Past Events

Joshua I Gold, PhD

Complexity and optimality in adaptive decision-making

January 15, 2019 4:00 pm - 5:00 pm

Greene Science Center, 9th Floor, 3227 Broadway, New York

Our brain uses past experiences, integrated over multiple timescales, to shape how it makes decisions in our uncertain and dynamic world. These adaptive processes can take many forms, across both conditions and individuals, with different combinations of costs (like processing time) and benefits (like flexibility) that can make them difficult to compare and benchmark. Here I will describe our recent efforts to characterize the effectiveness of decision processes with respect to the complexity of model they use to convert past observations into useful predictions that can guide choices. I will show that this approach: 1) has a solid theoretical foundation using concepts drawn from physics and other fields; 2) can account for substantial individual variability of human subjects performing certain decision tasks; and 3) leads to quantitative predictions about the most efficient and effective solutions to a host of decision problems according to a fundamental “law of diminishing returns” relating accuracy to complexity. I will then show that these notions of complexity can be encoded in pupil-linked arousal systems that, in turn, may reflect the influence of neuromodulatory systems like the locus coeruleus-norepinephrine system on coordinated neural dynamics that can affect how information is integrated over time.

Robert Desimone, PhD

Rhythmic saccadic sampling during feature and spatial attention

January 8, 2019 4:00 pm - 5:00 pm

The Screening Room, 2nd floor, Lenfest Center for the Arts, 615 W 129th Street

Adan Horta (Laboratory of Stavros Lomvardas)

Cell type-specific interchromosomal interactions as a mechanism for transcriptional diversity

December 21, 2018 3:00 pm - 4:00 pm

Jerome L. Greene Science Center, JLG-L8-084

Thesis Defense Seminar

Clare Howard (Laboratory of Richard Mann)

Serotonergic Neurons Modulate Drosophila Walking Speed

December 20, 2018 10:00 am - 11:00 am

Jerome L. Greene Science Center, Lecture Hall - L7-119, 3227 Broadway, New York

Thesis Defense Seminar

Christian Lüscher, MD, PhD

A circuit model of social transmission of food preference

December 18, 2018 4:00 pm - 5:00 pm

Greene Science Center, 9th Floor, 3227 Broadway, New York

Exposure to odors emanating from a conspecific can influence the food choice, a phenomenon called social transmission of food preference (STFP). The piriform cortex codes olfactory perceptions, while the inactivation of neurons in the nucleus accumbens triggers consumption. The neural circuit and cellular substrate of this transition from olfactory perception to value-based action however remains elusive. Here we provide evidence for synaptic plasticity in the mPFC driving the food preference.

Joshua Chalif (Laboratory of George Mentis)

Ventral Spinocerebellar Tract Neurons are Essential for Mammalian Locomotion

December 17, 2018 2:00 pm - 3:00 pm

Todd Amphitheater, P&S 16-405, 630 West 168th Street

Samaher Fageiry (Mentor: Thomas Jessell; Sponsors: Co-Directors, Graduate Program in Neurobiology and Behavior)

Mapping Cortical Connections with Spinal Circuits

December 13, 2018 3:00 pm - 4:00 pm

Jerome L. Greene Science Center, 3227 Broadway, L7-119

Thesis Defense Seminar

Nina So (Laboratory of Sarah Woolley)

Behavioral Significance and Neural Processing of Communication Vocalizations

December 10, 2018 6:30 pm - December 10, 2018 7:00 pm

Jerome L. Greene Science Center, Lecture Hall - L8-084, 3227 Broadway, New York

Thesis Defense Seminar

Yukiko Goda, PhD

Regulating synaptic strength diversity in hippocampal neurons

December 10, 2018 4:00 pm - 5:00 pm

Greene Science Center, 9th Floor, 3227 Broadway, New York

Synapses are the fundamental nodes of information transmission in the brain. The efficacy of synaptic transmission, called synaptic strength and its use-dependent changes are crucial for how the brain perceives the environment, learns and stores memories. The highly diverse synaptic strengths found in a given connection at a particular moment in the hippocampal circuit may therefore reflect varied information coding and on-going learning associated with hippocampal-dependent tasks. However, the cellular and molecular basis by which synaptic strength diversity arises, that is, how synaptic strengths are set and controlled across a synapse population remain to be clarified. We have addressed this question by examining the interaction between multiple synapses of hippocampal neurons using a combination of electrophysiology and imaging approaches. We provide evidence for a novel cellular mechanism involving glial cells in regulating the heterogeneity of synaptic strengths across inputs received by single hippocampal neurons. Our findings underscore the role for glia in orchestrating synaptic transmission properties across a synapse population.

Iain D. Couzin, PhD

Collective Sensing and Decision-Making in Animal Groups: From Fish Schools to Primate Societies

December 4, 2018 4:00 pm - 5:00 pm

Greene Science Center, 9th Floor, 3227 Broadway, New York

Understanding how social influence shapes biological processes is a central challenge in contemporary science, essential for achieving progress in a variety of fields ranging from the organization and evolution of coordinated collective action among neurons, or animals, to the dynamics of information exchange in human societies. Using an integrated experimental and theoretical approach I will address how, and why, animals exhibit highly-coordinated collective behavior, and what this can teach us about information processing more generally. I will demonstrate new imaging and immersive virtual reality technology that allows us to reconstruct (automatically) the dynamic, time-varying sensory networks by which social influence propagates in groups. This allows us to identify, for any instant in time, the most socially-influential individuals, and to predict the magnitude of complex behavioral cascades within groups before they actually occur. By investigating the coupling between spatial and information dynamics in groups we reveal that emergent problem solving is the predominant mechanism by which mobile groups sense, and respond to complex environmental gradients. I will also reveal the critical role uninformed, or unbiased, individuals play in effecting fast and democratic consensus decision-making in collectives, and will validate these predictions with experiments involving schooling fish and wild baboons. These results are shown to transcend specific systems, and may give new insights into how individual brains come to decisions, a hypothesis I will propose, and explore (preliminarily), with ongoing experiments of individual decision-making in immersive virtual environments.