自我運動感（vection）是指個體在缺乏實際身體位移的情況下，仍主觀感受到自身正在移動的知覺經驗。Shepard–Risset glissando 是一種藉由音高彷彿持續上升或下降，傳遞隱喻性方向資訊的聽覺錯覺。過去研究顯示，聽覺線索可以影響自我運動感，但多數研究主要探討聲源在空間中移動所提供的聽覺運動線索，或具有明確起始與終點的短暫音高變化。相較之下，持續性且不涉及聲源空間位移的音高運動，是否也能提供與自我運動方向相關的資訊，仍有待釐清。本研究探討持續性 Shepard–Risset glissando 所傳遞的升降方向線索，是否會在純聽覺與視聽情境中影響自我運動感。實驗一（32 人）在純聽覺情境中操弄滑音速度（快速、正常、慢速）與音高運動方向（上升、下降）；實驗二（42 人）與實驗三（22 人）將上升、下降及白噪音三種聽覺條件，分別搭配向上與向下兩種視覺運動方向。實驗二使用一般螢幕呈現視覺刺激，實驗三則將相同的視聽覺因素組合延伸至頭戴式顯示器（head-mounted display, HMD）情境。由於視覺運動通常誘發反方向的自我運動感，當滑音升降方向與視覺刺激預期誘發的自我運動方向相符時，該配對被定義為「視聽方向一致」。三個實驗皆測量自我運動感的發生率、自我運動感方向、起始時間、持續時間與主觀強度。實驗一顯示，純聽覺情境下，96.4%的Shepard–Risset glissando試次出現自我運動感回報。正常速度條件下的發生率高於慢速條件，但快速條件與正常或慢速條件均無顯著差異。此外，滑音升降方向所誘發的自我運動感發生率並無顯著差異。上升與下降 glissando 分別較常伴隨向上與向下的自我運動感；在方向可明確分類的試次中，上升glissando亦伴隨較長的持續時間與較高的主觀強度。實驗二與實驗三進一步顯示，在視聽情境中，自我運動感的發生主要由視覺運動主導，滑音升降方向與視聽一致性均未穩定改變發生率。然而，聽覺線索仍會調節自我運動感的主觀強度。兩個視聽實驗的主觀強度皆出現聽覺條件與視覺運動方向的交互作用。實驗二中，向下視覺運動搭配上升滑音時的主觀強度高於搭配下降滑音，而向上視覺運動則呈現相反結果。實驗三中，向下視覺運動搭配上升滑音時的主觀強度高於搭配下降滑音時；在向上視覺運動條件下，兩種滑音的主觀強度則無可靠差異。相較之下，起始時間與持續時間未在三個實驗中呈現一致效果。整體而言，持續性 Shepard–Risset glissando 所傳遞的滑音升降方向，在純聽覺情境中與高比例且具有特定方向的自我運動感相關；在視聽情境中，則主要調節由視覺運動所建立之自我運動感的主觀強度與方向特徵，而未穩定改變其發生率。整體而言，持續性 Shepard–Risset glissando 在純聽覺情境中與高比例且具方向性的自我運動感回報相關；在視聽情境中，則較像是在視覺運動所建立的方向框架下，輔助性地調節方向相關回報與主觀強度，而非穩定改變自我運動感的發生率。

Vection refers to the subjective experience of self-motion in the absence of corresponding physical displacement. Shepard–Risset glissandi are auditory illusions in which pitch appears to rise or fall continuously, thereby conveying metaphoric directional information. Although auditory cues can contribute to vection, previous research has primarily examined spatialized sound-source motion or finite pitch sweeps. It remains unclear whether sustained nonspatial pitch motion can provide directional information for self-motion perception, particularly when visual motion already establishes a strong vection framework. The present study examined whether pitch-motion information conveyed by sustained Shepard–Risset glissandi influenced vection in auditory-only and audiovisual contexts. Experiment 1 (n = 32) manipulated glissando speed (Fast, Normal, and Slow) and pitch-motion direction (Ascending, Descending) in an auditory-only context. Experiments 2 (n = 42) and 3 (n = 22) both paired three auditory conditions—Ascending, Descending, and White Noise—with two visual motion directions (Upward and Downward). Experiment 2 presented the visual stimuli on a monitor, whereas Experiment 3 extended the same audiovisual factorial combination using a head-mounted display (HMD). Because visual motion typically induces vection in the opposite direction, a pairing was defined as audiovisually congruent when pitch-motion direction corresponded to the self-motion direction expected to be induced by the visual stimulus. Across experiments, vection occurrence, reported vection direction, onset time, vection duration, and subjective intensity were assessed. In Experiment 1, vection was reported in 96.4% of the auditory-only Shepard–Risset glissandi trials. Vection occurrence was higher in the Normal than in the Slow condition, whereas the Fast condition did not differ significantly from either condition. Vection occurrence also did not differ significantly between the Ascending and Descending conditions. Ascending and Descending glissandi were more often associated with upward and downward vection, respectively; among trials with clearly classifiable directions, the Ascending condition was also associated with longer vection duration and greater subjective intensity. In the audiovisual contexts of Experiments 2 and 3, vection occurrence was primarily supported by visual motion, and neither pitch-motion direction nor audiovisual congruency consistently altered occurrence. Instead, both audiovisual experiments showed an auditory condition × visual motion direction interaction in subjective intensity. In Experiment 2, subjective intensity was higher for Ascending than Descending glissandi during Downward visual motion, whereas during Upward visual motion, subjective intensity was higher for Descending than Ascending glissandi. In Experiment 3, subjective intensity was higher for Ascending than Descending glissandi during Downward visual motion, whereas subjective intensity did not differ reliably between Ascending and Descending glissandi during Upward visual motion. Effects on onset time and vection duration were not consistent across the three experiments. These findings suggest that sustained nonspatial pitch motion can provide directional information for auditory-only vection, but in audiovisual contexts it functions mainly as a supplementary cue that modulates direction-related reports and subjective intensity within a visually defined self-motion framework.

Bagust, J. (2005). Assessment of verticality perception by a rod-and-frame test: Preliminary observations on the use of a computer monitor and video eye glasses. Archives of Physical Medicine and Rehabilitation, 86(5), 1062–1064. https://doi.org/10.1016/j.apmr.2004.05.022
Brainard, D. H. (1997). The Psychophysics Toolbox. Spatial Vision, 10(4), 433–436. https://doi.org/10.1163/156856897X00357
Brandt, T., Dichgans, J., & Koenig, E. (1973). Differential effects of central versus peripheral vision on egocentric and exocentric motion perception. Experimental Brain Research, 16(5), 476–491. https://doi.org/10.1007/BF00234474
Delle Monache, S., La Scaleia, B., Finazzi Agrò, A., Lacquaniti, F., & Zago, M. (2025). Psychophysical evidence for an internal model of gravity in the visual and vestibular estimates of vertical motion duration. Scientific Reports, 15, 10394. https://doi.org/10.1038/s41598-025-94512-1
Dichgans, J., & Brandt, T. (1978). Visual-vestibular interaction: Effects on self-motion perception and postural control. In R. Held, H. W. Leibowitz, & H.-L. Teuber (Eds.), Handbook of sensory physiology: Vol. 8. Perception (pp. 755–804). Springer. https://doi.org/10.1007/978-3-642-46354-9_25
Docherty, S., & Bagust, J. (2010). From line to dots: An improved computerised rod and frame system for testing subjective visual vertical and horizontal. BMC Research Notes, 3, Article 9. https://doi.org/10.1186/1756-0500-3-9
Keshavarz, B., & Berti, S. (2014). Integration of sensory information precedes the sensation of vection: A combined behavioral and event-related brain potential (ERP) study. Behavioural Brain Research, 259, 131–136. https://doi.org/10.1016/j.bbr.2013.10.045
Keshavarz, B., Hettinger, L. J., Vena, D., & Campos, J. L. (2014). Combined effects of auditory and visual cues on the perception of vection. Experimental Brain Research, 232(3), 827–836. https://doi.org/10.1007/s00221-013-3793-9
Keshavarz, B., Speck, M., Haycock, B., & Berti, S. (2017). Effect of different display types on vection and its interaction with motion direction and field dependence. i-Perception, 8(3), Article 2041669517707768. https://doi.org/10.1177/2041669517707768
Kleiner, M., Brainard, D. H., & Pelli, D. G. (2007). What’s new in Psychtoolbox-3? Perception, 36(ECVP Abstract Supplement), 14.
Kirollos, R., & Herdman, C. M. (2023). Caloric vestibular stimulation induces vestibular circular vection even with a conflicting visual display presented in a virtual reality headset. i-Perception, 14(2), 1–19. https://doi.org/10.1177/20416695231168093
Kooijman, L., Berti, S., Asadi, H., Nahavandi, S., & Keshavarz, B. (2024). Measuring vection: A review and critical evaluation of different methods for quantifying illusory self-motion. Behavior Research Methods, 56(3), 2292–2310. https://doi.org/10.3758/s13428-023-02148-8
Lackner, J. R. (1977). Induction of illusory self-rotation and nystagmus by a rotating sound-field. Aviation, Space, and Environmental Medicine, 48(2), 129–131.
Lappe, M., Bremmer, F., & van den Berg, A. V. (1999). Perception of self-motion from visual flow. Trends in Cognitive Sciences, 3(9), 329–336. https://doi.org/10.1016/S1364-6613(99)01364-9
Larsson, P., Västfjäll, D., & Kleiner, M. (2004). Perception of self-motion and presence in auditory virtual environments. In M. Alcañiz Raya & B. Rey Solaz (Eds.), Proceedings of the seventh annual international workshop PRESENCE 2004 (pp. 252–258). Editorial UPV. https://matthewlombard.com/ISPR/Proceedings/2004/Larsson%2C%20Vastfjall%2C%20Kleiner.pdf
Maeda, F., Kanai, R., & Shimojo, S. (2004). Changing pitch induced visual motion illusion. Current Biology, 14(23), R990–R991. https://doi.org/10.1016/j.cub.2004.11.018
McCormick, K., Lacey, S., Stilla, R., Nygaard, L. C., & Sathian, K. (2018). Neural basis of the crossmodal correspondence between auditory pitch and visuospatial elevation. Neuropsychologia, 112, 19–30. https://doi.org/10.1016/j.neuropsychologia.2018.02.029
Mursic, R. A., & Palmisano, S. (2020). The Shepard–Risset glissando: Identifying the origins of metaphorical auditory vection and motion sickness. Multisensory Research, 33(1), 61–86. https://doi.org/10.1163/22134808-20191450
Mursic, R. A., Riecke, B. E., Apthorp, D., & Palmisano, S. (2017). The Shepard–Risset glissando: Music that moves you. Experimental Brain Research, 235(10), 3111–3127. https://doi.org/10.1007/s00221-017-5033-1
Palmisano, S., Allison, R. S., Schira, M. M., & Barry, R. J. (2015). Future challenges for vection research: Definitions, functional significance, measures, and neural bases. Frontiers in Psychology, 6, Article 193. https://doi.org/10.3389/fpsyg.2015.00193
Parkinson, C., Kohler, P. J., Sievers, B., & Wheatley, T. (2012). Associations between auditory pitch and visual elevation do not depend on language: Evidence from a remote population. Perception, 41(7), 854–861. https://doi.org/10.1068/p7225
Pelli, D. G. (1997). The VideoToolbox software for visual psychophysics: Transforming numbers into movies. Spatial Vision, 10(4), 437–442. https://doi.org/10.1163/156856897X00366
Repasky, D. (2013, November 14). 10 hours of infinite fractal and falling Shepard’s tone [Video]. YouTube. https://www.youtube.com/watch?v=u9VMfdG873E
Riecke, B. E., & Jordan, J. D. (2015). Comparing the effectiveness of different displays in enhancing illusions of self-movement (vection). Frontiers in Psychology, 6, Article 713. https://doi.org/10.3389/fpsyg.2015.00713
Riecke, B. E., Schulte-Pelkum, J., Caniard, F., & Bülthoff, H. H. (2005). Influence of auditory cues on the visually-induced self-motion illusion (circular vection) in virtual reality. In M. Slater (Ed.), PRESENCE 2005: The 8th international workshop on presence: Conference proceedings (pp. 49–57). University College London. https://hdl.handle.net/11858/00-001M-0000-0013-D43B-4
Riecke, B. E., Väljamäe, A., & Schulte-Pelkum, J. (2009). Moving sounds enhance the visually-induced self-motion illusion (circular vection) in virtual reality. ACM Transactions on Applied Perception, 6(2), Article 7. https://doi.org/10.1145/1498700.1498701
Sadaghiani, S., Maier, J. X., & Noppeney, U. (2009). Natural, metaphoric, and linguistic auditory direction signals have distinct influences on visual motion processing. The Journal of Neuroscience, 29(20), 6490–6499. https://doi.org/10.1523/JNEUROSCI.5437-08.2009
Seno, T., Hasuo, E., Ito, H., & Nakajima, Y. (2012). Perceptually plausible sounds facilitate visually induced self-motion perception (vection). Perception, 41(5), 577–593. https://doi.org/10.1068/p7184
Väljamäe, A. (2009). Auditorily-induced illusory self-motion: A review. Brain Research Reviews, 61(2), 240–255. https://doi.org/10.1016/j.brainresrev.2009.07.001
Väljamäe, A., Larsson, P., Västfjäll, D., & Kleiner, M. (2005). Travelling without moving: Auditory scene cues for translational self-motion. In Proceedings of ICAD 05—Eleventh Meeting of the International Conference on Auditory Display (pp. 9–16). http://hdl.handle.net/1853/50193
Väljamäe, A., & Sell, S. (2014). The influence of imagery vividness on cognitive and perceptual cues in circular auditorily-induced vection. Frontiers in Psychology, 5, 1362. https://doi.org/10.3389/fpsyg.2014.01362
Witkin, H. A., & Asch, S. E. (1948). Studies in space orientation: IV. Further experiments on perception of the upright with displaced visual fields. Journal of Experimental Psychology, 38(6), 762–782. https://doi.org/10.1037/h0053671
Wright, W. G., DiZio, P., & Lackner, J. R. (2006). Perceived self-motion in two visual contexts: Dissociable mechanisms underlie perception. Journal of Vestibular Research, 16(1–2), 23–28. https://doi.org/10.3233/VES-2006-161-202