SPRING
2020
The Friedman Brain Institute
C Task-relev
A Schematic of PINned network of delayed paired association B Example firing rates Plastic synapses
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D Normalized Schematic of a simulated neural network for implementing working memory. Rajandata et al., Neuron, 2016 firing rates extracted from PPC 1
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Neurons, sorted
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Building Predictive Models of Brain Health and Disease
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Neurons, sorted
The past few decades have seen a revolution in how we study the The laboratory of Kanaka Rajan, PhD, who joined Mount Sinai two brain. It was not long ago when we first observed the activity of dozens years ago from Princeton University, has been at the forefront of of neurons at a time in a single part of the brain of an awake, behaving developing predictive computational models to understand how animal. Now, we can record the activity of many hundreds, even neurons, ensembles of neurons, and whole brain areas interact thousands, of neurons simultaneously across many different brain areas during cognition and emotion. With these models, the Rajan while memories are being formed or emotions experienced, allowing laboratory has determined how neural circuits become dysfunctional us to understand the brain in normal function, what goes wrong when in anhedonic-like states, providing unique insight into the basis 226 226 it fails in psychiatric and neurological disorders, and potentially how of depression. Leftbe trial, Left preferring Left preferring Left trial, Left preferring Right trial, Lef these flaws might corrected. However, making senseRight of all oftrial, this data 1 1 (petabytes) requires a completely new approach to how we study the Another innovative use of computational neuroscience is to brain, an effort known as computational neuroscience. understand how circuits in the brain support decision-making. Erin Rich, MD, PhD, who received both degrees from Mount Sinai before Today, our scientists are able to use machine learning strategies to completing a postdoctoral fellowship at UC Berkeley, uses state-ofanalyze the immense data from their neuroscience experiments and the-art neurophysiology methods to record the activity of hundreds then build models that can be used to make predictions about how of neurons in the prefrontal cortex while monkeys make preferencethe brain works in both health and disease. Some of this work is being based decisions. Computational techniques predict which options will carried out under the auspices of Mount Sinai’s new Lipschultz Center be chosen based on neural activity, allowing Dr. Rich and her team to for Cognitive Neuroscience. study the evolution of a decision with millisecond-level precision.
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