ICLM Journal Club
This Week - 15 January 2021 (9:30 a.m., via Zoom)
Speaker: Alexander Friedman
Title: “Striosomes Mediate Conflict Decision-Making and Valence-Based Learning, and are Vulnerable in Stress, Aging and Huntington’s Disorder”
Abstract: A striking neurochemical form of compartmentalization has been found in the striatum of humans and other species, dividing it into striosomes and matrix. The function of this organization has been unclear, but the anatomical connections of striosomes indicate their relation to emotion-related brain regions including the medial prefrontal cortex. Here, I will present the first evidence on the specific role of striosomes in approach-avoidance conflict conditions. My work elucidates that chronic stress, aging, and Huntington’s disorder all lead to dysfunction of the cortical-striosomal circuit, causing abnormal decision-making. Also, we found that activity in this circuit is tightly correlated with learning the distinction between cost and reward values, and may encode subjective value. We developed a model that links measured behavior, circuit activity and anatomical connectivity. In brief, the model demonstrates a biologically plausible mechanism by which a reduction in PV inputs to striosomes could be sufficient to provide a mechanism for tuning the excitation-inhibition balance that encodes choice subjective value. Collectively, these findings demonstrate that cognitive and emotion-related functions, like sensory-motor processing, are subject to encoding within compartmentally organized representations in the forebrain. Understanding the cortical-striosomal circuit may lead to the development of new treatments for stress-related disorders and disorders of learning due to aging and neuro-degradation.
Relevant Paper(s): https://www.sciencedirect.com/science/article/abs/pii/S0092867420313015
The Integrative Center for Learning and Memory (ICLM) is a multidisciplinary center of UCLA labs devoted to understanding the neural basis of learning and memory and its disorders. This will require a unified approach across different levels of analysis, including;
1. Elucidating the molecular cellular and systems mechanisms that allow neurons and synapses to undergo the long-term changes that ultimately correspond to 'neural memories'.
2. Understanding how functional dynamics and computations emerge from complex circuits of neurons, and how plasticity governs these processes.
3. Describing the neural systems in which different forms of learning and memory take place, and how these systems interact to ultimately generate behavior and cognition.
History of ICLM
The Integrative Center for Learning and Memory formally LMP started in its current form in 1998, and has served as a platform for many interactions and collaborations within UCLA. A key event organized by the group is the weekly ICLM Journal Club. For more than 10 years, graduate students, postdocs, principal investigators, and invited speakers have presented on topics ranging from the molecular mechanisms of synaptic plasticity, through computational models of learning, to behavior and cognition. Dean Buonomano oversees the ICLM journal club with help of student/post doctoral organizers. For other events organized by ICLM go to http://www.iclm.ucla.edu/Events.html.
Current Faculty Advisor:
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