功能性近紅外光譜術應用於經顱紅外光刺激前後之認知功能評估

Abstract

在現今社會中失智症的人口持續攀升，先前研究指出，經顱紅外光刺激(transcranial infrared light stimulation, TILS)應用於人體實驗上，能夠增加專注力與短期記憶，因此，經顱紅外光刺激應用於延緩失智症的治療上極有潛力。當照射適當的近紅外光，光進入大腦產生光生物調節作用(photobiomodulation)，進而產生含氧血紅素(oxygenated hemoglobin, HbO)、缺氧血紅素(deoxygenated hemoglobin, HbR)以及總血紅素(total hemoglobin, HbT)等血液動力學反應，以及氧化態細胞色素c氧化酶吸收變化。 本研究利用功能性近紅外漫反射光譜(Functional Near Infrared Spectroscopy, FNIRS)技術紀錄受測者於刺激前後進行大腦認知測驗中的光譜資訊，並且將蒐集到的光譜，搭配修正比爾-朗伯定律(Modified Beer-Lambert Law, MBLL)分析法，分析大腦吸收物質濃度相對變化方向，觀察六位受測者刺激前後進行認知測驗時的吸收物質濃度相對變化差異，並針對差異性觀察其與認知能力之關聯。最後透過比較刺激前後吸收物質濃度變化差異與前後測驗答題結果、路徑描繪測驗測得反應時間，評估個別受測者之刺激成效。 以實驗結果，在第一階段實驗中的TILS(十分鐘)，將受測者的光衰減變化量分為三種現象，其吸收物質濃度變化結果共同點為含氧血紅素濃度變化上升，其餘缺氧血紅素濃度變化與氧化態細胞色素c氧化酶吸收變化在三種現象中趨勢略微不同，在同個受測者中不同腦區的吸收物質濃度變化反應有不同的結果，在每位受測者中有反應的通道與通道數量也不相同。在大腦認知測驗中前後測比較的吸收物質濃度變化中，大多數在後測中的含氧血紅素濃度變化低於前測，此現象推測為經過長期刺激後大腦思考效率提升。結合答題結果與路徑描繪測驗，在健康受測者中，刺激時間最久的五號受測者，評估結果為進步最多的受測者，而輕微認知障礙受測者的六號受測者，其吸收物質濃度變化也有含氧血紅素濃度變化低於前測的現象但是在答題結果中沒有進步的現象，因此輕微認知障礙受測者推測需要更久的刺激天數才會有明顯的進步成效。

The population of dementia continues to rise in today's society. Previous studies have pointed out that transcranial infrared light stimulation (TILS) can be used in human experiments to increase concentration and short-term memory. Therefore, transcranial infrared light stimulation It has great potential in the treatment of delaying dementia. When irradiated with appropriate near-infrared light, the light enters the brain to produce photobiomodulation, which in turn produces oxygenated hemoglobin (HbO), deoxygenated hemoglobin (HbR), and total hemoglobin (total hemoglobin). , HbT) and other hemodynamic responses, as well as changes in the absorption of oxidized cytochrome c oxidase. In this study, Functional Near Infrared Spectroscopy (FNIRS) technology was used to record the spectral information of subjects in the brain cognitive test before and after stimulation, and the collected spectra were matched with the Modified Beer-Lambert Law (MBLL) Analytical method was used to analyze the relative change direction of the concentration of absorbed substances in the brain, to observe the relative change of the concentration of absorbed substances before and after stimulation of the six subjects during the cognitive test, and to observe the correlation with cognitive ability according to the differences. Finally, the stimulation effect of individual subjects was evaluated by comparing the difference in the concentration of absorbed substances before and after stimulation, the results of the test before and after the test, and the reaction time measured by the Trail Making Test. According to the experimental results, in the TILS (ten minutes) in the first stage of the experiment, the change of light attenuation of the subject is divided into three phenomena. The changes in the concentration of oxygenated heme and the changes in the absorption of oxidized cytochrome c oxidase have slightly different trends in the three phenomena, and the changes in the concentration of absorbed substances in different brain regions in the same subject have different results. The number of channels and the number of channels that are reactive is also different. Among the changes in the concentration of absorbed substances compared before and after the brain cognitive test, most of the changes in the concentration of oxygenated heme in the post-test were lower than those in the pre-test. Combining the answer results and the path delineation test, among the healthy subjects, the No. 5 subject with the longest stimulation time was the subject with the most improvement in the evaluation result, while the No. 6 subject of the mild cognitive impairment subjects, The changes in the concentration of absorbed substances also have the phenomenon that the concentration of oxygenated hemoglobin is lower than that of the pre-test, but there is no improvement in the answering results. Therefore, the subjects with mild cognitive impairment speculate that it will take longer stimulation days to have significant progress. Keywords: Transcranial infrared light stimulation, functional near-infrared diffuse reflectance spectroscopy, modified Beer-Lambert law, changes in cytochrome c oxidase concentration, changes in oxygenated heme concentration, changes in hypoxic heme concentration, brain cognitive function quiz, Trail Making Test