Fast perceptual learning in visual hyperacuity.

  title={Fast perceptual learning in visual hyperacuity.},
  author={Tomaso A. Poggio and Manfred Fahle and Shimon Edelman},
  volume={256 5059},
In many different spatial discrimination tasks, such as in determining the sign of the offset in a vernier stimulus, the human visual system exhibits hyperacuity by evaluating spatial relations with the precision of a fraction of a photoreceptor's diameter. It is proposed that this impressive performance depends in part on a fast learning process that uses relatively few examples and that occurs at an early processing stage in the visual pathway. This hypothesis is given support by the… 

Models of Perceptual Learning in Vernier Hyperacuity

A biologically plausible extension of the HyperBF model is developed that takes into account basic features of the functional architecture of early vision and results of psychophysical experiments are reported that are consistent with the hypothesis that activity-dependent presynaptic amplification may be involved in perceptual learning in hyperacuity.

Fast perceptual learning in hyperacuity

Perceptual Learning in a Nonretinotopic Frame of Reference

This study uses a novel masking paradigm in which the offset in an invisible, oblique vernier stimulus was perceived in an aligned vertical or horizontal flanking stimulus presented at a different location, and proposes that perceptual learning involves changes in nonretinotopic, attentional readout processes.

Perceptual learning in visual hyperacuity: A reweighting model

No transfer of perceptual learning between similar stimuli in the same retinal position

Perceptual learning: a case for early selection.

  • M. Fahle
  • Psychology, Biology
    Journal of vision
  • 2004
In summary, perceptual learning seems to rely at least partly on changes on a relatively early level of cortical information processing (early selection), such as the primary visual cortex under the influence of top-down influences (selection and shaping).

Human Pattern Recognition: Parallel Processing and Perceptual Learning

  • M. Fahle
  • Biology, Psychology
  • 1994
The hypothesis that vernier breaks are detected ‘early’ during pattern recognition is supported by the fact that reaction times for the detection of verniers depend hardly at all on the number of stimuli presented simultaneously, indicating that deviation from straightness is an elementary feature for visual pattern recognition in humans that is detected at an early stage of pattern recognition.

Perceptual learning in visual search: Fast, enduring, but non-specific

Specificity of learning curvature, orientation, and vernier discriminations

  • M. Fahle
  • Biology, Psychology
    Vision Research
  • 1997

A quantitative measure for short-term cortical plasticity in human vision

This work studied spatial localization around an artificial scotoma, a small mask that occludes part of the visual field while a dynamic pattern is shown over a surrounding region, and found that the ability to determine the position of short line segments was strongly biased toward the interior of the scotomas.



Perceptual learning specific for orientation and spatial frequency

An experiment on perceptual learning in the discrimination of gratings of different waveform shows that learning is specific for both the orientation and the spatial frequency of the practice stimulus.

Where practice makes perfect in texture discrimination: evidence for primary visual cortex plasticity.

  • A. KarniD. Sagi
  • Biology, Psychology
    Proceedings of the National Academy of Sciences of the United States of America
  • 1991
This work reports remarkable long-term learning in a simple texture discrimination task where learning is specific for retinal input and suggests that learning involves experience-dependent changes at a level of the visual system where monocularity and the retinotopic organization of thevisual input are still retained and where different orientations are processed separately.

The effect of training on visual alignment discrimination and grating resolution

The results are interpreted to indicate that the neural mechanisms underlying three-point alignment and grating discrimination, like those for gap bisection, are not malleable to any significant extent.

Orientation-Specific Learning in Stereopsis

The stereoscopic skill that has been acquired may be specific to those orientation analysers that were stimulated during the training period, and there was a marked failure of transfer to a pattern whose elements had the opposed oblique orientation.

A cellular analogue of visual cortical plasticity

Neuronal activity plays an important role in the development of the visual pathway. The modulation of synaptic transmission by temporal correlation between pre- and postsynaptic activity is one

Improvement in vernier acuity with practice

The ability to detect small differences in the positions of two lines (vernier acuity) showed some improvement with practice in all eight subjects, even for subjects given no error feedback, and orientational differences present at the beginning of training diminished or disappeared with increased experience.

A specific and enduring improvement in visual motion discrimination.

Training improves the ability of human observers to discriminate between two similar directions of motion, specific to the direction on which an observer is trained, and it endures for several months.

A theory of how the brain might work.

  • T. Poggio
  • Computer Science
    Cold Spring Harbor symposia on quantitative biology
  • 1990
I propose a speculative new version of the grandmother cell theory to explain how the brain may work, discuss how the visual system may learn to recognize 3D objects, and relate our theory to

Learning representations by back-propagating errors

Back-propagation repeatedly adjusts the weights of the connections in the network so as to minimize a measure of the difference between the actual output vector of the net and the desired output vector, which helps to represent important features of the task domain.