Ⅴ 考察
眼球運動課題の遂行には、頭頂連合野、前頭眼野などの皮質領域が関与していることが知られている（Terao et al., 1998[20]；Schall & Thompson, 1999[17]; Nobre et al.,2000[13]）。その中でもVGSの遂行能力は正常者において極めて安定しており、ごくわずかな電磁波の影響も検出しうることが予想された。
実際には、電磁波ばく露前後で潜時、振幅、速度などすべての眼球運動のパラメータに有意な変化を認めず、少なくともこの課題の遂行能力に関する限り、電磁波のばく露の影響はないと考えられた。
即ち、この課題の遂行にかかわる視覚野、頭頂連合野、前頭眼野の機能に対して電磁波の影響がなかったと推定できる。
電話より発生する電磁波が注意に促進的な影響を与えるとする報告があるが（Preeceet al., 1999[14]；Koivisto et al., 2000[8]；Lee et al., 2001[10]）、今回の実験では、注意と密接な関係にある眼球運動において電磁波の影響を認めなかった。
今後はさらに電磁波の影響に敏感な眼球運動課題を開発し、これによってごく微弱な変化をとらえることができるか検討する必要があると思われる。
Ⅵ 結論
30分間の携帯電話からの電磁波ばく露は、視覚野・頭頂連合野・前頭眼野等の様々な皮質領域が関与し、注意とも密接な関係のある眼球運動課題（視覚誘導性サッカード課題）に影響しない。
以上が今年度の我々の研究のまとめである。
図1 visually guided saccade の説明
文献
1. Arai N, Enomoto H, Okabe S, Yuasa K, Kamimura Y, Ugawa Y. Thirty minutes
mobile phone use has no short-term adverse effects on central auditory
pathways. Clin Neurophysiol 2003; 114:1390-4.
2. Borbely AA, Huber R, Graf T, Fuchs B, Gallmann E, Achermann P. Pulsed
high-frequency electromagnetic field affects human sleep and sleep
electroencaphalogram. Neurosci Lett 1999: 175; 207-210.
3. Croft RJ, Chandler JS, Burgess AP, Barry RJ, Williams JD, Clarke AR. Acute
mobile phone operation affects neural function in humans. Clin Neurophysiol
2002; 113: 1623-1632.
4. Eulitz C, Ullsperger P, Gabriele F, Elbert T. Mobile phones modulate response
patterns of human brain activity. Neuroreport 1998; 9: 3229–3232.
5. Freude G, Ullsperger P, Eggert S, Ruppe I. Effects of microwaves emitted by
cellular phones on human slow brain potentials. Bioelectromag 1998; 19:
384-387.
6. Hamblin DL, Wood AW. Croft RJ, Stough C. Examing the effects of
electromagnetic fields emitted by GSM mobile phone on buman event related
potentials and performance during an auditory task. Clin Neurophysiol 2004;
115: 171-178.
7. Huber R, Graf T, Cote KA, Wittmann L, Gallmann E, Matter D, Schuderer J,
Kuster N, Borbely AA, Achermann P. Exposure to pulsed high-frequency
electromagnetic field during waking affects human sleep EEG. NeuroReport
2000; 11: 3321-3325.
8. Koivisto M, Revonusuo A, Krause C, Haarala C, Sillanmaki L, Laine M,
Hamalainen. Effects of 902 Mhz electromagnetic field emitted by cellular
telephones on response times in humans. NeuroReport 2000; 11: 413-415.
9. Krause CM, Sillanmaki L, Koivisto M, Haggqvist A, Saarela C, Revonsuo A,
Laine M, Hamalainen H. Effects of electromagnetic fields emitted by cellular
phones on the electroencephalogram during a visual working memory task.
Int J Radiat Biol 2000; 76: 1659-67.
10. Lee TM, Ho SM, Tsang LY, Yang SH, Li LS, Chan CC, Yang SY. Effect on
human attention of exposure to the electromagnetic field emitted by mobile
phones. Neuroreport 2001; 12: 729-31.
83
11. Lee TM, Lam PK, Yee LT, Chan CC. The effect of the duration of exposure to
the electromagnetic field emitted by mobile phones on human attention.
Neuroreport. 2003 Jul 18;14(10):1361-4.
12. Liversedge SP, Findlay JM. Saccadic eye movements and cognition. Trends
Cogni Sci 2000; 4: 6-14.
13. Nobre AC, Gitelman DR, Dias AC, Mesulam MM. Covert visual spatial
orienting and saccades: overlapping neural systems. Neuroimage 2000; 11:
210-216.
14. Preece AW, Iwi G, Davies-Smith A, Wesnes S, Butler S, Lim E, Varey A. Effects
of a 915-MHz simulated mobile phone signal on cognitive function in man. Int
J Radiat Biol 1999; 75: 447-456.
15. Reiser HP, Dimpfel W, Schober F. The influence of electromagneric field on
human brain activity. Eur J Med Res 1995; 1: 27-32.
16. Sandstrom M, Wielen J, Oftedal G, Mild H. Mobile phone use and subjective
symptoms. Comparison of symptoms experienced by users of analogue and
digital mobile phones. Occup Med 2001; 51: 25-35.
17. Schall JD, Thompson KG. Neural selection and control of visually guided eye
movements.
Annu Rev Neurosci 1999; 22: 241-59.
18. Sienkiewicz Z, Jones N, Bottomley A. Neurobehavioral effects of
electromagnetic fields. Bioelectromagnetics 2005; Suppl. 7: S116-S126.
19. Terao Y, Furubayashi T, Okabe S, Arai N, Mochizuki H, Kobayashi S, Yumoto M,
Nishikawa M, Iwata NK, Ugawa Y. Interhemispheric transmission of
visuomotor information for motor implementation. Cereb Cortex 2005; 15:
1025-36.
20. Terao Y, Fukuda H, Ugawa Y, Hikosaka O, Hanajima R, Furubayashi T, Sakai
K, Miyauchi S, Sasaki Y, Kanazawa I. Visualization of the information flow
through human oculomotor cortical regions by transcranial magnetic
stimulation. J Neurophysiol 1998; 80: 936-46.
21. Yuasa K, Arai N, Okabe S, Tarusawa Y, Nojima T, Hanajima R, Terao Y, Ugawa
Y. Effects of thirty minutes mobile phone use on the human sensory cortex.
Clin Neurophysiol 2006 [Epub ahead of print].