Superstitious Perceptions Reveal Properties of Internal Representations (original) (raw)

Echoes of Vision: Mental Imagery in the Human Brain

2019

When you picture the face of a friend or imagine your dream house, you are using the same parts of your brain that you use to see. How does the same system manage to both accurately analyze the world around it and synthesize visual experiences without any external input at all? We approach this question and others by extending the well-established theory that the human visual system embodies a probabilistic generative model of the visual world. That is, just as visual features co-occur with one another in the real world with a certain probability (the feature “tree” has a high probability of occurring with the feature “green”), so do the patterns of activity that encode those features in the brain. With such a joint probability distribution at its disposal, the brain can not only infer the cause of a given activity pattern on the retina (vision), but can also generate the probable visual consequence of an assumed or remembered cause (imagery). The formulation of this model predicts ...

Internal vs. external information in visual perception

Proceedings of the Second International Symposium on Smart Graphics, 2002

One of the more compelling beliefs about vision is that it i s based on representations that are coherent and complete, with everything in the visual field described in great detail. However, changes made during a visual disturbance are found to be difficult to see, arguing against the idea that our brains contain a detailed, picture-like representation of the scene. Instead, it is argued here that a more dynamic, just-in-time representation is involved, one with deep similarities to the way that users interact with external displays.

Understanding vision in wholly empirical terms

Proceedings of the National Academy of Sciences, 2011

This article considers visual perception, the nature of the information on which perceptions seem to be based, and the implications of a wholly empirical concept of perception and sensory processing for vision science. Evidence from studies of lightness, brightness, color, form, and motion all indicate that, because the visual system cannot access the physical world by means of retinal light patterns as such, what we see cannot and does not represent the actual properties of objects or images. The phenomenology of visual perceptions can be explained, however, in terms of empirical associations that link images whose meanings are inherently undetermined to their behavioral significance. Vision in these terms requires fundamentally different concepts of what we see, why, and how the visual system operates.

The psychophysics of imagery

Perception & Psychophysics, 2000

A series of experiments considers the extent to which the interrelations among subjective magnitudes aroused by images corresponds to those for subjective magnitudes aroused by physical stimuli. In Experiment 1,68 undergraduates typed phrases in response to graded categories regarding the imagined magnitude of lights, sounds, and smells. In Experiment 2, 5 undergraduates and, in Experiment 3, 3 graduate students then magnitude estimated the image intensity aroused by each of these stimulus phrases. In Experiments 4 and 5, the same subjects performed cross-modality matches between phrases arousing images for different attributes (light, sound, and smell). Statistical analysis indicates that estimates based on images display many of the same patterns as those based on physical stimuli. The major exception involves sequence effects, present for actual stimuli but not for images. An outstanding issue in cognitive psychology centers on the degree to which the subjective magnitude aroused by an image corresponds to that aroused by the physical stimulus itself (Finke, 1985; Kosslyn, 1987; Shepard & Cooper, 1982). Empirical evidence supports the view that many of the brain structures underlying perceptual, primarily visual, processes are the same as those responsible for imagery (

The nature of visual perception: could a longstanding debate be resolved empirically?

Journal of Mind and Behaviour, 2023

There is a deep divide between people’s direct experiences and the standard understand- ing of vision as taught in biology and psychology. When the looker cannot be seen and other sensory cues are excluded, the sense of being stared at, also called scopaesthesia, is impossible from the conventional point of view. Yet it seems to happen. Here, we suggest that thinking again about this puzzle, instead of ignoring or denying it, could deepen our understanding of vision and stimulate fruitful research in the life and mind sciences. The evolution of brain processes that imply a movement of influences out of the eyes would make more sense if such influences actually occur than if they are an illusion. Could sco- paesthesia actually happen? No, not if minds are inside heads. But what if minds are not confined to brains?

Psychophysical Analyses of Perceptual Representations.

1995

Abstract: This report is divided into two parts. The first part describes studies done at the University of Minnesota. The second part describes studies done at the University of Southern California. In both cases, full lists of citations are given to work supported in full or in part by this grant. Because most of these projects have been described in detail in previous reports, the purpose of this final report is to provide summary of the many studies and a complete list of citations.