検索の意図的な制止による能動的忘却：Think/No-Thinkパラダイムの20年

Abstract

検索の意図的な制止は, 記憶を意図的に思い出さないようにする内的過程を指し, Think/No-Think(TNT)パラダイムによって検討されてきた. 本論文ではTNTパラダイムの実験手続きの説明に始まり, TNT研究によって明らかにされた検索の意図的な制止の効果, メカニズム, そして調整要因を網羅的に概観した. また, 思考抑制との相違点をもとに, 検索の意図的な制止が忘却を引き起こす要因についても論じた. 検索の意図的な制止は, 対象の記憶の忘却を引き起こすだけでなく, 記憶のかかわるさまざまな認知プロセス, さらには感情反応にも影響を及ぼす. その背後にある応答的な制御のメカニズムは運動や感情の制御と共通しており, 領域普遍性を有する. 検索の意図的な制止の制御メカニズムに関する大きな進展の一方で, 忘却のメカニズムについては未解明な部分が多いことも明らかとなった. 検索制止を事後効果も含めて包括的に理解することは, 制御メカニズムの領域普遍性を踏まえると, 運動や感情制御がもたらす効果の解明にも寄与し, ひいては認知的制御の統一的な理解に資するに違いない.

Retrieval stopping refers to intentionally stopping the retrieval of memories, which has been investigated with the Think/No-Think (TNT) paradigm. In this article, after introducing the paradigm’s experimental procedure, we review the after-effects, mechanisms, modulatory factors of retrieval stopping. We also discuss the differences between retrieval stopping and thought suppression, highlighting the aspects of retrieval stopping that are critical to forgetting. Retrieval stopping not only induces the forgetting of target memories but it also influences various cognitive processes, including emotional responses that involve memory. It has been assumed that retrieval stopping entails domain-general reactive control functions that are involved in motor control and emotion regulation. However, the mechanisms that underlie forgetting by retrieval stopping remain unclear in contrast to those of retrieval stopping per se. Given the domain-general nature of its control mechanisms, a comprehensive understanding of retrieval stopping and its after-effects can contribute to elucidating the effects of motor control and emotion regulation, and eventually to yielding an integrative framework of cognitive control.