遺忘可被分為兩種，永久性遺忘以及暫時性遺忘。永久性遺忘代表記憶永遠的 消除，而暫時性遺忘則是暫時性記憶無法提取。暫時性遺忘很常發生在有外在刺激 介入時，且通常此外力不再時，記憶便能夠正常地被提取出來。然而，暫時性提取 障礙的神經生物學機制仍然未知。為了研究短期記憶的暫時性遺忘所涉及的細胞機 制，我們利用古典厭惡制約學習模式來探討其中的迴路。我們使用黑腹果蠅作為動 物模型，並著重於特定的多巴胺神經元 PPL-1 和 PAM，探討兩者在其中所參與的 機制。我的研究發現，當果蠅經過厭惡氣味訓練後暴露於 CS+氣味以及與 naïve 果 蠅社交互動，雖然並不會對原有記憶造成影響，但當遇到電擊刺激時會造成短期記 憶提取的障礙，然而當電擊刺激消失一段時間後，原本的厭惡記憶便能夠再次被提 取出來。
在正常情況下厭惡記憶會激活迴避行為相關的神經迴路，相對地抑制趨向行為 相關的神經迴路，然而我們發現，當訓練後果蠅暴露於 CS+氣味以及與 naïve 果蠅 社交互動後電擊刺激激活了特定與趨向行為相關的神經，包括 MVP2 和 PAM 神 經，這些神經元影響了迴避行為，並成為一種衝突情境，我們認為這是干擾厭惡行 為的因素，並且最後形成暫時性遺忘。總結以上，我們在較不穩定的短期記憶中， 發現了暫時性遺忘的現象，表明了較不穩定的記憶也會有暫時性遺忘發生，且與長 期記憶的暫時性遺忘相同，都是提取功能的障礙。本研究更進一步地提供了新的對 於暫時性遺忘的觀點，可能經由與記憶有衝突性之神經的活化所致。

Recent studies have identified forgetting as either permanent disappear or transient memory blocking. Unused information tends to fade with the passage of time, resulting in permanent forgetting; on the other hand, temporary memory retrieval impairment, triggered by interfering stimuli immediately before memory retrieval, causes transient forgetting. However, the cellular mechanism that produces a temporary state of retrieval failure remained unknown. To investigate the cellular mechanism involves in short-term memory transient forgetting, the classical aversive associative learning paradigm was used to address this issue. We used Drosophila melanogaster as the animal model and focus on specific dopaminergic neurons, PPL-1 and PAM, which are responsible for mediating unconditioned stimulus (US).
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