Visual search

Like many other animals, humans direct their gaze to selectively sample the visual space based on task demands. Visual search, the process of locating an item among several visually presented objects, is a key paradigm in studying visual attention. While much is known about the brain networks underlying visual search, our understanding of the neural computations driving this behavior is limited. Simulating this behavior in-silico can provide a tool for developing and testing hypotheses about these neural computations. To address this gap, we trained an image-computable artificial neural networ

Visual search, the act of finding a target among multiple visually presented items, is a key paradigm in studying visual attention. While much is known about the brain networks underlying visual search, our understanding of the neural computations driving this behavior is limited, resulting in challenges in simulating such behavior in-silico. To address this gap, we developed an image-computable general-architecture visual search model (GVSM). We trained an artificial neural network to perform naturalistic visual search [Fig. A-B] using the same stimulus configuration as human psychophysics ex

…Understanding the mechanisms of visual perception is of particular relevance to conditions such as autism spectrum conditions, where differences in sensory perception are a core feature. Here we exploit the high resolution of 7-Tesla Magnetic Resonance Spectroscopy (MRS) to investigate the links between occipital GABA, autistic traits, and perceptual choice in humans. 45 participants (22 Female: 23 Male), aged 19-39 years, completed the Autism Spectrum Quotient questionnaire

The Inhibition of Return (IOR) is an orienting mechanism to visual or auditory stimuli. It facilitates visual search in crowded scenes by inhibiting inspection of previously searched locations and promote inspection of previously unsearched locations (Klein, 2000). In general, the reaction time (RT) toward a target is fast when the interval between cue and target is short and slow when the interval between cue and target is long. IOR is identified by the crossover point of the RT towards cued and un-cued targets. Aging (Madden, 2007), stressors (Yu et al., 2015), and auditory stimuli (Tang et

Visual search involves scanning the surroundings to find objects of interest amidst a clutter of irrelevant distractors. A commonly accepted theory proposes that pop out visual search is governed by a winner-take-all (WTA) competition between contextually modulated cells that form a saliency map. Yet, research indicates that WTA's capacity to gather information even from large populations, has limitations, casting doubt on its role in pop out visual search. In our investigation, we performed a modeling study to assess the accuracy of WTA in detecting the distinctive object in a pop out task. W

The talk will give a tour of Guided Search 6.0 (GS6), the latest evolution of the Guided Search model of visual search. Part 1 describes The Mechanics of Search. Because we cannot recognize more than a few items at a time, selective attention is used to prioritize items for processing. Selective attention to an item allows its features to be bound together into a representation that can be matched to a target template in memory or rejected as a distractor. The binding and recognition of an attended object is modeled as a diffusion process taking > 150 msec/item. Since selection occurs more fre

A striking range of individual differences has been reported in a variety of visual search tasks, which naturally leads to the idea that some people are better at finding things than others. However, this conclusion appears to be premature. We carried out a replication of three recent visual search experiments and found that each task showed a wide range of individual differences as predicted, and observed good test-retest reliability in all three. However, performance on any one task was not correlated with the performance in the others: participants who naturally adopt efficient search strat

Visual attention refers to a set of processes allowing selection of relevant and filtering out of irrelevant information in the visual environment. A large amount of research on visual attention has involved visual search paradigms, where observers are asked to report whether a single target is present or absent. However, recent studies have revealed that these classic single-target visual search tasks only provide a snapshot of how attention is allocated in the visual environment, and that multitarget visual foraging tasks may capture the dynamics visual attention more accurately. In visual f

…can be actively achieved by the visual system through global serial dependencies, a special kind of serial dependence between summary statistical representations. Serial dependence occurs also between emotional expressions, but it is highly selective for the same identity. Ov