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Experimental Brain Research Oct 2022Various studies have demonstrated a role for cognition on self-motion perception. Those studies all concerned modulations of the perception of a physical or visual...
Various 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.
Topics: Cues; Humans; Motion; Motion Perception; Motion Sickness; Self Concept; Visual Perception
PubMed: 35986767
DOI: 10.1007/s00221-022-06442-3 -
Journal of Neurophysiology Nov 2022Self-motion through an environment induces various sensory signals, i.e., visual, vestibular, auditory, or tactile. Numerous studies have investigated the role of visual...
Self-motion through an environment induces various sensory signals, i.e., visual, vestibular, auditory, or tactile. Numerous studies have investigated the role of visual and vestibular stimulation for the perception of self-motion direction (heading). Here, we investigated the rarely considered interaction of visual and tactile stimuli in heading perception. Participants were presented optic flow simulating forward self-motion across a horizontal ground plane (visual), airflow toward the participants' forehead (tactile), or both. In separate blocks of trials, participants indicated perceived heading from unimodal visual or tactile or bimodal sensory signals. In bimodal trials, presented headings were either spatially congruent or incongruent with a maximum offset between visual and tactile heading of 30°. To investigate the reference frame in which visuo-tactile heading is encoded, we varied head and eye orientation during presentation of the stimuli. Visual and tactile stimuli were designed to achieve comparable precision of heading reports between modalities. Nevertheless, in bimodal trials heading perception was dominated by the visual stimulus. A change of head orientation had no significant effect on perceived heading, whereas, surprisingly, a change in eye orientation affected tactile heading perception. Overall, we conclude that tactile flow is more important to heading perception than previously thought. We investigated heading perception from visual-only (optic flow), tactile-only (tactile flow), or bimodal self-motion stimuli in different conditions varying in head and eye position. Overall, heading perception was body or world centered and non-Bayes optimal and revealed a centripetal bias. Although being visually dominated, tactile flow revealed a significant influence during bimodal heading perception.
Topics: Humans; Motion Perception; Optic Flow; Vestibule, Labyrinth; Touch Perception; Touch; Photic Stimulation; Visual Perception
PubMed: 36259667
DOI: 10.1152/jn.00231.2022 -
Annual Review of Neuroscience Jul 2023How neurons detect the direction of motion is a prime example of neural computation: Motion vision is found in the visual systems of virtually all sighted animals, it is... (Review)
Review
How neurons detect the direction of motion is a prime example of neural computation: Motion vision is found in the visual systems of virtually all sighted animals, it is important for survival, and it requires interesting computations with well-defined linear and nonlinear processing steps-yet the whole process is of moderate complexity. The genetic methods available in the fruit fly and the charting of a connectome of its visual system have led to rapid progress and unprecedented detail in our understanding of how neurons compute the direction of motion in this organism. The picture that emerged incorporates not only the identity, morphology, and synaptic connectivity of each neuron involved but also its neurotransmitters, its receptors, and their subcellular localization. Together with the neurons' membrane potential responses to visual stimulation, this information provides the basis for a biophysically realistic model of the circuit that computes the direction of visual motion.
Topics: Animals; Motion Perception; Visual Pathways; Drosophila; Vision, Ocular; Neurons; Photic Stimulation
PubMed: 37428604
DOI: 10.1146/annurev-neuro-080422-111929 -
Philosophical Transactions of the Royal... Sep 2023To navigate and guide adaptive behaviour in a dynamic environment, animals must accurately estimate their own motion relative to the external world. This is a... (Review)
Review
To navigate and guide adaptive behaviour in a dynamic environment, animals must accurately estimate their own motion relative to the external world. This is a fundamentally multisensory process involving integration of visual, vestibular and kinesthetic inputs. Ideal observer models, paired with careful neurophysiological investigation, helped to reveal how visual and vestibular signals are combined to support perception of linear self-motion direction, or heading. Recent work has extended these findings by emphasizing the dimension of time, both with regard to stimulus dynamics and the trade-off between speed and accuracy. Both time and certainty-i.e. the degree of confidence in a multisensory decision-are essential to the ecological goals of the system: terminating a decision process is necessary for timely action, and predicting one's accuracy is critical for making multiple decisions in a sequence, as in navigation. Here, we summarize a leading model for multisensory decision-making, then show how the model can be extended to study confidence in heading discrimination. Lastly, we preview ongoing efforts to bridge self-motion perception and navigation , including closed-loop virtual reality and active self-motion. The design of unconstrained, ethologically inspired tasks, accompanied by large-scale neural recordings, raise promise for a deeper understanding of spatial perception and decision-making in the behaving animal. This article is part of the theme issue 'Decision and control processes in multisensory perception'.
Topics: Animals; Motion Perception; Space Perception; Vestibule, Labyrinth; Movement; Adaptation, Psychological; Visual Perception; Photic Stimulation
PubMed: 37545301
DOI: 10.1098/rstb.2022.0333 -
Journal of Neurology Oct 2022Current diagnostic criteria for bilateral vestibulopathy (BV) primarily involve measurements of vestibular reflexes. Perceptual self-motion thresholds however, are not...
OBJECTIVE
Current diagnostic criteria for bilateral vestibulopathy (BV) primarily involve measurements of vestibular reflexes. Perceptual self-motion thresholds however, are not routinely measured and their clinical value in this specific population is not yet fully determined. Objectives of this study were (1) to compare perceptual self-motion thresholds between BV patients and control subjects, and (2) to explore patterns of self-motion perception performance and vestibular function in BV patients.
METHODS
Thirty-seven BV patients and 34 control subjects were included in this study. Perceptual self-motion thresholds were measured in both groups using a CAREN platform (Motek Medical BV, Amsterdam, The Netherlands). Vestibular function was evaluated (only in BV patients) by the caloric test, torsion swing test, video head impulse test of all semicircular canals, and cervical- and ocular vestibular-evoked myogenic potentials. Differences in thresholds between both groups were analyzed. Hierarchical cluster analysis was performed to visualize patterns between self-motion perception and vestibular function within the group of BV patients.
RESULTS
Perceptual self-motion thresholds were significantly higher in BV patients compared to control subjects, regarding nearly all rotations and translations (depending on the age group) (p ≤ 0.001). Cluster analysis showed that within the group of BV patients, higher perceptual self-motion thresholds were generally associated with lower vestibular test results (significant for yaw rotation, caloric test, torsion swing test, and video head impulse test (p ≤ 0.001)).
CONCLUSION
Self-motion perception is significantly decreased in BV patients compared to control subjects regarding nearly all rotations and translations. Furthermore, decreased self-motion perception is generally associated with lower residual vestibular function in BV patients.
TRIAL REGISTRATION
Trial registration number NL52768.068.15/METC.
Topics: Bilateral Vestibulopathy; Head Impulse Test; Humans; Motion Perception; Reflex, Vestibulo-Ocular; Vestibular Evoked Myogenic Potentials
PubMed: 34263351
DOI: 10.1007/s00415-021-10695-3 -
Trends in Cognitive Sciences Nov 2021Perceptual gaps can be caused by objects in the foreground temporarily occluding objects in the background or by eyeblinks, which briefly but frequently interrupt visual... (Review)
Review
Perceptual gaps can be caused by objects in the foreground temporarily occluding objects in the background or by eyeblinks, which briefly but frequently interrupt visual information. Resolving visual motion across perceptual gaps is particularly challenging, as object position changes during the gap. We examine how visual motion is maintained and updated through externally driven (occlusion) and internally driven (eyeblinks) perceptual gaps. Focusing on both phenomenology and potential mechanisms such as suppression, extrapolation, and integration, we present a framework for how perceptual gaps are resolved over space and time. We finish by highlighting critical questions and directions for future work.
Topics: Humans; Motion Perception
PubMed: 34489180
DOI: 10.1016/j.tics.2021.07.017 -
Philosophical Transactions of the Royal... Jan 2023Stereoscopic depth perception is possible with luminance-defined target velocities at least as high as 600° s, up to the limit of 30 Hz imposed by the high-temporal... (Review)
Review
Stereoscopic depth perception is possible with luminance-defined target velocities at least as high as 600° s, up to the limit of 30 Hz imposed by the high-temporal frequency cut-off of the eye. The limitation for perceiving depth from stereo disparity of moving targets is not their velocity but the temporal frequency bandwidth of the eye, which is affected by adaption state. Stereoacuity for a depth shift in a horizontally moving grating depends not on spatial disparity between corresponding luminance points in spatial units of arc min, but on the spatial shift as a fixed proportion of the period of the grating, in other words, on the phase angle difference between the two eyes, as is also the case for obliquely orientated, stationary gratings. Phase differences explain not only the classic Pulfrich stereophenomenon but its equivalent with dynamic visual noise, and a new effect in which depth results from interocular phase differences in luminance modulation. This article is part of a discussion meeting issue 'New approaches to 3D vision'.
Topics: Vision Disparity; Depth Perception; Visual Acuity; Vision, Ocular; Vision, Binocular; Motion Perception
PubMed: 36511411
DOI: 10.1098/rstb.2021.0462 -
Vision Research Jul 2022The present study investigated hemispheric symmetry of cortical functions, in terms of the chromatic motion mechanism. A series of experiments examined the visual...
The present study investigated hemispheric symmetry of cortical functions, in terms of the chromatic motion mechanism. A series of experiments examined the visual sensitivities to chromatic and achromatic stimuli with or without motion, presented in either of the two (left or right) visual hemifields. Experiment 1 measured, individually, the subjective isoluminance of red/green stimuli for each visual field. Experiment 2 examined the visual field differences of the detection thresholds for static stimuli with the isoluminant color contrast and achromatic luminance contrast. Subsequent experiments measured contrast thresholds for motion detection (Experiment 3) and motion direction discrimination (Experiment 4) with both chromatic and achromatic stimuli. No visual field differences between thresholds were found in Experiments 1 and 2, whereas in Experiments 3 and 4, thresholds for the chromatic conditions were found to be lower in the left than in the right visual field, suggesting functional lateralization of the early motion mechanism with chromatic information in motion detection and direction discrimination.
Topics: Color Perception; Contrast Sensitivity; Humans; Motion Perception; Visual Fields
PubMed: 35248888
DOI: 10.1016/j.visres.2022.108027 -
Vision Research Nov 2021Saccadic eye movements can drastically affect motion perception: during saccades, the stationary surround is swept rapidly across the retina and contrast sensitivity is...
Saccadic eye movements can drastically affect motion perception: during saccades, the stationary surround is swept rapidly across the retina and contrast sensitivity is suppressed. However, after saccades, contrast sensitivity is enhanced for color and high-spatial frequency stimuli and reflexive tracking movements known as ocular following responses (OFR) are enhanced in response to large field motion. Additionally, OFR and postsaccadic enhancement of neural activity in primate motion processing areas are well correlated. It is not yet known how this postsaccadic enhancement arises. Therefore, we tested if the enhancement can be explained by changes in the balance of centre-surround antagonism in motion processing, where spatial summation is favoured at low contrasts and surround suppression is favoured at high contrasts. We found motion perception was selectively enhanced immediately after saccades for high spatial frequency stimuli, consistent with previously reported selective postsaccadic enhancement of contrast sensitivity for flashed high spatial frequency stimuli. The observed enhancement was also associated with changes in spatial summation and suppression, as well as contrast facilitation and inhibition, suggesting that motion processing is augmented to maximise visual perception immediately after saccades. The results highlight that spatial and contrast properties of underlying neural mechanisms for motion processing can be affected by an antecedent saccade for highly detailed stimuli and are in line with studies that show behavioural and neuronal enhancement of motion processing in non-human primates.
Topics: Animals; Motion Perception; Neurons; Photic Stimulation; Saccades; Vision, Ocular; Visual Perception
PubMed: 34280816
DOI: 10.1016/j.visres.2021.06.011 -
Journal of Neurophysiology Oct 2021Besides providing information on elementary properties of objects, like texture, roughness, and softness, the sense of touch is also important in building a... (Review)
Review
Besides providing information on elementary properties of objects, like texture, roughness, and softness, the sense of touch is also important in building a representation of object movement and the movement of our hands. Neural and behavioral studies shed light on the mechanisms and limits of our sense of touch in the perception of texture and motion, and of its role in the control of movement of our hands. The interplay between the geometrical and mechanical properties of the touched objects, such as shape and texture, the movement of the hand exploring the object, and the motion felt by touch, will be discussed in this article. Interestingly, the interaction between motion and textures can generate perceptual illusions in touch. For example, the orientation and the spacing of the texture elements on a static surface induces the illusion of surface motion when we move our hand on it or can elicit the perception of a curved trajectory during sliding, straight hand movements. In this work we present a multiperspective view that encompasses both the perceptual and the motor aspects, as well as the response of peripheral and central nerve structures, to analyze and better understand the complex mechanisms underpinning the tactile representation of texture and motion. Such a better understanding of the spatiotemporal features of the tactile stimulus can reveal novel transdisciplinary applications in neuroscience and haptics.
Topics: Humans; Illusions; Motion Perception; Somatosensory Cortex; Touch; Touch Perception
PubMed: 34495782
DOI: 10.1152/jn.00583.2020