Showing papers by "Rodrigo Quian Quiroga published in 2014"
TL;DR: The results show that EEG signatures related to cognitive behavior develop across spatially unconstrained exploration of natural scenes and provide a first step towards understanding the mechanisms of target detection during natural search.
96 citations
TL;DR: It is proposed that whereas the gamma phase locking reflects the activation of local networks encoding particular recognized stimuli, the theta phaselocking reflects a global activation that provides a temporal window for processing consciously perceived stimuli in the MTL.
62 citations
TL;DR: The aim of this paper is to evaluate the feasibility of an implantable platform with the capability to wirelessly transmit the neural signals and perform real-time on-site spike sorting, and computationally modelled a two-stage implementation.
58 citations
TL;DR: A behavioural front-end model is proposed to assess the impact of the design parameters (including signal-to-noise ratio, filter type/order, bandwidth, converter resolution/rate) on subsequent spike processing and reveals that although these designs have a wide variation in design parameters, the ultimate impact on spike processing performance is relatively low.
Abstract: In spike sorting systems, front-end electronics is a crucial pre-processing step that not only has a direct impact on detection and sorting accuracy, but also on power and silicon area In this work, a behavioural front-end model is proposed to assess the impact of the design parameters (including signal-to-noise ratio, filter type/order, bandwidth, converter resolution/rate) on subsequent spike processing Initial validation of the model is provided by applying a test stimulus to a hardware platform and comparing the measured circuit response to the expected from the behavioural model Our model is then used to demonstrate the effect of the Analogue Front-End (AFE) on subsequent spike processing by testing established spike detection and sorting methods on a selection of systems reported in the literature It is revealed that although these designs have a wide variation in design parameters (and thus also circuit complexity), the ultimate impact on spike processing performance is relatively low (10–15%) This can be used to inform the design of future systems to have an efficient AFE whilst also maintaining good processing performance
55 citations
TL;DR: It is found that the firing of MTL neurons closely followed the subjects’ perceptual decisions—i.e., recognizing one person or the other, as well as the response to the ambiguous images was similar to the one obtained when showing the pictures without morphing.
37 citations
TL;DR: This work argues in favor of implementing paradigms where different perceptual outputs are obtained using identical visual inputs, and proposes that the large disagreement in the field is partially explained by the fact that different studies report the neural correlates of different conscious processes in the brain.
Abstract: In the last decades, the neural correlates of consciousness (NCCs) have been explored using both invasive and non-invasive recordings by comparing the brain activity elicited by seen versus unseen visual stimuli (i.e., the contrastive analysis). Here, we review a selection of these studies and discuss a set of considerations to improve the search for the NCCs using the contrastive analysis. In particular, we first argue in favour of implementing paradigms where different perceptual outputs are obtained using identical visual inputs. Second, we propose that the large disagreement in the field -in terms of the dissimilar neural patterns proposed as NCCs- is partially explained by the fact that different studies report the neural correlates of different conscious processes in the brain. More specifically, we distinguish between the perceptual awareness of a visual stimulus, associated to a boost in object-selective neural assemblies, and a more elaborate process (contextual awareness) that we argue is reflected in the firing of concept neurons in the medial temporal lobe, triggering a rich representation of the context, associations, and memories linked to the specific stimulus.
16 citations