Neuroscience Day at Dartmouth 2017

Join us for the 31st Annual Neuroscience Day at Dartmouth College!

This day-long event highlights neuroscience research contributions at Dartmouth and features expert talks, a poster session, a panel discussion, and a keynote lecture. Free and open to the public. Lunch will be provided to those who have registered by the registration close date.

Date
Saturday, April 8, 2017

Time
8:30 AM - 5:00 PM

Location
CLASS OF 1978 LIFE SCIENCES CENTER

Register and/or Submit a Poster Abstract


Important Dates

February 24, 2017
Registration and Abstract Submission Opens

March 29, 2017
Abstract Submission Closes

April 5, 2017
Registration Closes


Keynote Lecture:

"Building Action Repertoires Based on Value: Corticostriatal Dynamics"
Regions of the medial prefrontal cortex are known to function in
organizing behavior and emotional decision-making, both key functions
disturbed in a range of neurologic and neuropsychiatric disorders. In
our laboratory, we are seeking to understand mechanisms underlying these
functions by applying optogenetic manipulations and microstimulation to
these regions and their corticostriatal circuits. We find that we can
interrupt the transition from deliberative decision-making to a habitual
mode of decisions to act, and can interrupt habitual and insistently
repetitive behaviors. In other experiments, we can selectively disrupt
decision-making under different contexts involving weighing the costs
and benefits of such choices. These experiments point to profoundly
important functions of corticostriatal circuits and to their exquisite
specialization. These features could be critical in linking these
corticostriatal circuit mechanisms to human disorders in which
value-based decision-making is affected.
About the Keynote:

Ann Graybiel, PhD, Professor of Neuroscience, Department of Brain and Cognitive Sciences, M.I.T.; Investigator, McGovern Institute for Brain Research, M.I.T.

Ann M. Graybiel is an Institute Professor at MIT. Her research is focused on how the regions of the forebrain that influence movement, mood and motivation — the basal ganglia and neural pathways interconnecting the basal ganglia with the cerebral cortex — operate in normal and abnormal conditions. Dr. Graybiel and her group, in order to approach these issues, apply combinations of methods ranging from multi-electrode recordings from neurons in the brain to genetic engineering, optogenetics, fast-scan cyclic voltammetry and designer drug manipulations during behavior.

 


Faculty Speakers

 Michael Hoppa, DPhil Assistant Professor of Biology, Dartmouth College

Title: Excitement about Presynaptic Action Potentials!

Abstract: Our bodies run on electricity. The heart and brain among other organs rely on precise electrical signaling at the cellular level to operate. Voltage-gated calcium channels are fulcrums of neurotransmission that convert electrical inputs into chemical outputs in the form of vesicle fusion at synaptic terminals. Changes in calcium influx are powerful regulators of synaptic strength and critical to our understanding synaptic plasticity. However, the role of the electrical signal, the presynaptic action potential waveform, to modulate calcium and synaptic transmission is less clear. A fundamental barrier to measure electrical signaling in the axon of mammalian neurons is their small size that makes them inaccessible for whole-cell patch clamp recording.  Our research group has overcome these measurement limitations by developing precise optical approaches to quantify membrane voltage at sub-millisecond detection speeds.  This talk will first discuss fundamental discoveries using these optogenetic indicators in hippocampal neurons. Second, we will report newly discovered mechanisms of local sculpting of the AP waveform throughout axonal arborization that are relevant to understanding the flow of excitation in the brain.

Bio: Michael B Hoppa is an Assistant Professor in the Department of Biological Sciences at Dartmouth, where he leads a Cellular Neurobiology Group. My scientific vision is to create a molecular map linking electrical input with synaptic chemical output to understand what controls the flow of information in the brain as well as identify potential therapeutic targets for axonal channelopathies and synaptic signaling disorders. Mike earned his B.A. in biology from Reed College in Portland Oregon, and completed his D.Phil in Physiology from the University of Oxford, where he studied electrical signaling in pancreatic islets. He then joined Timothy Ryan’s laboratory at Weill Cornell Medical in New York City to investigate calcium channel trafficking in synaptic terminals and develop quantitative optical approaches to understand the brain.

 

Bryan Luikart, PhD Assistant Professor of Molecular and Systems Biology, Geisel School of Medicine

Title: Uncovering the Neurobiological Basis of Autism with PTEN Genetic Models


Abstract:
Autism Spectrum Disorder (ASD) is a developmental disorder characterized by symptoms such as altered social interaction, restricted communication, and stereotyped behavior. One genetic cause for ASD is mutations in the gene Pten. We have introduced PTEN mutations that have been identified in human patients into the mouse and study how this effect the development and activity of individual neurons in the mouse brain. Understanding the primary effects of Pten mutations on the function of individual neurons will improve our understanding of the dysfunctional autistic brain.  Further, establishing that manipulation of Pten in the mouse can mimic the symptoms of human ASD patients will allow us to test treatments that could cure certain forms of ASD

Bio: Bryan Luikart received a BS in Molecular and Cell Biology from Texas A&M Universty (1999), a PhD in Neuroscience from University of Texas Southwestern Medical Center under Luis Parada (2004), and completed postdoctoral training under Gary Westbrook at the Vollum institute (2010). Dr. Luikart joined the Geisel School of Medicine at Dartmouth in 2011.  Since joining the faculty at Geisel, Dr. Luikart studies how dysfunction of the autism predisposition gene, PTEN, impacts neuronal function.  Further, the Luikart laboratory has continued to develop more sophisticated tools for viral-mediated molecular manipulation with the goal of understanding the neurobiological basis of autism.

 

Allan T. Gulledge, PhD Associate Professor of Molecular & Systems Biology, Geisel School of Medicine at Dartmouth College

Title: Reciprocal control of corticofugal output by serotonin and acetylcholine

Abstract: Pyramidal neurons in the mouse medial prefrontal cortex comprise two broad subclasses of neurons defined by their long-distance axonal projections: intratelencephalic neurons, which include commissural/callosal (COM) projection neurons, and corticofugal neurons, which include those projecting to the pons (CPn neurons). COM and CPn neurons are differentially regulated by modulatory neurotransmitters, including serotonin (5-HT) and acetylcholine (ACh). While CPn neurons are universally inhibited via Gi/o-coupled 5-HT1A (1A) receptors, COM neurons are excited via Gq-coupled 5-HT2A (2A) receptors. Further, although both neuron subpopulations express Gq-coupled M1 muscarinic ACh receptors, ACh preferentially enhances the excitability of CPn neurons. This suggests that 5-HT and ACh may exert opposing influences on corticofugal output to the brainstem. Consistent with this hypothesis, we find that release of endogenous ACh selectively and persistently increase action potential output in CPn neurons (for up to 60 s) through at least two distinct mechanisms, including suppression of M-current and activation of a calcium-permeable conductance. Our findings demonstrate that 5-HT and ACh exert reciprocal control over corticofugal output to the brainstem, suggesting a circuit-based mechanism by which these transmitters may differentially contribute to behavior.

Bio: Allan Gulledge is an Associate Professor in Department of Molecular & Systems Biology. His research is focused on the cellular neurophysiology of the cerebral cortex. He earned his bachelor’s degree in Psychobiology and the University of California at Riverside, and his doctorate in Biology at the University of Texas at San Antonio.  Dr. Gulledge was an NSF International Research Fellow at the Australian National University in Canberra, Australia, and a JSPS Research Fellow at the National Institute of Physiological Sciences in Okazaki, Japan, before joining the faculty of the Department of Physiology at the Geisel School of Medicine in 2007.

 

Geoffrey P. Luke, PhD Assistant Professor of Engineering, Thayer School of Engineering at Dartmouth

Title: Piezoelectric nanoparticles for ultrasound brain interfacing

Abstract: There is a concerted effort in the neuroscience research community to map out the connections in the brain. There is a lack of available tools, however, that can provide high resolution imaging or stimulation of neural activity throughout the entire brain. Ultrasound imaging is well suited to fill this void because it can be tightly focused deep in tissue with high (kHz) temporal resolution. The main drawback, however, is that ultrasound is not inherently sensitive to electrical activity. We are developing neural-targeted piezoelectric barium titanate nanoparticles to enable ultrasound neural interfacing. Piezoelectric nanoparticles convert electrical signals to acoustic energy, and vice versa. This talk will focus on our recent efforts to synthesize molecularly specific nanoparticles and demonstrate their ability to noninvasively trigger neurons and visualize neural activity.

Bio: Geoffrey P. Luke is an Assistant Professor in the Thayer School of Engineering where he leads the Functional and Molecular Imaging Laboratory. His research is focused on developing optical and ultrasound imaging methods and combining them with nanotechnology for cancer and neural applications. He earned his Bachelor’s Degree in Computer Engineering and Mathematics and Master’s Degree in Electrical Engineering from the University of Wyoming. He then completed his PhD in Electrical Engineering at The University of Texas at Austin, where he focused on ultrasound and photoacoustic imaging.

 

Dawei Li, PhD Assistant Professor, Department of Microbiology and Molecular Genetics, University of Vermont

Title: Genome-wide copy number variation analyses identify two deletions associated with alcohol dependence

Abstract: Genome-wide association studies of single nucleotide polymorphisms (SNPs) have yielded associations with addiction to substances. However, all the identified SNPs collectively account for a small proportion of estimated heritable risks for developing the disorders, leaving a mystery of missing heritability in addiction. Converging evidence show that copy number variations (CNVs) contribute to the development of various complex human diseases. We analyzed a total of 6,950 African-Americans and European-Americans of alcohol dependence patients and controls assayed using one million CNV probe arrays. We implemented multiple CNV calling algorithms, and carried out a genome-wide CNV analysis. We found two deletions significantly associated with AD (OR = 7.41 and P = 4×10-15). This talk will focus on this preliminary data.

 

Bio: Dawei Li, is an Assistant Professor at University of Vermont where he leads a Human Genetics and Genomics Laboratory. His research includes (1) identifying structural variations and single-point mutations associated with psychiatric disorders, and (2) identifying viral DNA in the human genome in various human diseases. Dr. Li received his Ph.D. in Biochemistry and Molecular Biology from Shanghai Jiao Tong University, and obtained postdoctoral training in Statistical Genetics at Rockefeller University. He has held a faculty position in psychiatric genetics and genomics at Yale University and joined the UVM faculty in 2012.

 

Luke J. Chang, PhD Assistant Professor, Psychological and Brain Sciences, Dartmouth College

Title: Neural basis of spontaneous impression formation in naturalistic social context

Abstract: A major goal of social and affective neuroscience is to identify systematic mappings between psychological and neural function.  However, standard approaches using controlled experimental designs can decontextualize social and affective psychological processes.  In this study, we sought to understand how people form impressions of individuals and social networks using a naturalistic experimental paradigm.  Participants watched the first episode of a TV drama (Friday Night Lights) and rated their impressions of each character and how they believed characters related to each other.  In analysis 1, we developed multivariate patterns associated with encoding each character’s identity and probed these models to identify regions of the brain involved in encoding multidimensional trait information.  This analysis revealed that the STS, parahippocampus, dACC, and lateral PFC are involved in integrating multiple social dimensions to form an impression about a character.  In analysis 2, we sought to identify regions of the brain involved in encoding how characters relate to each other and form complex social networks.  We found that participants’ perceptions of character relationships were associated with activation dynamics in the TPJ, STS, and PCC, regions previously implicated in reasoning about others’ mental states.  These results provide a compelling proof of concept that brain signals associated with forming social impressions can be identified using naturalistic experimental paradigms.

Bio: Luke Chang, PhD is an Assistant Professor of Psychological and Brain Sciences at Dartmouth College and directs the Computational Social Affective Neuroscience Laboratory. He completed a BA in psychology at Reed College, an MA in psychology at the New School for Social Research, and a PhD in clinical psychology and cognitive neuroscience at the University of Arizona. In addition, Luke completed his predoctoral clinical internship training in behavioral medicine at the University of California Los Angeles and a postdoctoral fellowship at the University of Colorado Boulder in multivariate neuroimaging techniques. His research program is focused on understanding the neurobiological and computational mechanisms underlying emotions and social interactions and his research spans the emerging fields of social, affective, and decision neurosciences.

 


Schedule

8:30am - 8:50am Coffee and Poster Set-up
8:50am - 9:00am Opening Remarks
9:00am - 9:45am Teaser talks: one slide, linked to poster
9:45 am - 11:00 am Poster Session
11:00 am - 12:00 pm Faculty Talks – Part 1
12:00 pm - 1:00pm Lunch
1:00 pm - 2:00 pm Student Talks
2:00 pm - 2:45 pm Career Forum
2:45 pm - 2:55 pm Coffee Break
2:55 pm - 3:55 pm Faculty Talks – Part 2
4:00 pm - 5:00 pm Keynote Lecture: Ann Graybiel, MIT