背景與目的：痛覺溫度刺激(noxious thermal stimulation, NTS)對於中風病人上肢功能恢復的療效已被證實，然而肢體不同部位接受刺激後可能誘發大腦動作皮質興奮程度的變化，仍尚未被探究。本研究目的探討比較上肢不同部位接受痛覺溫度刺激對於大腦皮質興奮性的即時效應。方法：共徵召22位年輕健康受試者(21.6±1.4歲)，慣用手上臂和前臂依隨機先後分別接受為時30分鐘之痛覺溫度刺激介入(熱痛溫度：46 ± 1˚C；冷痛溫度7±1 ˚C介入前和介入後分別進行經顱磁刺激(transcranial magnetic stimulation, TMS)施測，以兩側手掌之外展拇短肌為標的肌肉，記錄大腦皮質動作閾值(motor threshold, MT)、動作誘發電位(motor evoked potential, MEP)與動作區域大小(size of cortical motor output map, map size)做為評估大腦皮質興奮性的參數依據。結果：單因子重複測量變異數分析顯示慣用手前臂在接受完痛覺溫度刺激後大腦皮質動作閾值(%)從58.05±11.60降低至53.14±9.21，而動作誘發電位(mV)由0.31±0.45增加至0.68±0.89，動作區域大小(點數)亦由4.78±3.80增至11.05±7.91，這些參數值的改變量皆達統計上顯著差異(p<.01)。然而，上臂部位接受剌激介入前後參數值的改變量，並未達顯著的差異。結論：健康受試者於慣用手前臂比較上臂部位接受30分鐘痛覺溫度刺激後，更可以促使大腦動作皮質興奮性顯著增加》臨床意義：這些先導性研究的結果可以提供痛覺溫度刺激介入臨床患者治療計畫運用的參考。(物理治療2014;39(1):25-31)

Background and Purpose: Effects of noxious thermal stimulation (NTS) on functional recovery in upper limbs of stroke patients are evident, but the changes of cortical excitability after NTS intervention on different parts of the upper extremity are still unknown. This study aimed to investigate the immediate effect of NTS on the arm versus the forearm in healthy individuals. Methods: Twenty-two apparently healthy adults (age: 21.6±1.4 years) received a 30-minute NTS intervention (hot-pain: 46±10C; cold-pain 7±1°C) on dominant arms or forearms with randomized sequences. Transcranial magnetic stimulation parameters including motor threshold (MT)，motor evoked potential (MEP), and size of cortical motor output map (map size) from both hemispheres were assessed with abductor pollicis brevis as the target muscle before and after two separate NTS interventions. Results: One-way repeated measures ANOVA showed that after NTS on the dominant forearm, the MT decreased from 58.05±11.60 to 53.14±9.21% significantly (p<.01), while the MEP and map size both increased significantly from 0.31 ±0.45 to 0.68±0.89 mV (p<.01) and 4.78±3.80 to 11.05+7.91 (numbers) (pc.01), respectively. However, the change scores for NTS on the arms showed no significant difference. Conclusion: This result indicates that the 30-minute NTS applied on the forearm may induce more cortical excitability than that on the arm. Clinical Implications: The preliminary finding can provide the neurophysiological basis of NTS intervention in clinical practice for patients. (FJPT 2014;39(1):25-31)