The Speed of Sight

  title={The Speed of Sight},
  author={Christian Keysers and D K Xiao and P. Fldik and David Ian Perrett},
  journal={Journal of Cognitive Neuroscience},
Macaque monkeys were presented with continuous rapid serial visual presentation (RSVP) sequences of unrelated naturalistic images at rates of 14-222 msec/image, while neurons that responded selectively to complex patterns (e.g., faces) were recorded in temporal cortex. Stimulus selectivity was preserved for 65 of these neurons even at surprisingly fast presentation rates (14 msec/image or 72 images/sec). Five human subjects were asked to detect or remember images under equivalent conditions… 

Robust Selectivity to Two-Object Images in Human Visual Cortex

Rapid serial visual presentation for the determination of neural selectivity in area STSa.

Out of sight but not out of mind: the neurophysiology of iconic memory in the superior temporal sulcus

For gaps of up to 93 ms between consecutive images, human observers and neurones in the temporal cortex of macaque monkeys were found to continue processing a stimulus as if it was still present on the screen, suggesting the continued firing of neurone cells in temporal cortex may underlie iconic memory.

Human single-neuron responses at the threshold of conscious recognition

The results suggest that neurons in the medial temporal lobe can reflect conscious recognition by “all-or-none” responses.

Discrete and continuous mechanisms of temporal selection in rapid visual streams

The authors report that the neural activity initially supports parallel processing of multiple stimuli around the target in ventral visual areas followed later by isolated activation of reported images in parietal areas.

Temporal dynamics of shape analysis in macaque visual area V2.

The results indicate that the information about stimulus shape evolves dynamically and relatively rapidly in V2 during static visual stimulation in ways that may contribute to form discrimination.

Decoding visual inputs from multiple neurons in the human temporal lobe.

We investigated the representation of visual inputs by multiple simultaneously recorded single neurons in the human medial temporal lobe, using their firing rates to infer which images were shown to

Encoding of Predictable and Unpredictable Stimuli by Inferior Temporal Cortical Neurons

Data suggest that macaque IT neurons represent less accurately predictable compared with unpredictable images, as indicated by the peak decoding accuracy for the standard compared with the random sequence.

Differences in onset latency of macaque inferotemporal neural responses to primate and non-primate faces.

To examine the possibility that response onset latencies carry information about complex object images, single-cell responses in the inferior temporal cortex of alert monkeys are recorded, while they viewed >1,000 object stimuli.



Rapid categorization of natural images by rhesus monkeys

Two rhesus macaques were tested on a categorization task in which they had to classify previously unseen photographs flashed for only 80 ms, and it is argued that this form of rapid visual categorization is fundamentally similar in both monkeys and humans.

Responses of neurons in inferior temporal cortex during memory-guided visual search.

The results support a "biased competition" model of attention, according to which objects in the visual field compete for representation in the cortex, and this competition is biased in favor of the behaviorally relevant object by virtue of "top-down" feedback from structures involved in working memory.

Speed of processing in the human visual system

Dynamics of orientation coding in area V1 of the awake primate.

It is suggested that orientation selectivity is primarily generated using feedforward mechanisms, including feedforward inhibition, which has the advantage of allowing orientation to be computed rapidly, and avoids the initially poorly selective neuronal responses that characterize processing involving recurrent loops.

Single units and conscious vision.

  • N. Logothetis
  • Biology, Psychology
    Philosophical transactions of the Royal Society of London. Series B, Biological sciences
  • 1998
A strikingly large number of neurons in the early visual areas remained active during the perceptual suppression of the stimulus, a finding suggesting that conscious visual perception might be mediated by only a subset of the cells exhibiting stimulus selective responses.

Neuronal correlates of visibility and invisibility in the primate visual system

The temporal characteristics of masking illusions in humans and corresponding neuronal responses in the primary visual cortex of awake and anesthetized monkeys are compared to suggest that, for targets that can be masked (those of short duration), the transient neuronal responses associated with onset and turning off of the target may be important in its visibility.

Cortical correlate of pattern backward masking.

It is shown that reliable discrimination of briefly presented shapes by single neurons depends on the temporal integration of the response, and provides direct neurophysiological evidence for the "interruption theory" of backward masking.

The detection of visual signals by macaque frontal eye field during masking

The results show that visual signals masked by light are not filtered out at early stages of visual processing; furthermore, the magnitude of early visual responses in prefrontal cortex predicts the behavioral report.