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This chapter considers the visual capabilities of the normal newborn infant, starting with crude visual orienting behaviour towards visually conspicuous objects. The evidence for a specific ability in newborns to recognize face configurations, and its possible neural underpinnings is reviewed. Studies that measure the development of acuity and contrast sensitivity from birth are discussed, including the likely optical, retinal, and neural factors limiting these processes, and the relationship between measurements based on preferential looking and those obtained by VEP/VERP methods. It presents data from two unique intensive longitudinal studies of the author's daughters, Fleur and Ione, on development of contrast sensitivity and acuity. The results show that compared across many testing sessions, OKN (optokinetic nystagmus), VEPs, and preferential looking measures show broad agreement in the time course of development of contrast sensitivity.

This chapter discusses research results, mainly from the author's research team, providing evidence for the first stages of the neurobiological model, showing sequential onset of different selective channels in visual cortex. Colour processing is weak or absent at birth, but emerges in the first three months. The novel VEP method developed in the Visual Development Unit is described, showing the onset of cortical orientation selectivity, with related behavioural evidence for infants' orientation discrimination. For motion selectivity, optokinetic nystagmus (OKN) shows an early subcortical directional mechanism, with characteristic monocular asymmetries. At two to three months, VEP evidence shows a cortical directional mechanism, which also contributes to symmetrical OKN. VEP and behavioural methods show cortical responses to binocular correlation and disparity, first appearing at three-four months. This is discussed in relation to vergence control, strabismus, stereo depth perception, and how the pre-binocular cortex may be organized.

This chapter reviews neurobiological correlates of visual pattern masking at cortical levels in primates. A first part is devoted to evidence from animal studies. The review includes investigations of metacontrast and pattern masking in area V1, para- and metacontrast in area V4, backward pattern masking in frontal eye field and in temporal cortex. The second part of the chapter reviews evidence from human studies and includes discussions of studies using the Visual Evoked Potential (VEP) and the functional magnetic resonance (fMRI) techniques.

This chapter discuses various potential recording methods of ophthalmology. The electro-oculogram (EOG) is described as a registration of the increase in the corneoretinal potential caused by an increase of the illumination of the retina. The use of visual evoked potentials (VEPs) are used for the application of the visual pathway conduction, misrouting, and objective visual acuity measurement. The applications and standardized protocol of electroretinograms (ERG) have also been finalized. VEP brain maps are combined with brain-imaging techniques, such as magnetic resonance imaging (MRI) and single photon emission computed tomography (SPECT), to interpret these recordings in ophthalmology.

When your child is first diagnosed with aniridia or WAGR syndrome, you will have several questions for your child’s ophthalmologist. To be prepared for the first appointment, the best thing to do is make a list of questions. Some questions other parents have had are listed at the end of this chapter. If you choose to, you can use these as a starting point and add more questions to the list as you think of them. At the appointment, be sure to have your list of questions to ask the doctor. Be sure to repeat what the doctor has told you to make sure you understand him or her. If you’re not sure, then ask the doctor to try to explain it in a different way so you can understand. It is your child, and you should be as informed as possible, and the only way to do that is to ask questions and to have a good relationship with your child’s ophthalmologist. Other questions parents have had that you do not necessarily need to ask an ophthalmologist will be discussed in this chapter. When a child is first diagnosed, a question asked by many parents, especially mothers, is, “Was this my fault?” No, it was not. Do not ever blame yourself for your child having aniridia or WAGR syndrome. It is a genetic disorder that you could not have done anything about, unless you do have it yourself. There is no reason for you to feel guilty or to put blame on yourself for something you had no control over. One way to help get over any of these feelings is to join Aniridia Foundation International, where you can meet many other parents and people with aniridia. From meeting and speaking with them, you can get the support you need. . On AFI’s members’ area website, I asked parents, “What questions did you have when your child was diagnosed?” One mother responded, “Mainly I wish someone had told us that he would be able to see at least a little bit and that the disastrous picture that was painted for us at the start was not actually representative of what he would turn out to be.”

This chapter discusses a method for obtaining a novel visual event-related potential known as the visual evoked spread spectrum analysis (VESPA) that seeks to address the limitations of the standard visual evoked potential (VEP). It introduces the broader reverse correlation technique that has seen widespread use in the analysis of many physiological systems. The chapter describes the VESPA method itself, including the differences between the standard VEP and the VESPA, and some proposed applications and extensions, and shows that VESPA may actually reflect mostly activity of parvocellular pathways. The auditory and visual responses demonstrated in the chapter indicate the utility of the VESPA method in investigation of multisensory integration processes.