動機對主觀認知退化者認知介入療效之影響： 以動手樂活動之先導性研究為例

Abstract

背景：主觀認知衰退（subjective cognitive decline, SCD）為失智症分期中最早出現行為改變的階段，雖其客觀測驗未達認知損傷的程度，但在客觀及主觀認知表現，包含執行功能、記憶力等，與健康長者有差異。然而，影響SCD的認知介入成效者，個體「動機」差異性可能為重要的因子。根據自我決定理論（Self-Determination Theory, SDT），內在動機將有助於正向的表現。過去文獻亦指出，較高的動機與自我效能與較好的認知表現有關，較低的動機及自我效能感，則可能進一步降低介入之成效。然而，現前文獻鮮少探討動機及其相關因子對SCD認知介入成效的影響。 目的：本研究旨在探討動機及相關因子對SCD長者認知介入成效的影響，採用動手樂活動作為執行功能介入方案，探討動機、自我效能感對執行功能成效之影響。 方法：本研究為單一組別前後測實驗設計，共22位社區招募的SCD患者，參與每週兩次，每次2小時，共6週之動手樂團體介入。在介入前、後對所有受試者進行成效評估，包含主要成效（執行功能）及次要成效（整體認知功能、記憶力、注意力、創意、焦慮、憂鬱）。受試者的動機狀態以情境動機量表（內在動機、認同調節、外在調節、無動機）、內在動機量表（興趣/享受、努力、感知選擇、感知能力、價值/實用性、緊張/壓力、關聯性）、一般自我效能感量表量測，於介入前、介入第二周、第四周及第六周共四次時間點收集。組內前後測之差異比較使用威爾卡森符號檢定（Wilcoxon signed-rank test）進行分析並計算效應值（Cohen's d）。以斯皮爾曼等級相關性分析（Spearman rank correlation）檢測影響因子間及其與成效變化的相關性。動機及自我效能感之變化則以簡單線性迴歸（simple linear regression）之斜率表示。最後以多元線性迴歸（multiple linear regression）探索動機及自我效能感對認知介入成效的影響。 結果：以動手樂活動介入SCD患者，在執行功能表現（問題解決能力、認知彈性等）有不同程度之改善，且此改善能以部分動機因子的基線（baseline）及變化（Δ）顯著預測。執行功能中，問題解決能力的進步量由基線「內在動機」負向預測（B = 0.14, p = 0.01），以及「感知選擇」的變化（Δ）負向預測（B = 2.07, p = 0.04）；認知彈性由「價值/實用性」（B = -0.68, p = 0.002）的變化（Δ）正向預測。表示基線內在動機較高，及自主性的提升，預測較少的問題解決能力進步量；而認同調節的上升，預測較多的認知彈性進步量。 結論：本初探研究顯示，社區篩選之SCD患者在以動手樂活動介入後，執行功能成效改善受動機相關因子變化量影響，尤其「認同調節」，意即當SCD長者認同活動的價值、認為對自己有益，將有助於執行功能的改善。然而，「感知選擇」越多，意即當受試者感受到活動自主性越高，可能限制其執行功能介入的成效。本研究辨識顯著的動機影響因子，將可為日後認知介入方案設計提供參考，包含參與者在方案中的自主程度、方案給予參與者的價值是否受到認同等，以促進參與者從中獲得較佳成效。然而，本研究僅為初探研究，樣本數量小，未來仍需加以驗證動機對認知介入成效之影響。

Background: Subjective cognitive decline (SCD) represents the earliest stage of behavioral changes in the dementia continuum. Although individuals with SCD do not meet the criteria for objective cognitive impairment, their cognitive performance—both objective and subjective—such as executive functioning and memory, differs from that of cognitively healthy older adults. Among the various factors influencing the effectiveness of cognitive interventions for individuals with SCD, individual differences in motivation may play a crucial role. According to Self-Determination Theory (SDT), intrinsic motivation contributes to more positive performance outcomes. Previous studies have also shown that higher levels of motivation and self-efficacy are associated with better cognitive performance, while lower levels may undermine the benefits of interventions. However, limited research has explored the impact of motivation and its related factors on cognitive intervention outcomes in individuals with SCD. Objective: This study aimed to investigate how motivation and related factors influence the effectiveness of cognitive interventions in older adults with SCD. We used “Tinkering Activities” as a cognitive intervention program to investigate the influence of motivation and self-efficacy on executive function efficacy. Methods: A single-group pre-post experimental design was employed. 22 individuals with SCD were recruited from the community to participate in a six-week group-based “Tinkering Activities”, conducted twice a week for two hours per session. All participants underwent outcome assessments before and after the intervention, including primary outcomes (executive function) and secondary outcomes (global cognitive function, memory, attention, creativity, anxiety, and depression). Motivational states were measured using the Situational Motivation Scale (assessing intrinsic motivation, identified regulation, external regulation, and amotivation), the Intrinsic Motivation Inventory (assessing interest/enjoyment, effort, perceived choice, perceived competence, value/usefulness, pressure/tension, and relatedness), and the General Self-Efficacy Scale. Motivation was assessed at four time points: baseline (pre-intervention), week 2, week 4, and week 6. The Wilcoxon signed-rank test will be employed to analyze within-group pre-post differences, with effect sizes calculated using Cohen's d. Spearman’s correlation analysis will be used to examine correlations between influencing factors and their relationship with changes in outcomes. Multiple linear regression will be conducted to explore factors influencing the effectiveness of cognitive outcomes. Result: Results show that participants demonstrated varying degrees of improvement in executive function performance, including problem-solving ability and cognitive flexibility. These improvements were significantly predicted by both the baseline levels and changes (Δ) in certain motivational factors. Specifically, problem-solving improvement was negatively predicted by baseline intrinsic motivation (B = 0.14, p = 0.01) and by changes in perceived choice (Δ; B = 2.07, p = 0.04). In contrast, cognitive flexibility improvement was positively predicted by changes in value/usefulness (Δ; B = –0.68, p = 0.002). These findings suggest that individuals with higher baseline intrinsic motivation or increased perceived autonomy may exhibit less improvement in problem-solving, whereas those who experienced an increase in identified regulation (i.e., recognizing the personal value of the activity) showed greater gains in cognitive flexibility. Conclusion: This preliminary study suggests that changes in motivational factors, particularly identified regulation, may play an important role in executive function outcomes following cognitive intervention in community-screened individuals with SCD. When older adults recognize the personal value or usefulness of the activity, executive function improvements—especially in cognitive flexibility—may be enhanced. Conversely, increases in perceived autonomy (i.e., greater sense of choice or self-direction) may potentially limit the effectiveness in improving executive function. Identifying these key motivational predictors can inform the design of future cognitive intervention programs, such as by considering the optimal level of participant autonomy and ensuring that the intervention’s value is clearly conveyed and internalized. However, as this is an exploratory study with a small sample size, further research is necessary to validate the role of motivation in cognitive intervention outcomes.