3,278 research outputs found
The Search for Consciousness
In recent years, rapid technological developments in the field of neuroimaging have provided new methods for assessing residual cognition, detecting consciousness, and even communicating with patients who clinically appear to be in a vegetative state. Here, I highlight some of the major implications of these developments, discuss their scientific, clinical, legal, and ethical relevance, and make my own recommendations for future directions in this field
Beyond swarm intelligence: The Ultraswarm
This paper explores the idea that it may be possible to
combine two ideas – UAV flocking, and wireless cluster
computing – in a single system, the UltraSwarm. The
possible advantages of such a system are considered, and
solutions to some of the technical problems are identified.
Initial work on constructing such a system based around
miniature electric helicopters is described
Working Memory: Imaging the Magic Number Four
AbstractMany brain regions have been implicated in memory performance, but the relationship between memory capacity and neural activity has not been clear. Recent studies show that activity in the posterior parietal cortex increases with working memory load, implicating this region in the storage of representations in visual memory
The cost of space independence in P300-BCI spellers.
Background: Though non-invasive EEG-based Brain Computer Interfaces (BCI) have been researched extensively over the last two decades, most designs require control of spatial attention and/or gaze on the part of the user.
Methods: In healthy adults, we compared the offline performance of a space-independent P300-based BCI for spelling words using Rapid Serial Visual Presentation (RSVP), to the well-known space-dependent Matrix P300 speller.
Results: EEG classifiability with the RSVP speller was as good as with the Matrix speller. While the Matrix speller’s performance was significantly reliant on early, gaze-dependent Visual Evoked Potentials (VEPs), the RSVP speller depended only on the space-independent P300b. However, there was a cost to true spatial independence: the RSVP
speller was less efficient in terms of spelling speed.
Conclusions: The advantage of space independence in the RSVP speller was concomitant with a marked reduction in spelling efficiency. Nevertheless, with key improvements to the RSVP design, truly space-independent BCIs could approach efficiencies on par with the Matrix speller. With sufficiently high letter spelling rates fused with predictive
language modelling, they would be viable for potential applications with patients unable to direct overt visual gaze or covert attentional focus
Lattice baryon spectroscopy with multi-particle interpolators
In 2 + 1 flavour lattice QCD the spectrum of the nucleon is presented for
both parities using local meson-baryon type interpolating fields in addition to
the standard three-quark nucleon interpolators. The role of local five-quark
operators in extracting the nucleon excited state spectrum via correlation
matrix techniques is explored on dynamical gauge fields with = 293 MeV,
leading to the observation of a state consistent with the S-wave
scattering threshold in the negative-parity sector. Furthermore, the robustness
of the variational technique is examined by studying the spectrum on a variety
of operator bases. Fitting a single-state ansatz to the eigenstate-projected
correlators provides robust energies for the low-lying spectrum that are
essentially invariant despite being extracted from qualitatively different
bases.Comment: 13 Pages, 12 Figures, Updated version as appears in PR
Turning the other lobe: : Directional biases in brain diagrams
© 2017 The Author(s). This article is distributed under the terms of the Creative Commons Attribution 3.0 License (http://www.creativecommons.org/licenses/by/3.0/) which permits any use, reproduction and distribution of the work without further permission provided the original work is attributed as specified on the SAGE and Open Access pages (https://us.sagepub.com/en-us/nam/open-access-at-sage).Past research shows that in drawn or photographic portraits, people are significantly more likely to be posed facing to their right than their left. We examined whether the same type of bias exists among sagittal images of the human brain. An exhaustive search of Google images using the term 'brain sagittal view' yielded 425 images of a left or right facing brain. The direction of each image was coded and revealed that 80% of the brains were right-facing. This bias was present in images that did not contain any representation of a human head. It is argued that the effect might be aesthetic in nature, the result of the Western tradition of reading left to right or due to the facial factors that underlie the bias previously found in portraits.Peer reviewe
Temperamental variation in learned irrelevance in humans
BACKGROUND Learned irrelevance (LIRR) represents one of the mechanisms of attentional set-shifting and refers to the inability to attend to, or to learn about, any aspect of a stimulus previously experienced as irrelevant. Although it has been extensively studied in the context of clinical populations, not much is known about LIRR effects in relation to normal variation in individual differences. The present study was designed to assess how temperamental factors may modulate LIRR. PARTICIPANTS AND PROCEDURES Sixty-eight healthy volunteers performed a visual discrimination learning task modelled after Wisconsin Card Sorting Test. To test the susceptibility to learned irrelevance, participants were expected to shift their attention either to a dimension that prior to the extra-dimensional shift was completely irrelevant, or to a dimension that was previously partly correlated with reinforcement. Temperamental traits were assessed using the Formal Characteristics of Behaviour-Temperament Inventory (Zawadzki & Strelau, 1997). Intelligence level was stratified according to Raven\u27s Advanced Progressive Matrices (Raven, Raven, & Court, 2003). RESULTS Low level of Briskness and high level of Perseverance were related to enhanced susceptibility to LIRR. High levels of Activity and Emotional Reactivity were related to the poorer performance on the extra-dimensional set-shifting. No effects of other temperament characteristics or intelligence on LIRR were observed. CONCLUSIONS The results confirm a strong variation in LIRR related to individual differences in temperament, which appears to be unrelated to DA function. Our results highlight the importance of considering individual differences in studies on cognitive control
- …