Neuroophthalmology: a brief Vademecum.
The stunning, intricate interaction between the visual, vestibular and optomotor systems--each a miracle on its own--ensures maintenance of orientation in space as well as visual recognition and target selection despite a host of sensory conflicts and adversary disturbances. Their main goals are to keep a target of interest on the fovea by either maintaining or shifting the direction of gaze in order to produce an accurate internal representation of the visual surroundings, in particular the selected target, and to continuously mirror the spatial relationship between these various visual elements and the self. Not surprising, the implementation of this host of elaborate neural networks encompasses almost every part of the brain, including the brainstem, cerebellum, extrapyramidal system and many areas of the cerebral cortex. Thus far, these systems are among the best investigated in brain research; and enormous knowledge was amassed over the last century employing a variety of techniques, including single cell recordings, eye movement studies, functional imaging and neuropsychological observations. In addition, this prolific line of research has enlightened many fundamental principles of neural and neuronal processing, which have subsequently enriched other fields of brain research as well as computational neuroscience, e.g. the discovery of receptive fields, which have now become a ubiquitous concept in many other areas of neurophysiology. This (improperly) brief, fractional and undoubtedly biased Vademecum is meant to accompany the reader into this marvellous field of neurophysiology and neurology. In particular, it stresses the clinical application of its functional neuroanatomy at the bedside, which, in many respects, is superior to other means of investigating a patient.