Aspects Of Visual Cognition Research Articles

Differential Involvement of EEG Oscillatory Components in Sameness versus Spatial-Relation Visual Reasoning Tasks.

The development of deep convolutional neural networks (CNNs) has recently led to great successes in computer vision, and CNNs have become de facto computational models of vision. However, a growing body of work suggests that they exhibit critical limitations on tasks beyond image categorization. Here, we study one such fundamental limitation, concerning the judgment of whether two simultaneously presented items are the same or different (SD) compared with a baseline assessment of their spatial relationship (SR). In both human subjects and artificial neural networks, we test the prediction that SD tasks recruit additional cortical mechanisms which underlie critical aspects of visual cognition that are not explained by current computational models. We thus recorded electroencephalography (EEG) signals from human participants engaged in the same tasks as the computational models. Importantly, in humans the two tasks were matched in terms of difficulty by an adaptive psychometric procedure; yet, on top of a modulation of evoked potentials (EPs), our results revealed higher activity in the low β (16–24 Hz) band in the SD compared with the SR conditions. We surmise that these oscillations reflect the crucial involvement of additional mechanisms, such as working memory and attention, which are missing in current feed-forward CNNs.

Current practice and challenges in screening for visual perception deficits after stroke: a qualitative study

Purpose We document current clinical practice and needs in screening for visual perception problems after stroke to inform development of new screening tools. Materials and methods We interviewed 12 occupational therapists and 13 orthoptists. Interviews were thematically analysed using the Value Proposition Canvas, a model which establishes challenges and facilitators in what people want to achieve. Results Participants’ understanding of visual perception varied and often included sensory and cognitive deficits. Occupational therapists commonly screened for visual field deficits and hemispatial neglect, while other aspects of visual cognition were rarely assessed. A positive screening result triggered an orthoptic referral. Screening generally occurred during functional assessments and/or with in-house developed tools. Challenges to practice were: lack of time, lack of training, environmental and stroke survivor factors (e.g., aphasia), insufficient continuation of care, and test characteristics (e.g., not evidence-based). Facilitators were: quick and practical tools, experienced staff or tools with minimal training requirements, a streamlined care pathway. Conclusions Screening employs non-standardised assessments and rarely covers higher visual perceptual deficits. We demonstrates the need for an evidence-based visual perception screen, which should ideally be 15 min or less, be portable, and require minimal equipment. The screen should be suitable for bedside testing and aphasia-friendly. Implications for rehabilitation There is a high demand for training on what visual perception deficits are and how to screen for them. Building local relationships between orthoptists and occupational therapists is perceived as highly beneficial for providing good vision and visual perception care for stroke survivors. Occupational therapists should be alert for visual perceptual deficits in their patients preferably through systematic screening with standardised assessments such as the shortened version of the Rivermead Perceptual Assessment Battery or Occupational Therapy Adult Perceptual Screening Test.

Augmented reality powers a cognitive assistant for the blind.

To restore vision for the blind, several prosthetic approaches have been explored that convey raw images to the brain. So far, these schemes all suffer from a lack of bandwidth. An alternate approach would restore vision at the cognitive level, bypassing the need to convey sensory data. A wearable computer captures video and other data, extracts important scene knowledge, and conveys that to the user in compact form. Here, we implement an intuitive user interface for such a device using augmented reality: each object in the environment has a voice and communicates with the user on command. With minimal training, this system supports many aspects of visual cognition: obstacle avoidance, scene understanding, formation and recall of spatial memories, navigation. Blind subjects can traverse an unfamiliar multi-story building on their first attempt. To spur further development in this domain, we developed an open-source environment for standardized benchmarking of visual assistive devices.

A Pragmatic Oscillome: Aligning Visual Attentional Mechanisms with Language Comprehension.

A growing body of work over the last decade has investigated the potential functional role of neural oscillations in language comprehension (Giraud and Poeppel, 2012; Doelling and Poeppel, 2015; Lewis and Bastiaansen, 2015; Ding et al., 2016). I will explore how a number of recent developments in the field, and related domains of systems neuroscience, can generate much-needed linking hypotheses between the language sciences and neuroscience. To this end, I will focus on an area of linguistics whose existence has barely been acknowledged by the oscillation literature—pragmatics—and argue that elementary principles of discourse interpretation (though not more complex, peripheral aspects of pragmatic knowledge) can be implemented via generic, domain-general mechanisms elsewhere argued to be responsible for particular aspects of visual cognition. It will be suggested that these two systems share a number of striking computational/representational properties, and hence may share homologous dynamic and connectomic substrates.

Visualization, interpretation, and cognitive cybernetics

Interpretation of 3D seismic data involves the analysis and integration of many forms and derivatives of the original reflectivity data. This can lead to the generation of an overwhelming amount of data that can be difficult to use effectively when relying on conventional interpretation techniques. Our natural cognitive processes have evolved so that we can absorb and understand large amounts of complex data extremely quickly and effectively. However, these cognitive processes are heavily influenced by context and color perception. Seismic interpretation can benefit greatly through better exploiting the positive aspects of visual cognition and through techniques designed to minimize the pitfalls inherent in the cognitive process. The interpretation of data also requires the ability to combine data analysis with knowledge and expertise that is held by the interpreter. It is this combination of visual perception techniques to see the information, combined with interpreter guidance to understand what is seen, that makes interpretation of seismic data effective. Geological Expression workflows that are data driven and interpreter guided enable us to see and effectively interpret the geology that is present in the seismic data. In effect this gives us a Cognitive Interpretation of the data.

Neuroergonomics of Visual Cognition: Research and Applications

This panel examines recent developments in neuroergonomic research and application involving higher-order vision. Four important aspects of visual cognition are discussed, namely 3-D object motion, biological motion, visual memory, and visual imagery. Each of the panelists follows a neuroergonomic approach, first describing studies of these aspects of visual cognition using both behavioral and neuroimaging (fMRI, ERP, and MEG) measures. The implications of these results for human factors applications are then discussed. Particular domains of application that are examined include elder design, driving, virtual environments, and software and educational curriculum design.