Distinct dopamine neurons mediate reward signals for short- and long-term memories

Drosophila melanogaster can acquire a stable appetitive olfactory memory when the presentation of a sugar reward and an odor are paired. However, the neuronal mechanisms by which a single training induces long-term memory are poorly understood. Here we show that two distinct subsets of dopamine neurons in the fly brain signal reward for short-term (STM) and long-term memories (LTM). One subset induces memory that decays within several hours, whereas the other induces memory that gradually develops after training. They convey reward signals to spatially segregated synaptic domains of the mushroom body (MB), a potential site for convergence. Furthermore, we identified a single type of dopamine neuron that conveys the reward signal to restricted subdomains of the mushroom body lobes and induces long-term memory. Constant appetitive memory retention after a single training session thus comprises two memory components triggered by distinct dopamine neurons.

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Systematic functional characterization of the intellectual disability-associated SWI/SNF complex reveals distinct roles for the BAP and PBAP complexes in post-mitotic memory forming neurons of the Drosophila mushroom body

10.1101/408500 ◽

2018 ◽

Cited By ~ 1

Author(s):

Melissa C. Chubak ◽

Max H. Stone ◽

Nicholas Raun ◽

Shelby L. Rice ◽

Mohammed Sarikahya ◽

...

Keyword(s):

Intellectual Disability ◽

Mushroom Body ◽

Functional Characterization ◽

Long Term Memory ◽

Term Memory ◽

Functional Understanding ◽

Short And Long Term ◽

Cellular Components

AbstractTechnology has led to rapid progress in the identification of genes involved in neurodevelopmental disorders like intellectual disability (ID), but our functional understanding of the causative genes is lagging. Here, we show that the SWI/SNF chromatin remodeling complex is one of the most overrepresented cellular components disrupted in ID. We systematically investigated the role of individual subunits of this large protein complex in post-mitotic memory forming neurons of the Drosophila mushroom body (MB). Using this approach, we have identified novel differential roles for the two prominent conformations of the Drosophila SWI/SNF complex, known as BAP and PBAP. The PBAP conformation is required post-mitotically for remodeling of the MB γ neurons during morphogenesis and is essential for both short and long-term memory. In contrast, the BAP conformation appears to preferentially effect long-term memory and is associated with γ neuron survival. Our results suggest that different subunits of the SWI/SNF complex may influence learning and memory through diverse and distinct roles in regulating structural plasticity, survival, and functionality of post-mitotic neurons. This study provides novel insight into the neuronal function of individual SWI/SNF subunits and will serve as a basis for understanding SWI/SNF-mediated gene regulatory mechanisms in post-mitotic neurons.

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Multiple Memory Processes Following Training That a Food Is Inedible in Aplysia

Learning & Memory ◽

10.1101/lm.5.3.204 ◽

1998 ◽

Vol 5 (3) ◽

pp. 204-219 ◽

Cited By ~ 6

Author(s):

Dina Botzer ◽

Silvia Markovich ◽

Abraham J. Susswein

Keyword(s):

Short Term Memory ◽

Training Session ◽

Long Term Memory ◽

Training Procedure ◽

Short Term ◽

Training Experience ◽

Term Memory ◽

Memory Processes ◽

Short And Long Term

In many organisms, memory after training can be separated into a number of processes. We now report that separable memory processes are also initiated by a training procedure affectingAplysia feeding behavior, a model system for examining the neural mechanisms underlying the regulation of a complex behavior. Four distinct memory process were identified: (1) a very short-term memory that declines within 15 min, (2) a short-term memory that persists for 0.5–1.0 hr, (3) an intermediate-term memory, observed 4 hr after training, and (4) a long-term memory that is seen only after a 12- to 24-hr delay. The four memory processes can be distinguished by the different training procedures that are required to elicit them. A single 5-min training session is sufficient to elicit the very short-term memory. However, a longer training session that continues until the animal stops responding to food is needed to elicit short-term memory. Intermediate-term memory is observed only after a spaced training procedure (three 5-min training sessions separated by 30-min intervals). A single 5-min training session that does not cause either short-term or intermediate-term memory is sufficient to induce long-term memory, indicating that short- and long-term memory are independent, parallel processes. Short- and long-term memory can also be separated by the effects of a post-training experience. Long-term, but not short-term, memory can be attenuated by cooling animals immediately after training. Cooling before the training does not affect either the training or the subsequent short- or long-term memory.

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Animations Are Dynamic, Effective Tools For Science Teaching: If You Just Follow The Rules!

Journal of College Teaching & Learning (TLC) ◽

10.19030/tlc.v7i12.953 ◽

2010 ◽

Vol 7 (12) ◽

Author(s):

Danton H. O'Day

Keyword(s):

Future Research ◽

Long Term Memory ◽

Original Research ◽

Memory Retention ◽

Term Memory ◽

Dynamic Events ◽

Complementary Resources ◽

Short And Long Term ◽

Males And Females

Textbook companies are increasingly including larger numbers of animations as complementary resources for students and teachers. Are all animations useful as teaching tools? The answer is no. Animations can be useful for communicating dynamic events and processes but only when specific rules are followed. The authors review the important components of effective animations and their extensive, original research on the value of animations in learning and long-term memory retention. When the rules are applied, students can learn complex material more easily and retain more of what they have learned in short and long term memory than they can by viewing static textbook figures. Our results also indicate that learning from animations and graphics differs between males and females. Insight gained from student feedback is highlighted with some final comments on future research.

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