不可控的意識—以思緒漫遊角度檢驗影響思緒壓抑失敗的因素

Abstract

過去心理學家認為思緖壓抑失敗和思緒漫遊（mind wandering）這兩個意識失控的現象有關，但尚未有實徵研究支持。本論文探討思緒漫遊和思緒壓抑的關係。並從個別差異的角度探討工作記憶廣度與專注當下特質（mindfulness trait）和思緒漫遊傾向以及思緒壓抑表現的關係。本論文以思緖壓抑作業測量思緖壓抑表現，參與者被要求五分鐘內不得想到白熊有關思緖並自我報告壓抑失敗次數，思緖漫遊傾向同樣以自我報告測量之。實驗一探討白日夢傾向(沒有專注目標時的思緒轉換頻率）與思緖壓抑作業表現的相關。結果顯示前者傾向愈高，隨後思緒壓抑失敗的次數也愈高。實驗二以不同的指導策略（專注呼吸或專注於心理物件，例如藍色跑車）操弄參與者在思緒壓抑作業時產生思緒漫遊的程度。如所預期，使用專注呼吸策略時比使用專注心理物件策略有較低的思緒漫遊傾向，也在隨後的思緒壓抑作業中有較好的表現。同時也發現專注呼吸組思緖壓抑失敗次數和專注當下特質呈負相關但與工作記憶廣度無關；而專注心理物件組的思緖壓抑失敗次數則和工作記憶廣度呈負相關而與專注當下特質無關。本研究首次提供了支持思緒漫遊和思壓抑失敗間關係的實徵證據，且顯示個別差異因素與意識失控的關係，並對壓抑策略的適用性有所意涵。

Intrusion of unwanted thoughts (IUTs) is supposed to occur during mind wandering when mental resource is of short. However, few studies, if any, have empirically tested the relation between IUTs and mind wandering. A typical thought suppression paradigm, the white bear task, and mind wandering paradigm were applied to test the relationship between mind wandering and IUTs. In addition, we test the relationships between two individual traits, working memory capacities (WMC) and mindfulness traits and mind wandering or IUTs. In experiment 1, we found participants who have more daydreams (i.e., the frequency of shift in thoughts) at rest were prone to have IUTs. In experiment 2, participants’ tendency toward mind wandering was further reduced to different degrees by instructing them to focus on different targets (participants’ own breathes or a mental object) while doing thought suppression task. It was found that, compared to focus-object group, focusing-breath group, who had fewer mind wandering, did had fewer IUTs. In addition, results showed that relationships between two individuals’ traits and mind wandering or IUTs would change with different focusing targets. In focused-breath group, participants mind wandering and IUTs were negatively correlated with their mindfulness trait but were not correlated with WMC; whereas in focused-object group, their mind wandering and IUTs were negatively correlated with their WMC but were not correlated with their mindfulness trait. This study, for the first time, confirmed the conjectured relationship between mind wandering, both daydreaming and task-unrelated one, and IUTs. It also revealed that participants’ performance on thought suppression task was influenced by individuals’ WMCs and mindfulness traits in an opposite way, depending on the strategy they used to control mind wandering.