西蒙轉換作業之編製與信、效度研究

Examining the Reliability and Validity of the Simon Switching Task

西蒙作業測量執行功能，西蒙效應反映刺激與空間關係的抑制效果，而西蒙轉換需認知彈性以應對規則變化。本研究基於Simon（1990）實驗設計，開發平板化西蒙轉換作業，分三階段進行：第一階段熟悉反應規則，第二階段引入空間變項測試西蒙效應，第三階段加入規則轉換以測試認知彈性。本研究共招募1,257名參與者（國小387人、國中281人、高中278人、成人311人），其中42人參與再測信度測試，部分參與者接受其他效標作業。結果發現，西蒙轉換作業的抑制或轉換指標具有內部相關性。年齡分析顯示，抑制與轉換能力隨年齡增長而提升，於高中趨於穩定。信度分析顯示本測驗具有良好再測信度。效度分析中，抑制指標與叫色作業相關（抑制優勢反應），但與側翼作業（抑制外部干擾）無關，顯示效標關聯效度。轉換指標與選擇反應時間及卡片分類的認知彈性相關，顯示效標關聯效度；且與其他抑制測驗無顯著相關，顯示區辨效度。本研究開發平板化西蒙轉換作業，以有效測量抑制與轉換能力，並透過簡便施測提升應用價值，適用於教育與臨床領域，如評估執行功能發展與識別學習障礙風險。然而，平板化測驗可能受背景干擾、操作習慣等因素影響，與傳統測驗的測量差異仍有待進一步探討，以確立其適用範圍與限制。

Executive functions (EFs) refer to the abilities that enable individuals to regulate cognition and behavior to achieve goals and typically include three core components: inhibition, switching, and updating. The purpose of this study is to develop a Simon Switching Task to simultaneously assess two of these core abilities of EFs, thereby increasing the applicability of EF assessments. With the growing popularity of digital learning, tablet-based assessments have gained attention due to their portability and ease of use. Standardized tablet-based tests for fluency and updating abilities are also gradually being developed in Taiwan. Therefore, this study aims to develop a tablet-based version of the Simon Switching Task and examine its reliability and validity.
The Simon Task is a widely used psychological test. It is designed to assess inhibitory function by measuring the effects of spatial congruency and incongruency between stimulus and response locations. When stimulus and response locations are congruent, reaction times are faster; when they are incongruent, reaction times are slower. This phenomenon, known as the Simon effect, reflects the ability to inhibit spatial interference. Although the Simon effect is indicative of an individual’s inhibitory ability, different studies offer different definitions of inhibition. At its core, inhibitory ability involves the suppression of automatic responses in order to maintain goal-directed behavior. The Stroop task assesses whether individuals can suppress automatic responses to the meaning of words when the meaning and color of the words are incongruent. The Simon task assesses whether individuals can inhibit the interference of spatial information when stimulus and response locations are incongruent. Both tasks involve prepotent response inhibition (the suppression of automatic responses). However, the Flanker task is a different process. It primarily assesses the ability to inhibit interference from distracting stimuli adjacent to the target, which is classified as resistance to distractor interference (the suppression of external distractions).
Conversely, the integration of rule-switching into the Simon Task gives rise to the Simon Switching Task, which can assess an individual’s capacity for rule-switching in the face of changes. The Simon Switching Task reveals a close relationship between the shifting process (cognitive flexibility) and processing speed. In this context, processing speed is defined as the time required by an individual to complete cognitive tasks, encompassing both simple reaction time and choice reaction time. The Simon Switching Task demands that individuals swiftly adjust their response strategies and inhibit non-target rules when rules change, a process analogous to the cognitive processing involved in choice reaction time. The Wisconsin Card Sorting Test is a widely employed tool for measuring cognitive flexibility, wherein participants are required to swiftly adapt to novel rules following a rule change. Individuals with high cognitive flexibility can adapt more expeditiously to new rules and are less influenced by prior rules.
This study recruited a total of 1,257 participants, including 387 elementary school students, 281 junior high school students, 278 senior high school students, and 311 adults. Among them, 42 participants took part in the test-retest reliability assessment. The tests were conducted using Lenovo tablet computers, and the Simon Switching Task was developed with Unity. The Simon Switching Task consisted of three stages. Stage 1 was to get the participants familiar with the rules, and they had to respond based only on color cues. Stage 2 introduced spatial location as a variable, with stimuli appearing on either the left or right side of the screen to assess inhibition (the Simon effect). When the stimulus location matched the response key location, it was considered a congruent condition; when they did not match, it was considered an incongruent condition. Stage 3 introduced rule-switching to assess shifting ability (cognitive flexibility). When the rules were the same as in stages 1 and 2, it was considered a non-switch condition; when the rules changed, it was a switch condition. The“inhibition time”indicator reflected inhibition performance and was calculated by subtracting the reaction time in the congruent condition of stage 2 from the reaction time in the incongruent condition of stage 2. A larger value indicated poorer inhibition ability. The“shifting time”indicator reflected shifting performance and was calculated by subtracting the reaction time in the non-switch condition of stage 3 from the reaction time in the switch condition of stage 3. A larger value indicated poorer shifting ability.
The results showed that inhibition time and shifting time were not significantly correlated, supporting the view that they operate as independent mechanisms. The inhibition performance of elementary school students was poorer than that of junior high, senior high school students, and adults, indicating that inhibition ability gradually improves with age. Shifting performance also improved with age; elementary school students performed worse than senior high school students, and junior high school students performed worse than senior high school students and adults. This suggests that cognitive flexibility develops with age and that both inhibition and shifting abilities gradually enhance and stabilize by the senior high school stage. In the validity analysis, inhibition performance was significantly positively correlated with inhibition performance on the Stroop Task but not with that on the Flanker Task. This suggests that the inhibition process in the Simon Task aligns with prepotent response inhibition rather than resistance to distractor interference. Meanwhile, shifting performance was associated with processing speed and the cognitive flexibility assessed by the Sorting Test. For test-retest reliability, a follow-up test was conducted six months later with 42 participants. The results indicated that the Simon Switching Task demonstrated stable test-retest reliability.
The results support the executive function model proposed by Miyake et al., which suggests that inhibition and switching operate as independent mechanisms. The inhibition process in the Simon Task aligns with prepotent response inhibition, but differs from the resistance to distractor interference. Meanwhile, the switching process was significantly correlated with cognitive flexibility and selective processing speed, indicating that the shifting indicator in the Simon Switching Task effectively measured. However, the relatively small test-retest reliability sample size in this study suggests the need for a larger sample in future research for further validation. The touch sensitivity of tablets might influence reaction times, highlighting the need to examine measurement differences across different devices. Furthermore, cultural or linguistic differences might affect the generalizability of the test results, suggesting that cross-cultural comparisons should be considered in future studies.
This study developed a tablet-based Simon Switching Task and confirmed its reliability and validity, demonstrating that it can effectively assess both inhibition and shifting abilities. Tablet-based assessments offer several clear advantages. Firstly, they provide greater flexibility in testing. Compared to traditional computers, tablets are more portable, making them suitable for assessments in various settings. Secondly, they enhance data collection accuracy. The touch screens on tablets can precisely record reaction times and touch trajectories, improving the precision of data analysis. Additionally, the user interface of tablet-based tests is simple and intuitive, reducing the difficulty for participants, particularly for children and older adults. It can assess executive functions in patients with attention-deficit/hyperactivity disorder (ADHD), autism spectrum disorder (ASD), and other neurodevelopmental disorders. Finally, the test can be utilized as a standardized assessment for longitudinal studies to track cognitive development and decline across different age groups. The tablet-based Simon Switching Task not only enhances the applicability of executive function assessments but it is expected to offer practical utility in an even wider range of fields.