Dopamine Neurons Mediate Learning and Forgetting through Bidirectional Modulation of a Memory Trace

By Jacob A. Berry, Anna Phan, Ronald L. Davis. 2018

105 citations recorded by the source corpus.

SUMMARY It remains unclear how memory engrams are altered by experience, such as new learning, to cause forgetting. Here, we report that short-term aversive memory in Drosophila is encoded by and retrieved from the mushroom body output neuron MBOn-γ2αʹ1. Pairing an odor with aversive electric shock creates a robust depression in the calcium response of MBOn-γ2αʹ1 and increases avoidance to the paired odor. Electric shock after learning, which activates the cognate dopamine neuron DAn-γ2αʹ1, restores the response properties of MBOn-γ2αʹ1 and causes behavioral forgetting. Conditioning with a second odor restores the responses of MBOn-γ2αʹ1 to a previously learned odor while depressing responses to the newly learned odor, showing that learning and forgetting can occur simultaneously. Moreover, optogenetic activation of DAn-γ2αʹ1 is sufficient for the bidirectional modulation of MBOn-γ2αʹ1 response properties. Thus, a single DAn can drive both learning and forgetting by bidirectionally modulating a cellular memory trace.

Subfields: Cellular and Molecular Neuroscience, Ecology, Genetics

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Cellular and Molecular Neuroscience

1. Qian Li
2. Yi Zhong
3. Liyuan Wang
4. Raphael Cohn
5. Ianessa Morantte
6. V. Ruta
7. Jun Zhu
8. Xingxing Zhang

In Ecology

1. Liyuan Wang
2. Glenn C. Turner
3. Raphael Cohn
4. Ianessa Morantte
5. V. Ruta

In Genetics

1. Raphael Cohn
2. Ianessa Morantte
3. V. Ruta
4. M. Modi
5. Yichun Shuai
6. Liyuan Wang
7. Jun Zhu
8. Yi Zhong

Citations in the corpus

• Incorporating neuro-inspired adaptability for continual learning in artificial intelligence (2023, positive): “In this case, the forgetting rates serve to diversify these learners, similar to the neurological strategy of decaying old memories differentially in each compartment 24,36–39 .”
• Distinct dopamine receptor pathways underlie the temporal sensitivity of associative learning (2019, background): “While stronger or more prolonged dopamine release in the absence of an odor has been shown to potentiate KC-MBON signaling (Berry et al., 2018; Cohn et al., 2015), extending the interval between KC and DAN stimulation to 6 s resulted inminimal plasticity (Figure 2D).”
• The Drosophila Mushroom Body: From Architecture to Algorithm in a Learning Circuit. (2020, background): “The plasticity induced in one compartment does not spill over to neighboring compartments (Hige et al. 2015a), and the evoked second messenger signals are largely confined to the region of DAN activation (Boto et al. 2014,Handler et al. 2019).”