ICLM Journal Club
This Week
ICLM Young Investigator Lecture Series
Justin Shobe from the Masmanidis lab will be presenting his work. Title: 'The role of corticostriatal circuits in negative occasion setting'
Abstract: In a complex environment individual cues alone often have poor predictive value. However, animals can learn to use multiple cues to resolve situational ambiguity, thereby allowing them to make more informed behavioral responses. For instance, the sight of food triggers an instinctual approach response, but an experienced animal will only proceed in the absence of any innate as well as learned signs of danger. In these situations, it is remarkable how even neutral cues can, through learning, gain powerful inhibitory control over behavior. This is true even when discrete cues are separated in time, clearly indicating that memory processes, such as working memory, can hold onto critical information for later use. Primarily this process has been studied at the behavioral level. Thus, it is unclear how neuronal circuits generate these kinds of inhibitory signals as well as how this information is maintained across time to modulate the recall of subsequent representations that drive specific behavioral outcomes. In order to address these questions, I will discuss our simplified Pavlovian feature negative conditioning paradigm that captures the critical hallmarks of this learning because it is the pattern of temporally separated odors (rather than an individual odor) that predicts the absence of a reward delivery. Specifically, mice learn that a reward follows a single odor presented alone (CS1àR) but if this odor is preceded by a separate cue (CS2) the trial is unrewarded (CS2-CS1àNR). Mice appear to solve this task using an ‘occasion setting’ strategy because we observe that the CS2 feature cue temporarily and specifically modulates the association between the CS1 target cue and reward. Thus, we hypothesize that CS2 initiates a working memory component that selectively gates the ability of the CS1 to trigger reward representations. Consistent with this interpretation, we simultaneously recorded activity in regions that are critical for working memory (the frontal cortex) and reward processing (the striatum) using large-scale multichannel microelectrode arrays (256 channels/region) and found significantly diminished activity during the target CS1 presentation only when it follows the feature cue (CS2). Taken together this suggests that, within cortico-striatal circuits, cue pattern can establish inhibitory gating properties that mediate behavioral responses.
About Us
Introduction
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 Organizers:
Walt Babiec (O'Dell Lab) & Helen Motanis (Buonomano Lab)
Current Faculty Advisor:
Past Organizers:
i) Anna Matynia(Aug 2004 - Jun 2008) (Silva Lab)
ii) Robert Brown (Aug 2008 - Jun 2009) (Balleine Lab)
iii) Balaji Jayaprakash (Aug 2008 - Nov 2011) (Silva Lab)
iv) Justin Shobe & Thomas Rogerson (Dec 2011 - June 2013) (Silva Lab)
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