scholarly journals Evaluating the concepts of weak and subcognitive integration - an experimental study using vibrotactile sensory augmentation for the blind

2020 ◽  
Author(s):  
Anna Ricarda Luther
Keyword(s):  
Cognitive Processing ◽  
Subjective Experience ◽  
Angular Rotation ◽  
Sensory Augmentation ◽  
Directional Information ◽  
Attentional Resources ◽  
Completion Task ◽  
Attentional Load ◽  
Straight Line ◽  
Triangle Completion

Navigating in foreign surroundings necessitates peak concentration for blind travellers. Yet, most navigational aids heavily rely on attentional resources as well as on audition. Audition is a modality of supreme importance for the blind, allowing to react to cues of the immediate environment. Thus, it would be highly beneficial for a navigational aid for the blind to not or only partially rely on attentional resources and be easily interpreted and integrated into behaviour. Following the sensorimotor contingency (SMC) theory, which is embedded in the theoretical framework of embodiment, such endeavour has the potential to succeed by employing sensory augmentation devices. According to SMC theory, statistic regularities termed sensorimotor contingencies coupling action and perception are constitutive of conscious perception. Consequentially, since those regularities differ in between modality, also the qualitative experience of different modalities differ. Following this line of thought, new SMCs can be created through sensory augmentation devices and learned by exploring the SMC. The objective of this study is to further investigate if and to what extent such sensory augmentation device can be integrated into behaviour. Therefore, the weak integration hypothesis and the sub-cognitive processing hypothesis as established by Nagel et al. (2005) will be employed to evaluate the integration according to their criteria.Eleven congenitally and adventitiously blind adult subjects were provided with vibrotactile directional information of the magnetic north around the waist through a device termed naviBelt for seven weeks. At the beginning and at the middle of the study the integration of the signal of five participants was assessed using a battery of behavioural tests. These tests consisted of a straight-line-walking task, an angular rotation task and a triangle completion task. Furthermore, throughout the period of study all participants completed preliminary, weekly and final questionnaires, inspired by Kärcher et al. (2012). The questionnaires allowed to gain a more holistic picture of the subjective experience and the self-assessed benefits of the belt. In addition, two deaf-blind participants were provided with the belt for three to four weeks and answered questionnaires adjusted to their needs.The straight-line-walking task showed instant improvements in path stabilization when provided with the belt. In two participants characteristic behaviour of the sub-cognitive processing hypothesis is obtained. An overall improvement independent of whether the belt is worn or not is especially evident after the training period in the angular rotation task. This indicates an enhanced direction estimation accuracy, which is highly related to the understanding of the belt signal. Evidence for enhanced path integration and navigational skills through the belt can be found in the results of the triangle completion task. For two participants the performance improved even with an additional attentional load, hinting towards sub-cognitive processing.Overall, the data supports the weak integration hypothesis and points towards the sub-cognitive processing hypothesis and thus show that SMCs can be learned, which is in line with the theory of embodiment. Crucially, the study further exemplifies how such integration into behaviour can be of great benefit as assistive device for blind and deaf-blind.

scholarly journals Impact of a Vibrotactile Belt on Emotionally Challenging Everyday Situations of the Blind

Sensors ◽  
2021 ◽  
Vol 21 (21) ◽  
pp. 7384
Author(s):  
Charlotte Brandebusemeyer ◽  
Anna Ricarda Luther ◽  
Sabine U. König ◽  
Peter König ◽  
Silke M. Kärcher
Keyword(s):  
Emotional Impact ◽  
Vibrotactile Stimulation ◽  
Angular Rotation ◽  
Straight Line ◽  
Before And After ◽  
Fixed Reference ◽  
Behavioural Experiments ◽  
Triangle Completion ◽  
Subjective Discomfort ◽  
Magnetic North

Spatial orientation and navigation depend primarily on vision. Blind people lack this critical source of information. To facilitate wayfinding and to increase the feeling of safety for these people, the “feelSpace belt” was developed. The belt signals magnetic north as a fixed reference frame via vibrotactile stimulation. This study investigates the effect of the belt on typical orientation and navigation tasks and evaluates the emotional impact. Eleven blind subjects wore the belt daily for seven weeks. Before, during and after the study period, they filled in questionnaires to document their experiences. A small sub-group of the subjects took part in behavioural experiments before and after four weeks of training, i.e., a straight-line walking task to evaluate the belt’s effect on keeping a straight heading, an angular rotation task to examine effects on egocentric orientation, and a triangle completion navigation task to test the ability to take shortcuts. The belt reduced subjective discomfort and increased confidence during navigation. Additionally, the participants felt safer wearing the belt in various outdoor situations. Furthermore, the behavioural tasks point towards an intuitive comprehension of the belt. Altogether, the blind participants benefited from the vibrotactile belt as an assistive technology in challenging everyday situations.

scholarly journals The effect of step size on straight-line orientation

2019 ◽  
Vol 16 (157) ◽  
pp. 20190181 ◽  
Author(s):  
Lana Khaldy ◽  
Orit Peleg ◽  
Claudia Tocco ◽  
L. Mahadevan ◽  
Marcus Byrne ◽  
...  
Keyword(s):  
Sensory Information ◽  
Dung Beetles ◽  
Line Orientation ◽  
Step Size ◽  
Directional Information ◽  
Straight Path ◽  
Directional Error ◽  
Straight Line ◽  
Motor Error ◽  
Orientation Cues

Moving along a straight path is a surprisingly difficult task. This is because, with each ensuing step, noise is generated in the motor and sensory systems, causing the animal to deviate from its intended route. When relying solely on internal sensory information to correct for this noise, the directional error generated with each stride accumulates, ultimately leading to a curved path. In contrast, external compass cues effectively allow the animal to correct for errors in its bearing. Here, we studied straight-line orientation in two different sized dung beetles. This allowed us to characterize and model the size of the directional error generated with each step, in the absence of external visual compass cues ( motor error ) as well as in the presence of these cues ( compass and motor errors ). In addition, we model how dung beetles balance the influence of internal and external orientation cues as they orient along straight paths under the open sky. We conclude that the directional error that unavoidably accumulates as the beetle travels is inversely proportional to the step size of the insect, and that both beetle species weigh the two sources of directional information in a similar fashion.

scholarly journals Mobile EEG identifies the re-allocation of attention during real-world activity

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Simon Ladouce ◽  
David I. Donaldson ◽  
Paul A. Dudchenko ◽  
Magdalena Ietswaart
Keyword(s):  
Cognitive Processing ◽  
Sensory Processing ◽  
Real World ◽  
Event Related Potential ◽  
Limited Resources ◽  
Attentional Resources ◽  
Processing Demands ◽  
Neural Marker ◽  
Per Se ◽  
Human Participants

Abstract The distribution of attention between competing processing demands can have dramatic real-world consequences, however little is known about how limited attentional resources are distributed during real-world behaviour. Here we employ mobile EEG to characterise the allocation of attention across multiple sensory-cognitive processing demands during naturalistic movement. We used a neural marker of attention, the Event-Related Potential (ERP) P300 effect, to show that attention to targets is reduced when human participants walk compared to when they stand still. In a second experiment, we show that this reduction in attention is not caused by the act of walking per se. A third experiment identified the independent processing demands driving reduced attention to target stimuli during motion. ERP data reveals that the reduction in attention seen during walking reflects the linear and additive sum of the processing demands produced by visual and inertial stimulation. The mobile cognition approach used here shows how limited resources are precisely re-allocated according to the sensory processing demands that occur during real-world behaviour.

The Discrimination of Dynamic Orientation Changes in Gratings

Perception ◽  
1995 ◽  
Vol 24 (6) ◽  
pp. 665-679 ◽  
Author(s):  
Michael J Wright ◽  
Kevin N Gurney
Keyword(s):  
Spatial Frequency ◽  
Visual Memory ◽  
Frequency Function ◽  
Short Isis ◽  
Angular Rotation ◽  
Spatial Frequencies ◽  
Straight Line ◽  
Order Of Magnitude ◽  
Data Points ◽  
Best Fitting

Thresholds were measured for discrimination of direction of a step angular rotation of gratings. The addition of simultaneous phase displacements (translation) had little effect on rotation thresholds for gratings over a considerable range; discrimination of rotation is unaffected by random directional translations an order of magnitude larger. Angular rotation discrimination thresholds increased with interstimulus interval (ISI). Thus discrimination is based at short ISIs (180 ms or less) on a percept of rotary motion, but at ISIs of several seconds by a spatial strategy (comparing static component orientations) relying on visual memory. Data points for the short-ISI region fell below the best-fitting straight line, and the slope of the short-ISI region of the curve was steeper than that of the long-ISI region. However, when either compound or simple gratings with uncorrelated spatial frequencies were used in the two stimulus frames, there was no evidence for a separate function at short ISIs. Orientation-change thresholds were measured for simple gratings as a function of contrast and spatial frequency. The contrast function showed saturation and the spatial frequency function was U-shaped. Rotation sensitivity for gratings is thus similar in its spatiotemporal properties to translation sensitivity. The findings support the proposal that rotation discrimination (at short ISIs) is achieved by a template mechanism combining signals from different directional detectors, rather than by cognitive comparison of the outputs of the directional mechanisms themselves.

scholarly journals Vestibular Loss in Older Adults Is Associated with Impaired Spatial Navigation: Data from the Triangle Completion Task

2017 ◽  
Vol 8 ◽  
Author(s):  
Yanjun Xie ◽  
Robin T. Bigelow ◽  
Scott F. Frankenthaler ◽  
Stephanie A. Studenski ◽  
Scott D. Moffat ◽  
...  
Keyword(s):  
Older Adults ◽  
Spatial Navigation ◽  
Vestibular Loss ◽  
Navigation Data ◽  
Completion Task ◽  
Triangle Completion

scholarly journals Testing models of path integration in a triangle completion task

2010 ◽  
Vol 8 (6) ◽  
pp. 1153-1153 ◽  
Author(s):  
E. Chrastil ◽  
W. Warren
Keyword(s):  
Path Integration ◽  
Completion Task ◽  
Triangle Completion

Homing in Virtual Environments: Effects of Field of View and Path Layout

Perception ◽  
1997 ◽  
Vol 26 (3) ◽  
pp. 301-311 ◽  
Author(s):  
Patrick Péruch ◽  
Mark May ◽  
Fredrik Wartenberg
Keyword(s):  
Spatial Information ◽  
Three Dimensional ◽  
Spatial Knowledge ◽  
Information Coding ◽  
Directional Information ◽  
Turning Angle ◽  
Simulated Environments ◽  
Starting Point ◽  
Homogeneous Set ◽  
Triangle Completion

Triangle completion (ie homing to the starting point after completing two legs of a triangle) is a widely used method for examining path-integration abilities in animals and humans. Two experiments are reported in which homing was used to examine the efficiency of purely visual mechanisms (eg optical flow) for spatial-information coding and integration. Adult observers had to complete triangles in an interactively simulated three-dimensional environment which consisted of two critical objects and a homogeneous set of white cylinders serving as background. Each participant completed twenty-seven triangles corresponding to a factorial combination of three geometrical fields of view (40°, 60°, or 80°) and nine triangle layouts (with variations of the first turning angle and the second leg). Homing performances revealed strong effects of triangle layout, but no effect of geometrical fields of view: variations in the amount of simultaneous visible spatial information did not influence the acquisition of spatial knowledge in the environments used. Applying the encoding-error model to the data revealed severe systematic errors of picking up directional information while moving through visually simulated environments. These results are discussed with respect to informational differences between situations of purely visual and nonvisual navigations in space.

Vision and Haptics Share Spatial Attentional Resources and Visuotactile Integration Is Not Affected by High Attentional Load

2015 ◽  
Vol 28 (3-4) ◽  
pp. 371-392 ◽  
Author(s):  
Basil Wahn ◽  
Basil Wahn ◽  
Peter König
Keyword(s):  
Dual Task ◽  
Spatial Information ◽  
Sensory Modality ◽  
Human Information Processing ◽  
Visual Modality ◽  
Task Condition ◽  
Dual Task Condition ◽  
Single Task ◽  
Attentional Resources ◽  
Attentional Load

Human information processing is limited by attentional resources. Two questions that are discussed in multisensory research are (1) whether there are separate spatial attentional resources for each sensory modality and (2) whether multisensory integration is influenced by attentional load. We investigated these questions using a dual task paradigm: Participants performed two spatial tasks (a multiple object tracking [‘MOT’] task and a localization [‘LOC’] task) either separately (single task condition) or simultaneously (dual task condition). In the MOT task, participants visually tracked a small subset of several randomly moving objects. In the LOC task, participants either received visual, tactile, or redundant visual and tactile location cues. In the dual task condition, we found a substantial decrease in participants’ performance and an increase in participants’ mental effort (indicated by an increase in pupil size) relative to the single task condition. Importantly, participants performed equally well in the dual task condition regardless of whether they received visual, tactile, or redundant multisensory (visual and tactile) location cues in the LOC task. This result suggests that having spatial information coming from different modalities does not facilitate performance, thereby indicating shared spatial attentional resources for the tactile and visual modality. Also, we found that participants integrated redundant multisensory information optimally even when they experienced additional attentional load in the dual task condition. Overall, findings suggest that (1) spatial attentional resources for the tactile and visual modality overlap and that (2) the integration of spatial cues from these two modalities occurs at an early pre-attentive processing stage.

scholarly journals Attention Mediates the Effect of Context-Relevant Social

2015 ◽  
Vol 3 (3-4) ◽  
pp. 189-200 ◽  
Author(s):  
N. Srinivasan ◽  
S. Tewari ◽  
M. Makwana ◽  
N. P. Hopkins
Keyword(s):  
Social Meaning ◽  
Single Task ◽  
Attentional Resources ◽  
Attentional Load ◽  
Timing Task ◽  
The Social ◽  
Task Conditions ◽  
Religious Festival ◽  
The City

In everyday life we perceive events as having durations. Recent research suggests that the labeling of a stimulus influences the experience of its duration. Plausibly, the social meaning attributed to a stimulus impacts upon the amount of attention allocated to it, with greater attention resulting in better encoding and longer reproduction times. However, direct evidence for the role of attention in this effect of social meaning on duration reproduction is lacking. The present study addresses this issue directly. Eighty-four male Hindu pilgrims attending theKumbh Melain India listened to an ambiguous sound clip and reproduced its duration in a prospective timing task. The context-relevant social meaning of this sound clip was manipulated through attributing the sound to either the religious festival or busy city streets. Attentional load was manipulated by asking half the participants to perform a concurrent task. Reproduced durations were longer in the Mela compared to the City condition but only when participants completed a single task. The finding that mere labeling of the stimulus impacts duration judgments in a prospective paradigm in the single-task but not the dual-task conditions suggests that the effect of social meaning is indeed mediated through the deployment of attentional resources.

Sign in / Sign up

Export Citation Format

Share Document