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Hadi Z, Pondeca Y, Rust HM, Seemungal BM. Electrophysiological markers of vestibular-mediated self-motion perception - A pilot study. Brain Res 2024; 1840:149048. [PMID: 38844198 DOI: 10.1016/j.brainres.2024.149048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2024] [Revised: 05/22/2024] [Accepted: 05/30/2024] [Indexed: 06/12/2024]
Abstract
Peripheral vestibular activation results in multi-level responses, from brainstem-mediated reflexes (e.g. vestibular ocular reflex - VOR) to perception of self-motion. While VOR responses indicate preserved vestibular peripheral and brainstem functioning, there are no automated measures of vestibular perception of self-motion - important since some patients with brain disconnection syndromes manifest a vestibular agnosia (intact VOR but impaired self-motion perception). Electroencephalography ('EEG') - may provide a surrogate marker of vestibular perception of self-motion. A related objective is obtaining an EEG marker of vestibular sensory signal processing, distinct from vestibular-motion perception. We performed a pilot study comparing EEG responses in the dark when healthy participants sat in a vibrationless computer-controlled motorised rotating chair moving at near threshold of self-motion perception, versus a second situation in which subjects sat in the chair at rest in the dark who could be induced (or not) into falsely perceiving self-motion. In both conditions subjects could perceive self-motion perception, but in the second there was no bottom-up reflex-brainstem activation. Time-frequency analyses showed: (i) alpha frequency band activity is linked to vestibular sensory-signal activation; and (ii) theta band activity is a marker of vestibular-mediated self-motion perception. Consistent with emerging animal data, our findings support the role of theta activity in the processing of self-motion perception.
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Affiliation(s)
- Zaeem Hadi
- Centre for Vestibular Neurology, Department of Brain Sciences, Imperial College London, UK.
| | - Yuscah Pondeca
- Centre for Vestibular Neurology, Department of Brain Sciences, Imperial College London, UK
| | - Heiko M Rust
- Centre for Vestibular Neurology, Department of Brain Sciences, Imperial College London, UK; Department of Neurology, University Hospital Basel, Switzerland
| | - Barry M Seemungal
- Centre for Vestibular Neurology, Department of Brain Sciences, Imperial College London, UK.
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2
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Kooijman L, Berti S, Asadi H, Nahavandi S, Keshavarz B. Measuring vection: a review and critical evaluation of different methods for quantifying illusory self-motion. Behav Res Methods 2024; 56:2292-2310. [PMID: 37369940 PMCID: PMC10991029 DOI: 10.3758/s13428-023-02148-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/17/2023] [Indexed: 06/29/2023]
Abstract
The sensation of self-motion in the absence of physical motion, known as vection, has been scientifically investigated for over a century. As objective measures of, or physiological correlates to, vection have yet to emerge, researchers have typically employed a variety of subjective methods to quantify the phenomenon of vection. These measures can be broadly categorized into the occurrence of vection (e.g., binary choice yes/no), temporal characteristics of vection (e.g., onset time/latency, duration), the quality of the vection experience (e.g., intensity rating scales, magnitude estimation), or indirect (e.g., distance travelled) measures. The present review provides an overview and critical evaluation of the most utilized vection measures to date and assesses their respective merit. Furthermore, recommendations for the selection of the most appropriate vection measures will be provided to assist with the process of vection research and to help improve the comparability of research findings across different vection studies.
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Affiliation(s)
- Lars Kooijman
- Institute for Intelligent Systems Research and Innovation, Deakin University, Geelong, Victoria, Australia.
| | - Stefan Berti
- Institute of Psychology, Johannes Gutenberg-University Mainz, Mainz, Germany
| | - Houshyar Asadi
- Institute for Intelligent Systems Research and Innovation, Deakin University, Geelong, Victoria, Australia
| | - Saeid Nahavandi
- Institute for Intelligent Systems Research and Innovation, Deakin University, Geelong, Victoria, Australia
- Harvard Paulson School of Engineering and Applied Sciences, Harvard University, Allston, MA, 02134, USA
| | - Behrang Keshavarz
- Department of Psychology, Toronto Metropolitan University, Toronto, Ontario, Canada
- KITE-Toronto Rehabilitation Institute, University Health Network (UHN), Toronto, Ontario, Canada
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3
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Harquel S, Cian C, Torlay L, Cousin E, Barraud PA, Bougerol T, Guerraz M. Modulation of Visually Induced Self-motion Illusions by α Transcranial Electric Stimulation over the Superior Parietal Cortex. J Cogn Neurosci 2024; 36:143-154. [PMID: 37870524 DOI: 10.1162/jocn_a_02074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2023]
Abstract
The growing popularity of virtual reality systems has led to a renewed interest in understanding the neurophysiological correlates of the illusion of self-motion (vection), a phenomenon that can be both intentionally induced or avoided in such systems, depending on the application. Recent research has highlighted the modulation of α power oscillations over the superior parietal cortex during vection, suggesting the occurrence of inhibitory mechanisms in the sensorimotor and vestibular functional networks to resolve the inherent visuo-vestibular conflict. The present study aims to further explore this relationship and investigate whether neuromodulating these waves could causally affect the quality of vection. In a crossover design, 22 healthy volunteers received high amplitude and focused α-tACS (transcranial alternating current stimulation) over the superior parietal cortex while experiencing visually induced vection triggered by optokinetic stimulation. The tACS was tuned to each participant's individual α peak frequency, with θ-tACS and sham stimulation serving as controls. Overall, participants experienced better quality vection during α-tACS compared with control θ-tACS and sham stimulations, as quantified by the intensity of vection. The observed neuromodulation supports a causal relationship between parietal α oscillations and visually induced self-motion illusions, with their entrainment triggering overinhibition of the conflict within the sensorimotor and vestibular functional networks. These results confirm the potential of noninvasive brain stimulation for modulating visuo-vestibular conflicts, which could help to enhance the sense of presence in virtual reality environments.
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Affiliation(s)
- Sylvain Harquel
- Université Grenoble-Alpes, Université Savoie Mont Blanc, CNRS, UMR5105, LPNC, Grenoble, France
- Defitech Chair of Clinical Neuroengineering, Center for Neuroprosthetics (CNP) and Brain Mind Institute (BMI), Swiss Federal Institute of Technology Lausanne (EPFL), Campus Biotech, Geneva, Switzerland
| | - Corinne Cian
- Université Grenoble-Alpes, Université Savoie Mont Blanc, CNRS, UMR5105, LPNC, Grenoble, France
- Institut de Recherche Biomédicale des Armées, Brétigny sur Orge, France
| | - Laurent Torlay
- Université Grenoble-Alpes, Université Savoie Mont Blanc, CNRS, UMR5105, LPNC, Grenoble, France
| | - Emilie Cousin
- Université Grenoble-Alpes, Université Savoie Mont Blanc, CNRS, UMR5105, LPNC, Grenoble, France
| | - Pierre-Alain Barraud
- Université Grenoble-Alpes, CNRS, CHU Grenoble-Alpes, Grenoble INP, TIMC-IMAG, Grenoble, France
| | - Thierry Bougerol
- Centre Hospitalier Université Grenoble-Alpes, Pôle Psychiatrie, Grenoble, France
- Université Grenoble-Alpes, Inserm, U1216, Grenoble Institut des Neurosciences, Grenoble, France
| | - Michel Guerraz
- Université Grenoble-Alpes, Université Savoie Mont Blanc, CNRS, UMR5105, LPNC, Grenoble, France
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4
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Andrievskaia P, Berti S, Spaniol J, Keshavarz B. Exploring neurophysiological correlates of visually induced motion sickness using electroencephalography (EEG). Exp Brain Res 2023; 241:2463-2473. [PMID: 37650899 DOI: 10.1007/s00221-023-06690-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Accepted: 08/12/2023] [Indexed: 09/01/2023]
Abstract
Visually induced motion sickness (VIMS) is a common phenomenon when using visual devices such as smartphones and virtual reality applications, with symptoms including nausea, fatigue, and headache. To date, the neuro-cognitive processes underlying VIMS are not fully understood. Previous studies using electroencephalography (EEG) delivered mixed findings, with some reporting an increase in delta and theta power, and others reporting increases in alpha and beta frequencies. The goal of the study was to gain further insight into EEG correlates for VIMS. Participants viewed a VIMS-inducing visual stimulus, composed of moving black-and-white vertical bars presented on an array of three adjacent monitors. The EEG was recorded during visual stimulation and VIMS ratings were recorded after each trial using the Fast Motion Sickness Scale. Time-frequency analyses were conducted comparing neural activity of participants reporting minimal VIMS (n = 21) and mild-moderate VIMS (n = 12). Results suggested a potential increase in delta power in the centro-parietal regions (CP2) and a decrease in alpha power in the central regions (Cz) for participants experiencing mild-moderate VIMS compared to those with minimal VIMS. Event-related spectral perturbations (ERSPs) suggested that group differences in EEG activity developed with increasing duration of a trial. These results support the hypothesis that the EEG might be sensitive to differences in information processing in VIMS and minimal VIMS contexts, and indicate that it may be possible to identify neurophysiological correlate of VIMS. Differences in EEG activity related to VIMS may reflect differential processing of conflicting visual and vestibular sensory information.
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Affiliation(s)
- Polina Andrievskaia
- KITE Research Institute, Toronto Rehabilitation Institute-University Health Network, 550 University Avenue, Toronto, ON, M5G 2A2, Canada
- Department of Psychology, Toronto Metropolitan University, Toronto, Canada
| | - Stefan Berti
- Department of Clinical Psychology and Neuropsychology, Johannes Gutenberg University, Mainz, Germany
| | - Julia Spaniol
- Department of Psychology, Toronto Metropolitan University, Toronto, Canada
| | - Behrang Keshavarz
- KITE Research Institute, Toronto Rehabilitation Institute-University Health Network, 550 University Avenue, Toronto, ON, M5G 2A2, Canada.
- Department of Psychology, Toronto Metropolitan University, Toronto, Canada.
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Dizmen CJ, So RH. Vection induced by a pair of patches of synchronized visual motion stimuli covering total field of views as small as 10 square-degrees. Iperception 2023; 14:20416695231201463. [PMID: 37766824 PMCID: PMC10521291 DOI: 10.1177/20416695231201463] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Accepted: 08/30/2023] [Indexed: 09/29/2023] Open
Abstract
Vection (illusion of self-motion) is known to be induced by watching large field-of-view (FOV) moving scenes. In our study, we investigated vection induced by small FOV stimuli. Three experiments were conducted in 45 sessions to analyze vection provoked by moving scenes covering total FOVs as small as 10 square-degrees. Results indicated that 88% of the participants reported vection while watching two small patches of moving dots (1° horizontal by 5° vertical, each) placed on the left and right sides of the observers. This is less than a quarter of the total visual area of two Apple Watches viewed at a distance of 40 cm. Occlusion of the visual field between the two display patches significantly increased the levels of rated vection. Similarly, increasing the speed of the moving dots of the two display patches from about 5 to 25 °/sec increased the levels of rated vection significantly. The location of the two patches in the horizontal visual field did not affect the vection perception significantly. When the two straight stripes of dots were moving in opposite directions, participants perceived circular vection. The observers connected the two stimuli in their minds and perceived them as parts of a single occluded background. The findings of this study are relevant to the design of mobile devices (e.g., smartphones) and wearable technology (e.g., smart watches) with small display areas.
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Souchet AD, Lourdeaux D, Burkhardt JM, Hancock PA. Design guidelines for limiting and eliminating virtual reality-induced symptoms and effects at work: a comprehensive, factor-oriented review. Front Psychol 2023; 14:1161932. [PMID: 37359863 PMCID: PMC10288216 DOI: 10.3389/fpsyg.2023.1161932] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Accepted: 05/16/2023] [Indexed: 06/28/2023] Open
Abstract
Virtual reality (VR) can induce side effects known as virtual reality-induced symptoms and effects (VRISE). To address this concern, we identify a literature-based listing of these factors thought to influence VRISE with a focus on office work use. Using those, we recommend guidelines for VRISE amelioration intended for virtual environment creators and users. We identify five VRISE risks, focusing on short-term symptoms with their short-term effects. Three overall factor categories are considered: individual, hardware, and software. Over 90 factors may influence VRISE frequency and severity. We identify guidelines for each factor to help reduce VR side effects. To better reflect our confidence in those guidelines, we graded each with a level of evidence rating. Common factors occasionally influence different forms of VRISE. This can lead to confusion in the literature. General guidelines for using VR at work involve worker adaptation, such as limiting immersion times to between 20 and 30 min. These regimens involve taking regular breaks. Extra care is required for workers with special needs, neurodiversity, and gerontechnological concerns. In addition to following our guidelines, stakeholders should be aware that current head-mounted displays and virtual environments can continue to induce VRISE. While no single existing method fully alleviates VRISE, workers' health and safety must be monitored and safeguarded when VR is used at work.
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Affiliation(s)
- Alexis D. Souchet
- Heudiasyc UMR 7253, Alliance Sorbonne Université, Université de Technologie de Compiègne, CNRS, Compiègne, France
- Institute for Creative Technologies, University of Southern California, Los Angeles, CA, United States
| | - Domitile Lourdeaux
- Heudiasyc UMR 7253, Alliance Sorbonne Université, Université de Technologie de Compiègne, CNRS, Compiègne, France
| | | | - Peter A. Hancock
- Department of Psychology, University of Central Florida, Orlando, FL, United States
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7
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Kooijman L, Asadi H, Mohamed S, Nahavandi S. A virtual reality study investigating the train illusion. ROYAL SOCIETY OPEN SCIENCE 2023; 10:221622. [PMID: 37063997 PMCID: PMC10090874 DOI: 10.1098/rsos.221622] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Accepted: 03/20/2023] [Indexed: 06/19/2023]
Abstract
The feeling of self-movement that occurs in the absence of physical motion is often referred to as vection, which is commonly exemplified using the train illusion analogy (TIA). Limited research exists on whether the TIA accurately exemplifies the experience of vection in virtual environments (VEs). Few studies complemented their vection research with participants' qualitative feedback or by recording physiological responses, and most studies used stimuli that contextually differed from the TIA. We investigated whether vection is experienced differently in a VE replicating the TIA compared to a VE depicting optic flow by recording subjective and physiological responses. Additionally, we explored participants' experience through an open question survey. We expected the TIA environment to induce enhanced vection compared to the optic flow environment. Twenty-nine participants were visually and audibly immersed in VEs that either depicted optic flow or replicated the TIA. Results showed optic flow elicited more compelling vection than the TIA environment and no consistent physiological correlates to vection were identified. The post-experiment survey revealed discrepancies between participants' quantitative and qualitative feedback. Although the dynamic content may outweigh the ecological relevance of the stimuli, it was concluded that more qualitative research is needed to understand participants' vection experience in VEs.
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Affiliation(s)
- Lars Kooijman
- Institute for Intelligent Systems Research and Innovation, Deakin University, Geelong, Victoria, Australia
| | - Houshyar Asadi
- Institute for Intelligent Systems Research and Innovation, Deakin University, Geelong, Victoria, Australia
| | - Shady Mohamed
- Institute for Intelligent Systems Research and Innovation, Deakin University, Geelong, Victoria, Australia
| | - Saeid Nahavandi
- Institute for Intelligent Systems Research and Innovation, Deakin University, Geelong, Victoria, Australia
- Harvard Paulson School of Engineering and Applied Sciences, Harvard University, Allston, MA 02134, USA
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8
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Reuten AJC, Smeets JBJ, Martens MH, Bos JE. Self-motion perception without sensory motion. Exp Brain Res 2022; 240:2677-2685. [PMID: 35986767 PMCID: PMC9510117 DOI: 10.1007/s00221-022-06442-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Accepted: 08/07/2022] [Indexed: 11/04/2022]
Abstract
AbstractVarious studies have demonstrated a role for cognition on self-motion perception. Those studies all concerned modulations of the perception of a physical or visual motion stimulus. In our study, however, we investigated whether cognitive cues could elicit a percept of oscillatory self-motion in the absence of sensory motion. If so, we could use this percept to investigate if the resulting mismatch between estimated self-motion and a lack of corresponding sensory signals is motion sickening. To that end, we seated blindfolded participants on a swing that remained motionless during two conditions, apart from a deliberate perturbation at the start of each condition. The conditions only differed regarding instructions, a secondary task and a demonstration, which suggested either a quick halt (“Distraction”) or continuing oscillations of the swing (“Focus”). Participants reported that the swing oscillated with larger peak-to-peak displacements and for a longer period of time in the Focus condition. That increase was not reflected in the reported motion sickness scores, which did not differ between the two conditions. As the reported motion was rather small, the lack of an effect on the motion sickness response can be explained by assuming a subthreshold neural conflict. Our results support the existence of internal models relevant to sensorimotor processing and the potential of cognitive (behavioral) therapies to alleviate undesirable perceptual issues to some extent. We conclude that oscillatory self-motion can be perceived in the absence of related sensory stimulation, which advocates for the acknowledgement of cognitive cues in studies on self-motion perception.
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9
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Murovec B, Spaniol J, Campos JL, Keshavarz B. Enhanced vection in older adults: Evidence for age-related effects in multisensory vection experiences. Perception 2022; 51:3010066221113770. [PMID: 35942780 PMCID: PMC9478596 DOI: 10.1177/03010066221113770] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Accepted: 06/28/2022] [Indexed: 11/15/2022]
Abstract
The illusion of self-motion (vection) is a multisensory phenomenon elicited by visual, auditory, tactile, or other sensory cues. Aging is often associated with changes in sensory acuity, visual motion perception, and multisensory integration, processes which may influence vection perception. However, age-related differences in vection have received little study to date. Thus, the objective of the present study was to investigate age-related differences in vection during multisensory stimulation. Nineteen younger adults and 19 older adults were exposed to rotating visual, auditory, and tactile stimuli (separately or in combination) at a speed of 45°/s inside a VR laboratory inducing circular vection. The size of the field-of-view (FOV) was large (240°), medium (75°), small (30°), or contained no visuals. Vection intensity and duration were reported verbally after each trial. Overall, older adults experienced significantly stronger and longer vection compared to younger adults. Additionally, there were main effects of FOV and sensory cues, such that larger FOVs and the presence of auditory and tactile stimulation increased vection ratings for both age groups. These findings support the idea that vection is a multisensory experience that can be elicited by visual, auditory, and tactile stimuli and demonstrates these effects for the first time in older adults.
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Affiliation(s)
- Brandy Murovec
- The KITE Research Institute, Toronto Rehabilitation
Institute-University Health Network, Canada; Toronto Metropolitan University,
Canada
| | | | - Jennifer L. Campos
- The KITE Research Institute, Toronto Rehabilitation
Institute-University Health Network, Canada; University of Toronto, Canada
| | - Behrang Keshavarz
- The KITE Research Institute, Toronto Rehabilitation
Institute-University Health Network Canada; Toronto Metropolitan University,
Canada
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10
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Murovec B, Spaniol J, Campos JL, Keshavarz B. Multisensory Effects on Illusory Self-Motion (Vection): the Role of Visual, Auditory, and Tactile Cues. Multisens Res 2021; 34:1-22. [PMID: 34384047 DOI: 10.1163/22134808-bja10058] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Accepted: 07/14/2021] [Indexed: 11/19/2022]
Abstract
A critical component to many immersive experiences in virtual reality (VR) is vection, defined as the illusion of self-motion. Traditionally, vection has been described as a visual phenomenon, but more recent research suggests that vection can be influenced by a variety of senses. The goal of the present study was to investigate the role of multisensory cues on vection by manipulating the availability of visual, auditory, and tactile stimuli in a VR setting. To achieve this, 24 adults (Mage = 25.04) were presented with a rotating stimulus aimed to induce circular vection. All participants completed trials that included a single sensory cue, a combination of two cues, or all three cues presented together. The size of the field of view (FOV) was manipulated across four levels (no-visuals, small, medium, full). Participants rated vection intensity and duration verbally after each trial. Results showed that all three sensory cues induced vection when presented in isolation, with visual cues eliciting the highest intensity and longest duration. The presence of auditory and tactile cues further increased vection intensity and duration compared to conditions where these cues were not presented. These findings support the idea that vection can be induced via multiple types of sensory inputs and can be intensified when multiple sensory inputs are combined.
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Affiliation(s)
- Brandy Murovec
- KITE, Toronto Rehabilitation Institute-University Health Network, Toronto, ON M5G 2A2, Canada
- Department of Psychology, Ryerson University, Toronto, ON M5B 2K3, Canada
| | - Julia Spaniol
- Department of Psychology, Ryerson University, Toronto, ON M5B 2K3, Canada
| | - Jennifer L Campos
- KITE, Toronto Rehabilitation Institute-University Health Network, Toronto, ON M5G 2A2, Canada
- Department of Psychology, University of Toronto, Toronto, ON M5S 3G3, Canada
| | - Behrang Keshavarz
- KITE, Toronto Rehabilitation Institute-University Health Network, Toronto, ON M5G 2A2, Canada
- Department of Psychology, Ryerson University, Toronto, ON M5B 2K3, Canada
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11
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Obereisenbuchner F, Dowsett J, Taylor PCJ. Self-initiation Inhibits the Postural and Electrophysiological Responses to Optic Flow and Button Pressing. Neuroscience 2021; 470:37-51. [PMID: 34273415 DOI: 10.1016/j.neuroscience.2021.07.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Revised: 07/02/2021] [Accepted: 07/06/2021] [Indexed: 10/20/2022]
Abstract
As we move through our environment, our visual system is presented with optic flow, a potentially important cue for perception, navigation and postural control. How does the brain anticipate the optic flow that arises as a consequence of our own movement? Converging evidence suggests that stimuli are processed differently by the brain if occurring as a consequence of self-initiated actions, compared to when externally generated. However, this has mainly been demonstrated with auditory stimuli. It is not clear how this occurs with optic flow. We measured behavioural, neurophysiological and head motion responses of 29 healthy participants to radially expanding, vection-inducing optic flow stimuli, simulating forward transitional motion, which were either initiated by the participant's own button-press ("self-initiated flow") or by the computer ("passive flow"). Self-initiation led to a prominent and left-lateralized inhibition of the flow-evoked posterior event-related alpha desynchronization (ERD), and a stabilisation of postural responses. Neither effect was present in control button-press-only trials, without optic flow. Additionally, self-initiation also produced a large event-related potential (ERP) negativity between 130-170 ms after optic flow onset. Furthermore, participants' visual induced motion sickness (VIMS) and vection intensity ratings correlated positively across the group - although many participants felt vection in the absence of any VIMS, none reported the opposite combination. Finally, we found that the simple act of making a button press leads to a detectable head movement even when using a chin rest. Taken together, our results indicate that the visual system is capable of predicting optic flow when self-initiated, to affect behaviour.
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Affiliation(s)
- Florian Obereisenbuchner
- MMRS - Munich Medical Research School, University Hospital, LMU Munich, Germany; Faculty of Medicine, LMU Munich, Germany.
| | - James Dowsett
- Department of Neurology, University Hospital, LMU Munich, Germany; German Center for Vertigo and Balance Disorders, University Hospital, LMU Munich, Germany; Department of Psychology, LMU Munich, Germany.
| | - Paul C J Taylor
- Department of Neurology, University Hospital, LMU Munich, Germany; German Center for Vertigo and Balance Disorders, University Hospital, LMU Munich, Germany; Department of Psychology, LMU Munich, Germany; Faculty of Philosophy and Philosophy of Science, LMU Munich, Germany; Munich Center for Neurosciences - Brain and Mind, LMU Munich, Germany.
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