Covert attention increases contrast sensitivity: psychophysical, neurophysiological and neuroimaging studies
Section snippets
Limited resources
Each time we open our eyes we are confronted with an overwhelming amount of information. Despite this fact, we have the clear impression of understanding what we see. This requires selecting relevant information out of the irrelevant noise, selecting the wheat from the chaff. In Funes el Memorioso [Funes the Memoirist], Borges suggests that forgetting is what enables remembering and thinking; in perception, ignoring irrelevant information is what makes it possible for us to attend and interpret
Effects of transient attention on early vision
Much research has focused on the time course and degree of automaticity of the allocation of sustained and transient attention. However, less is known about the ways in which these systems, in particular sustained attention, affect fundamental visual dimensions. In past research, my laboratory has been particularly interested in characterizing the effects of transient attention on early visual processes. Given that transient attention highlights salient changes in the environment, its default,
Neurophysiological studies of attentional modulation of apparent stimulus contrast: attentional facilitation and selection
The development of techniques to record the activity of neurons in awake-behaving animals has enabled researchers to probe the biological foundations of sustained attention. Single-unit recording studies in the monkey have provided detailed, quantitative descriptions of how attention alters visual cortical neuron responses.
A number of neurophysiological studies have shown that directing attention to a stimulus increases neuronal sensitivity, so that neurons respond to an attended stimulus much
Transient attention enhances perceptual performance and fMRI response in human visual cortex
Studies on brain mechanisms of attention have mostly examined sustained attention, and some of them have characterized its effects on stimulus processing in the visual cortex. For instance, in single-unit recording studies, researchers have learned that sustained attention can reduce external noise by reducing the influence of unattended stimuli (Moran and Desimone, 1985; Luck et al., 1997) and that it can also boost the signal by increasing the effective stimulus contrast (Reynolds et al., 2000
Conclusion
As remarkable as the human visual and cognitive systems may be, inevitably we are still limited by both bandwidth and processing power. There is a fixed amount of overall energy consumption available to the brain, and the cost of cortical computation is high. Attention is crucial in optimizing the systems’ limited resources.
This chapter has focused on the effects of spatial attention on contrast sensitivity, for which the best mechanistic understanding of visual attention has been achieved due
Acknowledgments
We thank the past and present lab members, in particular Leslie Cameron, Sam Ling, Taosheng Liu, Cigdem Penpeci-Talgar, and Franco Pestilli, coauthors in the psychophysical and neuroimaging research described here, to Stuart Fuller, Sam Ling, Taosheng Liu, and Franco Pestilli, for helpful comments on this manuscript, and to John Reynolds and Stephan Treue for allowing us to reprint figures from their papers.
References (156)
- et al.
Feature-based integration of orientation signals in visual search
Vision Res.
(2000) - et al.
Visual attention
Vision Res.
(2004) - et al.
Effects of spatial attention on detection and identification of oriented lines
Acta Psychol. (Amst),
(2002) - et al.
Neuronal basis of contrast discrimination
Vision Res.
(1999) - et al.
Covert attention affects the psychometric function of contrast sensitivity
Vision Res.
(2002) Transient covert attention increases contrast sensitivity and spatial resolution: support for signal enhancement
- et al.
Spatial covert attention increases contrast sensitivity across the CSF: support for signal enhancement
Vision Res.
(2000) - et al.
Automatic gain control contrast mechanisms are modulated by attention in humans: evidence from visual evoked potentials
Vision Res.
(2001) - et al.
Mechanisms of perceptual attention in precuing of location
Vision Res.
(2000) - et al.
The spatial distribution of visual attention
Vision Res.
(2004)
Improvement of visual acuity by spatial cueing: a comparative study in human and non-human primates
Vision Res.
Focal visual attention produces illusory temporal order and motion sensation
Vision Res.
Attentional effects on contrast discrimination in humans: evidence for both contrast gain and response gain
Vision Res.
Attention modulates contextual influences in the primary visual cortex of alert monkeys
Neuron
Models of bottom-up attention and saliency
Luminance and spatial attention effects on early visual processing
Brain Res. Cogn. Brain Res.
Increased activity in human visual cortex during directed attention in the absence of visual stimulation
Neuron
Spatial vision thresholds in the near absence of attention
Vision Res.
The cost of cortical computation
Curr. Biol.
Transient attention enhances perceptual performance and FMRI response in human visual cortex
Neuron
External noise distinguishes attention mechanisms
Vision Res.
The role of spatial frequency channels in letter identification
Vision Res.
Attentional modulation strength in cortical area MT depends on stimulus contrast
Neuron
The role of attention in the preparation of visually guided saccadic eye movements in man
Different attentional resources modulate the gain mechanisms for color and luminance contrast
Vision Res.
Effect of spatial selective attention on the steady-state visual evoked potential in the 20–28 Hz range
Brain Res. Cogn. Brain Res.
Contrast discrimination with and without spatial uncertainty
Vision Res.
Sustained and transient components of focal visual attention
Vision Res.
Set-size effects in visual search: the effect of attention is independent of the stimulus for simple tasks
Vision Res.
The psychophysics of visual search
Vision Res.
Visual cortex neurons in monkey and cat: effect of contrast on the spatial and temporal phase transfer functions
Vis. Neurosci.
An energy budget for signaling in the grey matter of the brain
J. Cereb. Blood Flow. Metab.
Comparing integration rules in visual search
J. Vis.
Single units and sensation: a neuron doctrine for perceptual psychology?
Perception
Enhancement of perceptual sensitivity as the result of selectively attending to spatial locations
Percept. Psychophys.
A physiological correlate of the ‘spotlight’ of visual attention
Nat. Neurosci.
The analysis of visual motion: a comparison of neuronal and psychophysical performance
J. Neurosci.
Signal detection theory applied to three visual search tasks: identification, yes/no detection and localization
Spat. Vis.
Linearity and normalization in simple cells of the macaque primary visual cortex
J. Neurosci.
Temporal performance fields: visual and attentional factors
Vision Res.
Attention alters appearance
Nat. Neurosci.
Covert attention accelerates the rate of visual information processing
Proc. Natl. Acad. Sci. USA
Characterizing visual performance fields: effects of transient covert attention, spatial frequency, eccentricity, task and set size
Spat. Vis.
Covert attention increases spatial resolution with or without masks: support for signal enhancement
J. Vis.
The contribution of covert attention to the set-size and eccentricity effects in visual search
J. Exp. Psychol. Hum. Percept. Perform.
Central and peripheral precuing of forced-choice discrimination
Q. J. Exp. Psychol. A
Responses of neurons in macaque area V4 during memory-guided visual search
Cereb. Cortex
Responses of neurons in inferior temporal cortex during memory-guided visual search
J. Neurophysiol.
A neural basis for visual search in inferior temporal cortex
Nature
Absolute threshold: analysis in terms of uncertainty
J. Opt. Soc. Am.
Cited by (142)
Emergent human-like covert attention in feedforward convolutional neural networks
2024, Current BiologyRelationship between long-term recreational video gaming and visual processing
2022, Entertainment ComputingAttentional eye selection modulates sensory eye dominance
2021, Vision ResearchCitation Excerpt :Assuming that short-term monocular deprivation exclusively alters binocular interactions (Wang et al., 2020), our results reinforce the notion that changes in monocular attention, can produce shifts in eye balance (Wong, Baldwin, Hess, & Mullen, 2021). It has been well documented in both humans and other primates that spatial attention enhances neuronal responses in subcortical and early visual areas (e.g. Brefczynski & DeYoe, 1999; Carrasco, 2006; Heinze et al., 1994; Katyal & Ress, 2014; Luck et al., 1994; McAlonan, Cavanaugh, & Wurtz, 2008; Motter, 1993; O’Connor, Fukui, Pinsk, & Kastner, 2002; Reynolds, Chelazzi, & Desimone, 1999). This attentional modulation is thought to be accomplished by top-down feedback projections that increase contrast gain of the attended objects or regions (Reynolds & Chelazzi, 2004).
Modeling bottom-up and top-down attention with a neurodynamic model of V1
2020, Neurocomputing