95,794 research outputs found
Translations: effects of viewpoint, feature, naming and context on identifying repeatedly copied drawings
We explored the tension between bottom â up and top â down contributions to object recognition in a collaboration between a visual artist and a cognitive psychologist. Initial pictorial renderings of objects and animals from various viewpoints were iteratively copied, and a series of drawings that changed from highly concrete images into highly abstract images was produced. In drawing identification in which sets were shown in reverse order, participants were more accurate, more confident, and quicker to correctly identify the evolving image when it was originally displayed from a canonical viewpoint with all salient features present. In drawing identification in which images were shown in random order, more abstract images could be resolved as a result of previously identifying a more concrete iteration of the same drawing. The results raise issues about the influence of viewpoint and feature on the preservation of pictorial images and about the role of labelling in the interpretation of ambiguous stimuli. In addition, the study highlights a procedure in which visual stimuli can degrade without necessitating a substantial loss of complexity
Promoting Inclusivity in the Archive: A literature review reassessing tradition through theory and practice
The call for social justice and rise of postmodernism in the second half of the 20th century forced the critical re-evaluation of the traditional archive and its presumed neutral role in the collection and creation of history. Reappraisal of traditional archive theory and practice was forced by heightened critical conscious among the field and its constituents. This literature review examines contemporary methodologies and methods influenced by the postmodern movement and call for social justice in the archive. Affect theory, radical empathy, and queer/ed methodology provide new frameworks for the thinking about the archive space and work towards the creation of a more diverse and inclusive archive. The collection of oral histories and participatory, community archiving practices provide concrete methods for employing the aforementioned theories. This paper purports that these ideas may be better framed within the context of the post-postmodern movement of metamodernism and calls for the continual evaluation of archival theory and practice within this vein
An Overdensity of Extremely Red Objects Around Faint Mid-IR galaxies
We have searched for Extremely Red Objects (EROs) around faint mid-IR
selected galaxies in ELAIS fields. We find a significant overdensity, by
factors of 2 to 5, of these EROs compared to field EROs in the same region and
literature random field ERO counts. The excess is similar to that found
previously in the fields of known high redshift quasars and AGN. While with the
present data it cannot be definitely shown whether the overdensity is
physically connected to the mid-IR source, a derived radial distribution does
suggest this. The fraction of EROs among K-selected galaxies is high in the
mid-IR fields in agreement with the picture that the EROs responsible for the
overdensity are members of high redshift clusters of galaxies. We find R-K>5
selected EROs to be more clustered around the mid-IR galaxies than I-K>4 EROs,
though statistics are weak because of small numbers. However, this would be
consistent with a cluster/galaxy group scenario if, as we argue, the former
colour selection finds preferentially more strongly clustered early type
galaxies, whereas the latter selection includes a larger fraction of dusty
EROs. Finally, using the mid-IR data, we are able to limit the fraction of
ULIRG type very dusty EROs at K<18 magnitude to less than 10% of the total ERO
population.Comment: A&A, accepted, 13 pages and 5 ps-fig
Short term synaptic depression improves information transfer in perceptual multistability
Competitive neural networks are often used to model the dynamics of
perceptual bistability. Switching between percepts can occur through
fluctuations and/or a slow adaptive process. Here, we analyze switching
statistics in competitive networks with short term synaptic depression and
noise. We start by analyzing a ring model that yields spatially structured
solutions and complement this with a study of a space-free network whose
populations are coupled with mutual inhibition. Dominance times arising from
depression driven switching can be approximated using a separation of
timescales in the ring and space-free model. For purely noise-driven switching,
we use energy arguments to justify how dominance times are exponentially
related to input strength. We also show that a combination of depression and
noise generates realistic distributions of dominance times. Unimodal functions
of dominance times are more easily differentiated from one another using
Bayesian sampling, suggesting synaptic depression induced switching transfers
more information about stimuli than noise-driven switching. Finally, we analyze
a competitive network model of perceptual tristability, showing depression
generates a memory of previous percepts based on the ordering of percepts.Comment: 26 pages, 15 figure
How active perception and attractor dynamics shape perceptual categorization: A computational model
We propose a computational model of perceptual categorization that fuses elements of grounded and sensorimotor theories of cognition with dynamic models of decision-making. We assume that category information consists in anticipated patterns of agentâenvironment interactions that can be elicited through overt or covert (simulated) eye movements, object manipulation, etc. This information is firstly encoded when category information is acquired, and then re-enacted during perceptual categorization. The perceptual categorization consists in a dynamic competition between attractors that encode the sensorimotor patterns typical of each category; action prediction success counts as ââevidenceââ for a given category and contributes to falling into the corresponding attractor. The evidence accumulation process is guided by an active perception loop, and the active exploration of objects (e.g., visual exploration) aims at eliciting expected sensorimotor patterns that count as evidence for the object category. We present a computational model incorporating these elements and describing action prediction, active perception, and attractor dynamics as key elements of perceptual categorizations. We test the model in three simulated perceptual categorization tasks, and we discuss its relevance for grounded and sensorimotor theories of cognition.Peer reviewe
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