatures. These recent developments include: the first hearing on admissibility of fMRI lie detection evidence; the first admission of qEEG evidence for a reduced sentence in a homicide case; and the U.S. Supreme Court citing brain development research in multiple cases. These and other developments give rise to legitimate hope that in some contexts, law and policy may be meaningfully improved through integration of brain science. But they have also given rise to much over-stated hype about the ways in which the science will and should be used. This presentation aims to distinguish between the two. Dr. Shen will discuss topics such as brain-based memory and lie detection; adolescent brain development and criminal responsibility; and the evidentiary challenges faced by courts and legislatures in evaluating neuroscientific data. The talk will emphasize the distinction between scientific certainty versus legal certainty, and how this difference animates much of the debate about whether, and how, neuroscience should be used in law. Dr. Shen will also discuss how the MacArthur Foundation Research Network on Law and Neuroscience at www.lawneuro.org is addressing many of these issues.
Anna Johnson, Graduate student, Institute for Child Development
"Early Life Adversity and the Development of Self-Regulation"
Self-regulation is a multidimensional process that allows for the willful control of thoughts, emotions, and behavior. The capacity to self-regulate improves throughout childhood and adolescence, and is associated with a variety of positive outcomes, such as academic achievement, positive peer relationships, and physical and mental health. In this talk, I will discuss the impact of early life adversity on the development of self-regulation among children and adolescents who were adopted internationally from orphanage care. Specifically, I will present a series of studies that examine the impact of early institutional care on behavioral and neurobiological measures of cognitive control, emotion regulation, and stress reactivity. Future directions regarding the training of self-regulation and potential sensitive periods for intervention will be discussed.
Michael Wade, School of Kinesiology
"Atypical motor development: A case of disrupted perception-action synergy"
It is well known that children with a range of developmental deficits show delays in reaching the accepted 'motor milestones', and the elderly become more susceptible to falling as they age For many years the relationship between changes in,or anomalies in the biology (biomechanics) were not related to changes in, or anomalies to the behavioral system (perception or cognition). Our data, on children with dyspraxia and elderly individuals with clinically diagnosed dementia, show atypical responses to their postural stability while engaged in supra-postural tasks requiring either perceptual or cognitive effort. These data are discussed with respect to the link between perception and action.
Shmuel Lissek, Department of Psychology
"Generalization of Classically Conditioned Fear: Psychophysiology, Neurobiology, and Clinical Relevance"
Meta-analytic results of fear-conditioning studies in the anxiety disorders implicate generalization of conditioned fear to stimuli resembling the conditioned danger cue as a robust conditioning marker of anxiety pathology. Unfortunately, no psychobiological studies prior to the current program of work have examined this generalization process in any of the anxiety disorders using systematic generalization-gradient methods developed in animals. Generalization gradients refer to slopes of conditioned responding that decline as the test stimulus gradually differentiates from the conditioned danger-cue. The current program of work was designed to fill this gap by elucidating the behavioral, psychophysiologic, and neurobiologic correlates of continuous generalization-gradients in adults with and without clinical anxiety. The employed paradigm consists of quasi-randomly presented rings of gradually increasing size, with extreme sizes serving as conditioned danger- and conditioned safety-cues. The rings of intermediary size create a continuum-of-similarity between the conditioned danger- and safety-cue and are included to assess continuous gradients of fear generalization.
Presented results demonstrate overgeneralization of conditioned fear among anxiety patients with panic disorder (PD), generalized anxiety disorder (GAD), and posttraumatic stress disorder (PTSD), but not social anxiety disorder (SAD). Specifically, generalization gradients among PD, GAD, and PTSD patients were abnormally shallow reflecting less degradation of the conditioned fear response as the presented stimulus differentiated from the conditioned danger cue. Phenomenologically, such overgeneralization may proliferate anxiety cues in the individual's environment that are then capable of evoking and maintaining maladaptive anxiety and avoidance. The talk will next focus on harmful consequences of overgeneralization by presenting preliminary data from a new generalization experiment designed to capture maladaptive behavioral avoidance precipitated by conditioned generalization.
Michael Georgieff, Department of Pediatrics
"The role of fetal and neonatal iron in learning and memory"
The study of the effects of early experience on form-function relationships in the developing human brain necessitates an interdisciplinary approach spanning disciplines from molecular neuroscience through educational psychology. The burden of proof to demonstrate causality between early life risk factors and individual developmental outcome requires careful model building that bridges the “languages” inherent to each scientific discipline with a stake in the discussion. Approaches are can be top-down or bottom-up and are often both. Cross-species models commonly used in such research should be developmentally sensitive and respect critical or sensitive windows of development. While precise understanding of form-function relationships in complex psychopathologies (eg, schizophrenia, autism) may still be far off, approaches that have been used in studies of early nutrition and brain development can serve as a model. In this talk, I will explore how interdisciplinary approaches are used to understand the role of nutrients that are critical for normal brain development. Basic nutrient-brain interaction principles include the roles of timing, dose and duration in determining developmental risk to brain structures and processes. The role of iron in the developing brain will be used as the primary example although the talk will highlight a number of nutrients that are important in early brain-behavior development.
Marlene Zuk, Department of Evolution, Ecology, and Behavior
"Rapid evolution in silence: adaptive signal loss in the Pacific field cricket"
Because they are conspicuous, sexual signals often represent a compromise between natural and sexual selection. In part of its range, the Pacific field cricket Teleogryllus oceanicus is subject to an introduced parasitoid fly that finds its host using the cricket's song, which has caused numerous changes in calling behavior and song structure. Most recently, we have documented a more extreme and rapid change, the near disappearance of calling, in one population of the crickets, due to a wing mutation that renders males unable to call. This new morph is protected from the parasitoid, but faces obvious difficulties in mate attraction. Both the evolutionary origin of populations and the acoustic environment of the crickets during development appear to have facilitated the spread of this novel trait. Can behavior influence the mode and tempo of evolution?
April 26 (Friday)
Spring Research Day
Dennis M. Levi, Ph.D.
Dean for the School of Optometry & Helen Wills Neuroscience Institute, University of California Berkeley
"Removing the Brakes on Brain Plasticity in Adults with Amblyopia"
Experience-dependent plasticity is closely linked with the development of sensory function. Beyond this sensitive period, developmental plasticity is actively limited; however, new studies provide growing evidence for plasticity in the adult visual system. The amblyopic visual system is an excellent model for examining the “brakes” that limit recovery of function beyond the critical period. While amblyopia can often be reversed when treated early, conventional treatment is generally not undertaken in older children and adults. However new clinical and experimental studies in both animals and humans provide evidence for neural plasticity beyond the critical period. The results suggest that perceptual learning and video game play may be effective in improving a range of visual performance measures and importantly the improvements may transfer to better visual acuity and stereopsis. These findings, along with the results of new clinical trials, suggest that it might be time to re-consider our notions about neural plasticity in amblyopia.
Co-sponsors: UofM Department of Psychology and the Center for Cognitive Sciences
Wilma Koutstaal, Department of Psychology
“Think.” What do you suppose it means?… Our “thinking about thinking” and especially about creatively adaptive thought often takes a spotlight approach. We focus now on this aspect, now on that, and now on yet another, in a successive and fragmented part-by-part manner — but with few ways to keep it all together as a conceptually unified whole. In this talk, I introduce a broad integrative framework that helps us to conceptualize and empower our innovating minds. Applications and implications will be explored for fostering and sustaining mental agility across the lifespan, improving transdiagnostic understanding, shaping environmental affordances, and promoting individual and organizational improvisation.