http://apsychoserver.psychofizz.psych.arizona.edu/JJBAReprints/PSYC501A/Readings/Polich_2007_Clin_Neurophys_Review_P3s.pdf

Updating P300: An Integrative Theory of P3a and P3b

The event-related potential (ERP) technique in cognitive neuroscience allows scientists to observe human brain activity that reflects specific cognitive processes. In An Introduction to the Event-Related Potential Technique, Steve Luck offers the first comprehensive guide to the practicalities of conducting ERP experiments in cognitive neuroscience and related fields, including affective neuroscience and experimental psychopathology. The book can serve as a guide for the classroom or the laboratory and as a reference for researchers who do not conduct ERP studies themselves but need to understand and evaluate ERP experiments in the literature. It summarizes the accumulated body of ERP theory and practice, providing detailed, practical advice about how to design, conduct, and interpret ERP experiments, and presents the theoretical background needed to understand why an experiment is carried out in a particular way. Luck focuses on the most fundamental techniques, describing them as they are used in many of the world's leading ERP laboratories. These techniques reflect a long history of electrophysiological recordings and provide an excellent foundation for more advanced approaches. The book also provides advice on the key topic of how to design ERP experiments so that they will be useful in answering questions of broad scientific interest. This reflects the increasing proportion of ERP research that focuses on these broader questions rather than the "ERPology" of early studies, which concentrated primarily on ERP components and methods. Topics covered include the neural origins of ERPs, signal averaging, artifact rejection and correction, filtering, measurement and analysis, localization, and the practicalities of setting up the lab.

/pdf/an-introduction-to-the-event-related-potential-technique-38ksmp4fjp.pdf

An Introduction to the Event-Related Potential Technique

Many current neurophysiological, psychophysical, and psychological approaches to vision rest on the idea that when we see, the brain produces an internal representation of the world. The activation of this internal representation is assumed to give rise to the experience of seeing. The problem with this kind of approach is that it leaves unexplained how the existence of such a detailed internal representation might produce visual consciousness. An alternative proposal is made here. We propose that seeing is a way of acting. It is a particular way of exploring the environment. Activity in internal representations does not generate the experience of seeing. The outside world serves as its own, external, representation. The experience of seeing occurs when the organism masters what we call the governing laws of sensorimotor contingency. The advantage of this approach is that it provides a natural and principled way of accounting for visual consciousness, and for the differences in the perceived quality of sensory experience in the different sensory modalities. Several lines of empirical evidence are brought forward in support of the theory, in particular: evidence from experiments in sensorimotor adaptation, visual \"filling in,\" visual stability despite eye movements, change blindness, sensory substitution, and color perception.

A sensorimotor account of vision and visual consciousness-Authors' Response-Acting out our sensory experience

Many current neurophysiological, psychophysical, and psychological approaches to vision rest on the idea that when we see, the brain produces an internal representation of the world. The activation of this internal representation is assumed to give rise to the experience of seeing. The problem with this kind of approach is that it leaves unexplained how the existence of such a detailed internal representation might produce visual consciousness. An alternative proposal is made here. We propose that seeing is a way of acting. It is a particular way of exploring the environment. Activity in internal representations does not generate the experience of seeing. The outside world serves as its own, external, representation. The experience of seeing occurs when the organism masters what we call the governing laws of sensorimotor contingency. The advantage of this approach is that it provides a natural and principled way of accounting for visual consciousness, and for the differences in the perceived quality of sensory experience in the different sensory modalities. Several lines of empirical evidence are brought forward in support of the theory, in particular: evidence from experiments in sensorimotor adaptation, visual “filling in,” visual stability despite eye movements, change blindness, sensory substitution, and color perception.

/pdf/a-sensorimotor-account-of-vision-and-visual-consciousness-1o8kf5szfs.pdf

A sensorimotor account of vision and visual consciousness

Let's read! We will often find out this sentence everywhere. When still being a kid, mom used to order us to always read, so did the teacher. Some books are fully read in a week and we need the obligation to support reading. What about now? Do you still love reading? Is reading only for you who have obligation? Absolutely not! We here offer you a new book enPDFd the perception of the visual world to read.

The Perception of the Visual World. By James J. Gibson. U.S.A.: Houghton Mifflin Company, 1950 (George Allen & Unwin, Ltd., London). Price 35s.

Recognition and detection of texture-defined letters.

The Committee on Ophthalmic Procedures Assessment of the American Academy of Ophthalmology suggested either contrast sensitivity or low-contrast visual acuity (VA) measured before and after adding a glare source as a test for assessing overall visual disability from immature cataracts. We have developed a test that follows the Committee's three principles of design, and we report that the effect of glare on VA is considerably greater for recognizing low-contrast letters than for recognizing high-contrast letters. The effect of glare on VA increases progressively as letter contrast is reduced from 96% through 50%, 25%, 11%, and 4%. The 25% chart (and possibly the 11% chart) gives the most suitable sensitivity for eyes with immature cataracts

Measurement of glare susceptibility using low-contrast letter charts.

The ability to set the angle of a 'V' to a designated value in the following three conditions was compared: (1) verbal designation of V angle; (2) initial 30 s visual demonstration of the designated V angle; (3) verbal designation of V angle plus feedback after every setting. The designated angles were 90 degrees and 45 degrees plus three arbitrary angles (65 degrees, 125 degrees, and 145 degrees). Each run comprised thirty consecutive settings. To ensure that our observers based their settings entirely on V angle it was arranged that line orientation did not provide a reliable cue to V angle. In condition (1), accuracy of setting V angle was significantly worse when the designated angle was other than 90 degrees or 45 degrees. This was not the case in condition (2), indicating that observers maintained a memory of the initial demonstration throughout a run of thirty settings. Setting error was not significant in condition (3) for any of the five angles. However, even in condition (3), setting-to-setting variability was significantly lower for the 90 degrees angle than for the other angles.

Accuracy of Reproducing Angles: Is a Right Angle Special?

Two-dimensional Aspect Ratio Discrimination for Shape Defined by Orientation Texture

Psychophysical evidence supports the idea that the human visual pathway computes an object's rate of change of angular size rather independently of the object's trajectory and rather independently of other visual parameters, including contrast and intensity. This independence could provide a basis for accurately judging the component of an object's velocity along a line through the eye in the working visual environment where many visual parameters vary simultaneously. We describe a procedure for quantifying a subject's ability to track changing size, and illustrate the procedure with preliminary experimental data. The subject's R.M.S. tracking errors are displayed in three frequency bands. Our device also measures the perturbing effect of sideways motion upon the subject's ability to track changing size. Such data may go some way to predict a subject's performance in tasks of eye-limb coordination, especially where visual information is largely restricted to the changing-size channel. Language: en

David Regan

Papers

Recognition and detection of texture-defined letters.

Measurement of glare susceptibility using low-contrast letter charts.

Accuracy of Reproducing Angles: Is a Right Angle Special?

Two-dimensional Aspect Ratio Discrimination for Shape Defined by Orientation Texture

Device for measuring the precision of eye-hand coordination while tracking changing size