唐氏症視知覺功能與電腦化視知覺訓練方案成效探討：功能性磁振造影研究

Investigation of visual perception functions and the effects of a Computerized Visual Perceptual Training program in Down syndrome: A functional MRI study

萬羿廷(Yi-Ting Wan)

指導教授 ： 汪宜霈

共同指導教授 ： 陳佳如(Chia-Ju Chen)

高雄醫學大學/健康科學院/職能治療學系碩士班/碩士(2015年)

https://doi.org/10.6832/KMU.2015.00097

摘要

背景：本研究主要目的為：（一）利用功能性磁振造影(fMRI)與視知覺能力測驗－第三版（TVPS-3）探討唐氏症（DS）之視知覺功能。（二）探討自行設計之「電腦化視知覺訓練方案」(CVPT)於增進DS視知覺功能之介入成效。

方法：接受TVPS-3評估之受試者共有180位，包括70位DS、70位正常發展個案(TD)與40位非特異性智能障礙(ID)。再從70位DS中挑選38位受試者參與後續CVPT療效研究，包括18位DS實驗組（接受CVPT介入），與20位DS控制組（無接受任何視知覺介入方案）。CVPT介入方案內容包括三種電腦軟體，介入頻率為每週60分鐘、每周一次，為期一年。
在fMRI研究部份，fMRI掃描包括兩項視知覺任務：視覺組織任務(T-HVOT)及完整圖片配對任務(FPMT)。共有39位個案（18位DS實驗組、21位TD組）於CVPT介入前參與fMRI掃描，藉以分離出與視知覺能力相關之神經網絡，並比較兩組個案皮質活化形態之差異。在CVPT介入後，18位DS實驗組同時接受TVPS-3評估視知覺功能改變量，及fMRI掃描以檢視與視知覺能力相關之大腦皮質活化形態之變化；20位DS控制組僅接受TVPS-3評估。

結果：（一）TVPS-3評估結果：與TD組相較，DS在視知覺各向度皆有顯著缺損，但與ID組相較時則無顯著差異。（二）fMRI反應表現：與TD組相較，DS組正確率較低且反應時間也較長(p < 0.05)。(三) fMRI掃描結果：DS組顯示與視知覺相關之神經網絡異常，缺乏顯著活化腹側流(枕中迴與顳下迴)、背側流(右側頂葉)與腹外側前額葉皮質(VLPFC)等區域，這些區域被認為與視覺區辨、空間轉換能力與物體工作記憶有關。本研究也建立TD組與視知覺相關之神經網絡。（四）CVPT成效探討：在完成一年CVPT介入後，DS實驗組在TVPS-3各分測驗與總分皆有顯著提升(p’s < 0.05)，而DS控制組則無。fMRI答題反應顯示DS實驗組在T-HVOT任務的正確率有顯著進步，且fMRI腦功能結果也指出DS在空間操作相關腦區(上、下頂葉)、與動作想像相關區域(中央前迴與背側前運動皮質區)皆有顯著活化。

結論：本論文為第一個利用fMRI探討DS視知覺功能相關神經網絡之研究，多數研究認為視知覺功能為DS之相對優勢能力，本研究結果顯示DS在視知覺功能確有缺損。CVPT介入能有效提升DS視知覺功能，可提供職能治療師臨床應用之參考。

關鍵字

唐氏症 ； 視知覺 ； 功能性磁振造影 ； 電腦化視知覺訓練方案

並列摘要

Background: The primary purpose of this study was to investigate the visual perceptual functions measured by functional MRI (fMRI) and the Test of Visual Perceptual Skill- Third Edition (TVPS-3) in Down syndrome (DS). A second purpose was to develop a Computerized Visual Perception Training (CVPT) program and further examine the effectiveness on improving visual perceptual functions in DS.

Methods: One hundred and eighty participants ( 70 DS, 70 typically developing individuals [TD], and 40 with unspecified intellectual disabilities [ID]) were recruited for the TVPS-3 assessment session. Eighteen DS (experimental group) from the assessment session participated in the CVPT program, and the control group comprised another 20 DS receiving no treatment. The one-year CVPT program consisted of three main computerized programs and was administered once a week, 60 minutes per session.
Functional MRI tasks included two visual perception tasks: two-choice version of Hooper visual organization task (T-HVOT) and full picture matching test (FPMT). Before the implementation of the CVPT, 21 TD group and 18 DS experimental group participated in fMRI study to compare their differences in brain activation areas related to visual perceptual abilities. After one-year CVPT intervention, the DS experimental group was assessed by both TVPS-3 and fMRI to explore the difference in visual perception function and their cortical activation patterns. The DS control group was re-assessed by TVPS-3 only.

Results: (1) TVPS-3 results: DS had deficits in all dimensions of visual perception compared to the TD group. There was no significant difference on TVPS-3 between the DS and ID groups. (2) fMRI behavior results: DS had lower correct response rate (CRR) and higher reaction time than the TD group. (3) fMRI image results: The DS group had abnormal neural network related to visual perceptual abilities. In contrast with the TD group, DS demonstrated no significant activation in the ventral stream (middle occipital gyrus and inferior temporal gyrus), dorsal stream (right parietal lobe), and ventrolateral prefrontal cortex (VLPFC) which are responsible for visual discrimination, spatial transformation and visual object working memory respectively. Neural network correlating of visual perception in TD group was established as well. (4)The effectiveness of CVPT: The DS experimental group had significant improvements in all TVPS-3 subtests and total score (p’s < 0.05) after the one-year CVPT intervention. The CRR of fMRI T-HVOT task was significantly improved in the DS group. As well, the fMRI results indicated more activation in superior, inferior parietal lobe (spatial manipulation), precentral gyrus and dorsal premotor area (motor imaginery) in DS after the intervention.

Conclusion: The findings add to recent investigations into the visual perceptual functions in DS. The CVPT program demonstrated benefit in improving visual perceptual functions in DS. Implications for clinical professionals and recommendations for further research are discussed.

並列關鍵字

Down syndrome ； visual perception ； fMRI ； computerized visual perception training program

參考文獻

一、 中文部份

朱經明(2002)。學習障礙、聽覺障礙及自閉症學生學習3D電腦動畫及影像剪輯

手語歌成效之研究。國立台中師院特教叢書9103輯，15-27。

二、英文部份

Abbeduto, L., Warren, S. F., & Conners, F. A. (2007). Language development in Down syndrome: From the prelinguistic period to the acquisition of literacy. Mental Retardation and Developmental Disabilities Research Reviews, 13, 247-261.