A motion sequence may be represented as a single pattern in x–y–t space; a velocity of motion corresponds to a three-dimensional orientation in this space. Motion sinformation can be extracted by a system that responds to the oriented spatiotemporal energy. We discuss a class of models for human motion mechanisms in which the first stage consists of linear filters that are oriented in space-time and tuned in spatial frequency. The outputs of quadrature pairs of such filters are squared and summed to give a measure of motion energy. These responses are then fed into an opponent stage. Energy models can be built from elements that are consistent with known physiology and psychophysics, and they permit a qualitative understanding of a variety of motion phenomena.

/pdf/spatiotemporal-energy-models-for-the-perception-of-motion-43mzze32mc.pdf

Spatiotemporal energy models for the perception of motion

Vol. 1 1. Neural Basis of Vision. 2. Color Vision. 3. Depth Perception. 4. Perception of Visual Motion. 5. Perceptual Organization in Vision. 6. Attention. 7. Visual Object Recognition. 8. Motor Control. 9. Neural Basis of Audition. 10. Auditory Perception and Cognition. 11. Music Perception and Cognition. 12. Speech Perception. 13. Neural Basis of Haptic Perception. 14. Touch and Haptics. 15. Perception of Pain and Temperature. 16. Taste. 17. Olfaction. Vol. 2 1. Kinds of Memory. 2. Models of Memory. 3. Cognitive Neuroscience. 4. Spatial Cognition. 5. Knowledge Representation. 6. Psycholinguistics. 7. Language Processing. 8. Problem Solving. 9. Reasoning. 10. Decision Making. 11. Concepts & Categorization. 12. Cognitive Development. 13. Culture & Cognition. Vol. 3 1. Associative Structures in Pavlovian and Instrumental Conditioning. 2. Learning: Laws and Models of Basic Conditioning. 3. Reinforcement Learning. 4. Neural Analysis of Learning in Simple Systems. 5. Learning Mutants. 6. Learning Instincts. 7. Perceptual Learning. 8. Spatial Learning. 9. Temporal Learning. 10. Role of Learning in Cognitive Development. 11. Language Acquisition. 12. Role of Learning in the Operation of Motivational Systems. 13. Emotional Plasticity. 14. Anatomy of Motivation. 15. Hunger Energy Homeostasis. 16. Thirst and Water-Salt Appetite. 17. Reproductive Motivation. 18. Social Behavior. 19. Addiction. Vol. 4 1. Representational Measurement Theory. 2. Signal Detection Theory. 3. Psychophysical Scaling. 4. Cognitive Neuropsychology. 5. Functional Brain Imaging. 6. Neural Network Modeling. 7. Parallel and Serial Processing. 8. Methodology and Statistics in Single-Subject Experiments. 9. Analysis, Interpretation, and Visual Presentation of Experimental Data. 10. Meta-Analysis. 11. Mathematical Modeling. 12. Analysis of Response Time Distributions. 13. Testing and Measurement. 14. Personality and Individual Differences. 15. Electrophysiology of Attention. 16. Single vs. Multiple Systems of Memory and Learning. 17. Infant Cognition. 18. Aging and Cognition.

Stevens' handbook of experimental psychology

When a moving grating is viewed through an aperture, only motion orthogonal to its bars is visible, as motion parallel to the bars causes no change in the stimulus. Because there is a family of physical motions of various directions and speeds that appear identical, the motion of the grating is ambiguous. In contrast, when two crossed moving gratings are superimposed, the resulting plaid pattern usually moves unambiguously and predictably. In certain cases, however, two gratings do not combine into a single coherent percept, but appear to slide across one another. We have studied the conditions under which coherence does and does not occur, and we report here that it depends on the relative contrasts, spatial frequencies and directions of motion of the gratings. These effects may reveal the previously unstudied properties of a higher order stage of motion analysis.

/pdf/phenomenal-coherence-of-moving-visual-patterns-29l3vfllkz.pdf

Phenomenal coherence of moving visual patterns

The elaborated Reichardt detector (ERD) proposed by van Santen and Sperling [ J. Opt. Soc. Am. A1, 451 ( 1984)], based on Reichardt’s motion detector [ Z. Naturforsch. Teil B12, 447 ( 1957)], is an opponent system of two mirror-image subunits. Each subunit receives inputs from two spatiotemporal filters (receptive fields), multiplies the filter outputs, and temporally integrates the product. Subunit outputs are algebraically subtracted to yield ERD output. ERD’s can correctly indicate direction of motion of drifting sine waves of any spatial and temporal frequency. Here we prove that with a careful choice of either temporal or spatial filters, the subunits can themselves become quite similar or equivalent to the whole ERD; with suitably chosen filters, the ERD is equivalent to an elaborated version of a motion detector proposed by Watson and Ahumada [NASA Tech. Memo. 84352 (1983)]; and for every choice of filters, the ERD is fully equivalent to the detector proposed by Adelson and Bergen [ J. Opt. Soc. Am. A2, 284– 299 ( 1985)]. Some equivalences between the motion detection (in x, t) by ERD’s and spatial pattern detection (in x, y) are demonstrated. The responses of the ERD and its variants to drifting sinusoidal gratings, to other sinusoidally modulated stimuli (on–off gratings, counterphase flicker), and to combinations of sinusoids are derived and compared with data. ERD responses to two-frame motion displays are derived, and several new experimental predictions are tested experimentally. It is demonstrated that a system containing ERD’s of various sizes can solve the correspondence problem in two-frame motion of random-bar stimuli and shows the predicted phase dependencies when confronted with displays composed of triple sinusoids combined either in amplitude modulation phase or in quasi-frequency modulation phase. Finally, it is shown that, while the ERD may in some instances give larger responses to nonrigid than to rigid displacements, the subunits (and hence the ERD) are especially well behaved with continuous movement of rigid or smoothly deforming objects.

Elaborated Reichardt detectors

Probability summation and regional variation in contrast sensitivity across the visual field.

Summation and discrimination of gratings moving in opposite directions.

The perceived spatial frequency of low-frequency sinusoidal gratings is elevated when the gratings are temporally modulated sufficiently rapidly. Although this phenomenon is usually called ‘spatial-frequency doubling’, the magnitude of this spatial-frequency elevation depends on the spatial and temporal parameters of the grating and may be less than or greater than doubling. Adaptation to such a pattern produces contrast-threshold elevation whose spatial-frequency tuning is centred upon the grating's real rather than perceived spatial frequency. These results suggest that spatial-frequency elevation occurs later in the visual system than adaptation or that these two processes are independent of one another, at least under the conditions of these experiments.

/pdf/adaptation-to-a-spatial-frequency-doubled-stimulus-2gw47vk1ay.pdf

Adaptation to a "spatial-frequency doubled" stimulus.

Handle everyday research tasks with reliable, citation-backed results

Your personal Research Agent to handle research tasks with citation-backed results

Popular Tasks used by Researchers

How can I help with your research?

Meet SciSpace

Get more enhanced response by uploading the PDFs you want me to reference.

No relevant PDFs in your library

SciSpace is the AI research assistant for academics. Run systematic literature reviews on 280M+ papers, and write papers with cited sources. Trusted by 1M+ students, PhDs & researchers.

SciSpace | AI for Research

Analyze PDFs

Code & Manuscripts

Funding & Grants

Literature & Patents

Medical & Clinical Data

Systematic Review

Visualize & Present

Web & Data

Build a Google Scholar-like website for your research.

Build a website

Create charts and images for your research

Create a Chart

Write a paper for submission to a journal

Draft a manuscript

Patent Search

Design eye-catching scientific posters in minutes.

Scientific Poster Generation

Systematic Literature Review

One task is running at the moment. Your messages will be shown right after.

Drag and drop or click here to browse

Loved by <highlight>1 million+</highlight> researchers

Extract a list of specific topics and their sources from unstructured text

Topics

Compare and analyze relevant papers that matches with your search

Papers

Get insights from PDFs and bookmarked papers from your library

My library

Recent searches

Try searching for:

Catch AI-generated content in scholarly and non-scholarly content

{ai} Detector

Ai Writer

Get PDF Summaries, highlighted text explanations 

Chat with PDF

Effortlessly create in-text citations and bibliographies in APA and 2,500 other formats

Citation generator

Get explanations, summaries, and answers on academic papers

Ease up your research workflow with {scispace}'s cohort of exciting AI tools

Elevate your academic writing skills and convey your ideas the way you want

Paraphraser

Explore our range of reading and writing tools

Your file is being prepared and should be ready in a few minutes. If it's a large file, it might take a bit longer. You can close this window, and we'll email you the file when it's done.

You have reached a maximum limit of <strong>{limit}</strong> columns in the table. Remove at least <strong>1</strong> column to add or create another one.

Brian J. Murphy

Author Tools

Chat about Author

Papers

Summation and discrimination of gratings moving in opposite directions.

Adaptation to a "spatial-frequency doubled" stimulus.