scholarly journals The early but not the late neural correlate of auditory awareness is contralateral to auditory stimulation

2020 ◽  
Author(s):  
Rasmus Eklund ◽  
Billy Gerdfeldter ◽  
Stefan Wiens
Keyword(s):  
Critical Role ◽  
Auditory Stimulation ◽  
Neural Correlate ◽  
Somatosensory Stimulation ◽  
Late Positivity ◽  
Processing Theory ◽  
Recurrent Processing ◽  
Phenomenal Awareness ◽  
Early Activity ◽  
Support Research

Theories disagree as to whether it is the early or the late neural correlate of awareness plays a critical role in phenomenal awareness. According to recurrent processing theory, early activity in primary sensory areas should correspond closely to phenomenal awareness. In support, research with electroencephalography found that in the visual and somatosensory modality, an early neural correlate of awareness is contralateral to stimulation, whereas a late neural correlate of awareness does not appear to be lateralized. Thus, early activity is sensitive to the perceived location of visual and somatosensory stimulation. Critically, it is unresolved whether this is true also for hearing. In the present study (N = 26 students), we found that the early neural correlate of awareness (auditory awareness negativity, AAN) was contralateral to auditory stimulation, whereas the late (late positivity, LP) was not. Because these findings match those in the visual and somatosensory modalities, they suggest that recurrent processing theory is valid across modalities.

scholarly journals Neurobiology of mammalian olfactory learning that occurs during sensitive periods

2010 ◽  
Vol 56 (6) ◽  
pp. 819-833 ◽  
Author(s):  
Hideto Kaba
Keyword(s):  
Olfactory Bulb ◽  
Neural Plasticity ◽  
Critical Role ◽  
Olfactory Learning ◽  
Mitral Cells ◽  
Somatosensory Stimulation ◽  
Release Of Noradrenaline ◽  
Functional Changes ◽  
Sensitive Periods ◽  
Circuit Function

Abstract This review examines the organizational principles underlying olfactory learning in three specialized contexts that occur during sensitive periods of enhanced neural plasticity and emphasizes some of their common features. All three forms of olfactory learning are associated with neural changes in the olfactory bulb (OB) at the first stage of sensory processing. These changes require the association of the olfactory and somatosensory signals in the OB. They all depend on somatosensory stimulation- induced release of noradrenaline that induces structural and functional changes at mitral-granule cell reciprocal synapses in the OB, resulting in increases in inhibitory transmission. In the accessory olfactory bulb, this represents the enhanced self-inhibition of mitral cells, which selectively disrupts the transmission of the mating male's pregnancy-blocking signal at this level. In contrast, an extensive network of secondary dendrites of mitral cells in the main olfactory bulb probably results in a sharpening of the odor-induced pattern of activity, due to increases in lateral inhibition, leading to offspring recognition in sheep and neonatal learning in rats and rabbits. These findings show that inhibitory interneurons play a critical role in olfactory learning. Further work on how these neurons shape olfactory circuit function could provide important clues to understand memory functions of interneurons in other systems. Moreover, recent research has suggested that three forms of olfactory learning are controlled by synergistic, redundant, and distributed neural mechanisms. This has general implications regarding the mechanisms that may contribute to the robustness of memories.

scholarly journals Perception of invisible masked objects in early infancy

2021 ◽  
Vol 118 (27) ◽  
pp. e2103040118
Author(s):  
Yusuke Nakashima ◽  
So Kanazawa ◽  
Masami K. Yamaguchi
Keyword(s):  
Visual Perception ◽  
Visual Information ◽  
Critical Role ◽  
Early Infancy ◽  
First Year ◽  
Backward Masking ◽  
Feed Forward ◽  
Recurrent Processing ◽  
First Year Of Life ◽  
Visual Backward Masking

Recurrent loops in the visual cortex play a critical role in visual perception, which is likely not mediated by purely feed-forward pathways. However, the development of recurrent loops is poorly understood. The role of recurrent processing has been studied using visual backward masking, a perceptual phenomenon in which a visual stimulus is rendered invisible by a following mask, possibly because of the disruption of recurrent processing. Anatomical studies have reported that recurrent pathways are immature in early infancy. This raises the possibility that younger infants process visual information mainly in a feed-forward manner, and thus, they might be able to perceive visual stimuli that adults cannot see because of backward masking. Here, we show that infants under 7 mo of age are immune to visual backward masking and that masked stimuli remain visible to younger infants while older infants cannot perceive them. These results suggest that recurrent processing is immature in infants under 7 mo and that they are able to perceive objects even without recurrent processing. Our findings indicate that the algorithm for visual perception drastically changes in the second half of the first year of life.

scholarly journals V1 as an Egocentric Cognitive Map

2021 ◽  
Author(s):  
Paul Linton
Keyword(s):  
Cognitive Processing ◽  
Neural Correlates ◽  
Cognitive Map ◽  
Eye Position ◽  
Top Down ◽  
Processing Theory ◽  
Pictorial Cues ◽  
Recurrent Processing ◽  
Visual Consciousness ◽  
Integrated Information Theory

We typically distinguish between V1 as an egocentric perceptual map and the hippocampus as an allocentric cognitive map. In this article we explain why V1 also functions as an egocentric cognitive map. To the extent that cognitive processing has been discussed in V1, it has focused on (a) the allocation of attention, (b) top-down influences on perception, and (c) the transition from egocentric perception to allocentric navigation. By contrast, in this article we argue that three well-documented functions of V1, namely (a) the estimation of distance from eye position, (b) the estimation of size from eye position and/or pictorial cues, and (c) the multisensory integration of vision with proprioception and hearing, are potentially better understood as post-perceptual cognitive inferences. We use this insight to explore V1 as the neural correlates of the visual perception / cognition distinction, and propose a low-level account of visual consciousness in contrast to mid-level accounts (recurrent processing theory; integrated information theory), and higher-level accounts (higher-order thought; global workspace theory). We conclude by outlining the implications of our account for the perception of depth, motion, and colour / illumination.

scholarly journals Locked Collections: Copyright and the Future of Research Support

2017 ◽  
Author(s):  
D.R. Jones
Keyword(s):  
Academic Libraries ◽  
Critical Role ◽  
Institutions Of Higher Education ◽  
Research Support ◽  
Interlibrary Loan ◽  
System P ◽  
The Future ◽  
Agents Of Change ◽  
Scholarly Communication System ◽  
Support Research

Jones, D.R., Locked Collections: Copyright and the Future of Research Support, 105 Law Libr. J. 425 (2013). Researchers in institutions of higher education depend on access to the scholarly record, and academic libraries play a critical role in supporting this research. As academic collections shift to primarily electronic format, research support is in jeopardy. Copyright holders, through the use of licensing and contracts to control electronic works, limit or prohibit interlibrary loan and other means of research support. As predominantly digital library collections increase, libraries may find that they have locked collections. They will be unable to lend or to borrow. This article examines how increased reliance on e-collections impacts the ability of academic libraries to support research and explores and assesses various approaches to ensure research support. The article urges that libraries actively pursue agreements that reinforce their mission to support the creation, dissemination and preservation of knowledge. At the same time, libraries must be agents of change, serving as active participants in the transformation of the scholarly communication system.

scholarly journals Apical Amplification – A Cellular Mechanism of Conscious Perception?

2021 ◽  
Author(s):  
Tomas Marvan ◽  
Michal Polák ◽  
Talis Bachmann ◽  
William A. Phillips
Keyword(s):  
Perceptual Experience ◽  
Sensory Input ◽  
Conscious Experience ◽  
Cellular Mechanism ◽  
Conscious Perception ◽  
Context Sensitive ◽  
Processing Theory ◽  
Recurrent Processing ◽  
Theoretical View ◽  
Integrated Information Theory

We present a theoretical view of the cellular foundations fornetwork-level processes involved in producing our conscious experience.Inputs to apical synapses in layer 1 of a large subset of neocortical cellsare summed at an integration zone near the top of their apical trunk. Theseinputs come from diverse sources, and provide a context within which thetransmission of information abstracted from sensory input to their basal andperisomatic synapses can be amplified when relevant. We argue that apicalamplification (AA) enables conscious perceptual experience and makes it moreflexible, and thus more adaptive, by being sensitive to context. AA providesa possible mechanism for recurrent processing theory that avoids strongloops. It makes the broadcasting hypothesized by global neuronal workspacetheories feasible while preserving the distinct contributions of theindividual cells receiving the broadcast. It also provides mechanisms thatcontribute to the holistic aspects of integrated information theory. As AAis highly dependent on cholinergic, aminergic, and other neuromodulators, itrelates the specific contents of conscious experience to global mental statesand to fluctuations in arousal when awake. We conclude that apical dendritesprovide a cellular mechanism for the context-sensitive selectiveamplification that is a cardinal prerequisite of conscious perception.

scholarly journals V1 as an egocentric cognitive map

2021 ◽  
Vol 2021 (2) ◽  
Author(s):  
Paul Linton
Keyword(s):  
Visual Experience ◽  
Neural Correlates ◽  
Cognitive Map ◽  
Laminar Structure ◽  
Detection Thresholds ◽  
Processing Theory ◽  
Recurrent Processing ◽  
Visual Consciousness ◽  
Integrated Information Theory ◽  
Rule Out

Abstract We typically distinguish between V1 as an egocentric perceptual map and the hippocampus as an allocentric cognitive map. In this article, we argue that V1 also functions as a post-perceptual egocentric cognitive map. We argue that three well-documented functions of V1, namely (i) the estimation of distance, (ii) the estimation of size, and (iii) multisensory integration, are better understood as post-perceptual cognitive inferences. This argument has two important implications. First, we argue that V1 must function as the neural correlates of the visual perception/cognition distinction and suggest how this can be accommodated by V1’s laminar structure. Second, we use this insight to propose a low-level account of visual consciousness in contrast to mid-level accounts (recurrent processing theory; integrated information theory) and higher-level accounts (higher-order thought; global workspace theory). Detection thresholds have been traditionally used to rule out such an approach, but we explain why it is a mistake to equate visibility (and therefore the presence/absence of visual experience) with detection thresholds.

scholarly journals Exploring the Mitigating Effects of Early Somatosensory (Tactile) Stimulation and Acoustic Discrimination Experience in Neonatal Hypoxic-Ischemic Male Rats

2015 ◽  
Author(s):  
Patricia Taubin
Keyword(s):  
Spatial Memory ◽  
Beneficial Effect ◽  
Exploratory Behavior ◽  
Early Life ◽  
Tactile Stimulation ◽  
Auditory Stimulation ◽  
Brain Weight ◽  
Male Rats ◽  
Somatosensory Stimulation ◽  
Acoustic Discrimination

<p>The focus of this study was to determine the effects of early somatosensory (tactile) stimulation and acoustic discrimination experiences in hypoxic-ischemic (HI) male rats on long-term behaviors, learning sensory, and brain weight outcomes. 58 Wistar rats were randomly assigned to one of the three conditions: no stimulation, somatosensory stimulation and auditory stimulation. To observe the effects of the early life stimulation on adult behavioral measures, the following testing was performed: analysis of exploratory behavior, acoustic discrimination, spatial/memory learning, and brain weight. Overall we hypothesized that somatosensory and auditory interventions earlier in life would have beneficial effect on subjects’ performance in all the testing. Results suggested that tactile and auditory stimulation in early life did not have any significant beneficial effects on improving spatial learning, auditory processing or exploratory behavior in HI and sham subjects. However, some beneficial effect was found in the spatial memory task but only for the tactile HI and auditory sham group.</p>

scholarly journals Perception of invisible masked objects in early infancy

2021 ◽  
Author(s):  
Yusuke Nakashima ◽  
So Kanazawa ◽  
Masami K. Yamaguchi
Keyword(s):  
Visual Perception ◽  
Visual Information ◽  
Critical Role ◽  
Early Infancy ◽  
First Year ◽  
Backward Masking ◽  
Recurrent Processing ◽  
First Year Of Life ◽  
Visual Backward Masking

AbstractRecurrent loops in the visual cortex play a critical role in visual perception, which is likely not mediated by purely feedforward pathways. However, the development of recurrent loops is poorly understood. The role of recurrent processing has been studied using visual backward masking, a perceptual phenomenon in which a visual stimulus is rendered invisible by a following mask, possibly because of the disruption of recurrent processing. Anatomical studies have reported that recurrent pathways are immature in early infancy. This raises the possibility that younger infants process visual information mainly in a feedforward manner, and thus, they might be able to perceive visual stimuli that adults cannot see because of backward masking. Here, we show that infants under 7 months of age are immune to visual backward masking and that masked stimuli remain visible to younger infants while older infants cannot perceive them. These results suggest that recurrent processing is immature in infants under 7 months and that they are able to perceive objects even without recurrent processing. Our findings indicate that the algorithm for visual perception drastically changes in the second half of the first year of life.

scholarly journals The relationship between attention and consciousness: an expanded taxonomy and implications for ‘no-report’ paradigms

2018 ◽  
Vol 373 (1755) ◽  
pp. 20170348 ◽  
Author(s):  
Michael A. Pitts ◽  
Lydia A. Lutsyshyna ◽  
Steven A. Hillyard
Keyword(s):  
Sensory Processing ◽  
Cognitive Neuroscience ◽  
Future Research ◽  
Perceptual Awareness ◽  
Neural Basis ◽  
Processing Theory ◽  
Cognitive Access ◽  
Recurrent Processing ◽  
The Relationship ◽  
Integrated Information Theory

Tensions between global neuronal workspace theory and recurrent processing theory have sparked much debate in the field of consciousness research. Here, we focus on one of the key distinctions between these theories: the proposed relationship between attention and consciousness. By reviewing recent empirical evidence, we argue that both theories contain key insights and that certain aspects of each theory can be reconciled into a novel framework that may help guide future research. Alternative theories are also considered, including attended intermediate-level representations theory, integrated information theory and higher order thought theory. With the aim of offering a fresh and nuanced perspective to current theoretical debates, an updated taxonomy of conscious and non-conscious states is proposed. This framework maps a wider spectrum of conscious states by incorporating contemporary views from cognitive neuroscience regarding the variety of attentional mechanisms that are known to interact with sensory processing. Whether certain types of attention are necessary for phenomenal and access consciousness is considered and incorporated into this extended taxonomy. To navigate this expanded space, we review recent ‘no-report’ paradigms and address several methodological misunderstandings in order to pave a clear path forward for identifying the neural basis of perceptual awareness. This article is part of the theme issue ‘Perceptual consciousness and cognitive access'.

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