Part I. Experimental Studies: 2. Experiment in psychology 3. Experiments on perceiving III Experiments on imaging 4-8. Experiments on remembering: (a) The method of description (b) The method of repeated reproduction (c) The method of picture writing (d) The method of serial reproduction (e) The method of serial reproduction picture material 9. Perceiving, recognizing, remembering 10. A theory of remembering 11. Images and their functions 12. Meaning Part II. Remembering as a Study in Social Psychology: 13. Social psychology 14. Social psychology and the matter of recall 15. Social psychology and the manner of recall 16. Conventionalism 17. The notion of a collective unconscious 18. The basis of social recall 19. A summary and some conclusions.

Remembering. A Study in Experimental and Social Psychology, Cambridge (University Press) 1964.

Objects and attention: the state of the art

The visual recognition of complex movements and actions is crucial for the survival of many species. It is important not only for communication and recognition at a distance, but also for the learning of complex motor actions by imitation. Movement recognition has been studied in psychophysical, neurophysiological and imaging experiments, and several cortical areas involved in it have been identified. We use a neurophysiologically plausible and quantitative model as a tool for organizing and making sense of the experimental data, despite their growing size and complexity. We review the main experimental findings and discuss possible neural mechanisms, and show that a learning-based, feedforward model provides a neurophysiologically plausible and consistent summary of many key experimental results.

Neural mechanisms for the recognition of biological movements.

Perceptual causality and animacy

Humans, being highly social creatures, rely heavily on the ability to perceive what others are doing and to infer from gestures and expressions what others may be intending to do. These perceptual skills are easily mastered by most, but not all, people, in large part because human action readily communicates intentions and feelings. In recent years, remarkable advances have been made in our understanding of the visual, motoric, and affective influences on perception of human action, as well as in the elucidation of the neural concomitants of perception of human action. This article reviews those advances and, where possible, draws links among those findings.

/pdf/perception-of-human-motion-2h7r5z9wbq.pdf

Perception of Human Motion

Limits of attentive tracking reveal temporal properties of attention

https://visionlab.harvard.edu/members/patrick/PDF.files/Sprite.pdf

Attention-based visual routines: sprites.

The interaction of the effects of luminance and spatial frequency on perception of suprathreshold contrast was studied with use of a contrast-matching paradigm. Four subjects matched the appearance of Gabor patches at different luminances and spatial frequencies. The contrast of a 1-octave Gabor test patch at one of five frequencies [1–16 cycles/degree (c/deg) in 1-octave steps] and at one of seven mean luminance levels (0.5–50 cd/m2 in 1/3-log-unit steps) was matched, by the method of adjustment to a standard patch of 3 c/deg at 50 cd/m2 at a nominal contrast of 0.3. For each block of trials the spatial frequency of the test patch was randomly changed (three repetitions at each frequency per block) while the luminance was fixed. The subject regularly shifted fixation between the two targets in response to a metronome tone every 1.5 s. Contrast constancy was demonstrated across the entire luminance range tested for all but the two highest frequencies. For 8 c/deg the perceived test contrast was reduced only when the luminance was less than 2 cd/m2. For 16 c/deg, perceived contrast decreased linearly (with a slope of −1/2 on a log scale) with decreases in luminance across the entire luminance range. As at threshold, reduction in luminance across the levels commonly available on a CRT display has only minimal effects on low-frequency suprathreshold contrast perception. However, the apparent contrast of high-frequency features, in binocular free-viewing conditions, is rapidly reduced with a local reduction in screen luminance. This effect has important implications for visual models used in image-quality analysis.

Contrast perception across changes in luminance and spatial frequency.

Short segments of two TV programs without audio description (AD) were presented to 25 subjects with low vision and 24 subjects with normal vision, and 29 additional subjects heard only the standard...

Evaluating Visual Information Provided by Audio Description.

Observers searched for a target walker (left or right facing) among 0, 1, 2, or 3 distractor walkers I n t r o d u c t i o n Johannson's point-light walkers remain one of the most powerful demonstrations of the way that motion can influence the perception of form Here, we explore the role that attention might be playing in the perception of these stimuli using a variety of different tasks M e t h o d R e s u l t s ¥ Search was serial ¥ However, items were processed very efficiently, taking into account estimates of attentional dwell time (Duncan, 1984) ¥ This is consistent with the notion that attention is required, but only to activate special purpose dynamic visual routines + Previously, we used a dual-task methodology to explore the nature of biological motion processing Observers were required to monitor a set of rectangles to detect a changing item, and at the same time discriminate the direction of a masked walking figure R e s u l t s Results showed that with simple, random motion masks, biological motion could be detected very effectively, even when attention was allocated to another task Does this mean that biological motion processing does not require attention? S u m m a r y Results from 10 observers. Target present responses shown as filled symbols. All observers completed two blocks, one with left, one with right facing targets Walkers were non-masked and subtended 4 and were equally spaced at random positions around a 4 viewing circle Here we used a flanker task to assess whether biological motion is mandatory. Do we process the direction of ignored walkers? Dual-task results may reflect very efficient processing of biological motion during short "switches" of attention Visual search results support the notion that attention is required to process direction of walking, but there is very little cost over and above an initial shift of focus Flanker data suggest that dynamic cues to direction are computed automatically, that is, biological motion processing may be mandatory R e f e r e n c e s In collaboration with Niko Troje (Ruhr-UniversitŠt, Bochum) and Douglas Cunningham (MPI, TŸbingen), we are now exploring search for gait using more real motion in virtual worlds 3D walking models are created via a motion capture system from Oxford Metrics (Vicon) and are then placed within a complex …

Angela T. Labianca

Papers

Limits of attentive tracking reveal temporal properties of attention

Attention-based visual routines: sprites.

Contrast perception across changes in luminance and spatial frequency.

Evaluating Visual Information Provided by Audio Description.

The role of attention in the processing of biological motion