NEUROVISION: NEURAL BASES OF BINOCULAR VISION AND COORDINATION AND THEIR IMPLICATIONS IN VISUAL TRAINING PROGRAMS
The Topic Editor is Olivier A. Coubard from The Neuropsychological Laboratory, CNS-Fed, France who introduces the volume as follows:
Binocular vision is achieved by five neurovisual systems originating in the retina but varying in their destination within the brain. Two systems have been widely studied: the retino-tectal or retino-collicular route, which subserves an expedient and raw estimate of the visual scene through the magnocellular pathway, and the retino-occipital or retino-cortical route, which allows slower but refined analysis of the visual scene through the parvocellular pathway. But there also exist further neurovisual systems: the retino-hypothalamic, retino-pretectal, and accessory optic systems, which play a crucial role in vision though they are less understood. The retino-pretectal pathway projecting onto the pretectum is critical for the pupillary or photomotor reflex. The retino-hypothalamic pathway projecting onto the suprachiasmatic nucleus regulates numerous behavioral and biological functions as well as circadian rhythms. The accessory optic system targeting terminal lateral, medial and dorsal nuclei through the paraoptic fasciculus plays a role in head and gaze orientation as well as slow movements. Taken together, these neurovisual systems involve 60% of brain activity, thus highlighting the importance of vision in the functioning and regulation of the central nervous system.
But vision is first and foremost action, which makes perception impossible without movement. Binocular coordination is a prerequisite for binocular fusion of the object of interest on the two foveas, thus ensuring visual perception. The retino-collicular pathway is sufficient to elicit reflexive eye movements with short latencies. Thanks to its motor neurons, the superior colliculus activates premotor neurons, which themselves activate motor neurons of the oculomotor, trochlear and abducens nuclei. At a higher level, a cascade of neural mechanisms participates in the control of decisional eye movements. The superior colliculus is controlled by the substancia nigra pars reticulata, which is itself gated by subcortical structures such as the dorsal striatum. The superior colliculus is also inhibited by the dorsolateral prefrontal cortex through a direct prefrontotectal tract. Cortical areas are crucial for the triggering of eye movements: the frontal eye field, supplementary eye field, and parietal eye field. Finally the cerebellum maintains accuracy.
The focus of the present research topic, entitled Neural bases of binocular vision and coordination and their implications in visual training programs, is to review the most recent findings in brain imaging and neurophysiology of binocular vision and coordination in humans and animals with frontally-placed eyes. The emphasis is put on studies that enable transfer of knowledge toward visual training programs targeting visual field defects (e.g., hemianopia) and binocular functional disorders (e.g., amblyopia).
You can download the work in its entirety through the link above, and here is a snapshot of the chapter titles:
PART I – NEURAL BASES OF EYE MOVEMENTS AND BINOCULAR COORDINATION
Fixational eye movements and binocular vision
What makes a frontal area of primate brain the frontal eye field?
Saccade-related activity in the prefrontal cortex: its role in eye movement control and cognitive functions
The amblyopic eye in subjects with anisometropia show increased saccadic latency in the delayed saccade task
Binocular saccade coordination in reading and visual search: a developmental study in typical reader and dyslexic children
LATER models of neural decision behavior in choice tasks
PART II – NEURAL BASES OF VISUAL PERCEPTION AND BINOCULAR VISION
Cortical and white matter mapping in the visual system-more than meets the eye: on the importance of functional imaging to understand visual system pathologies
Origins of strabismus and loss of binocular vision
Neuroimaging of amblyopia and binocular vision: a review
The neural bases of spatial frequency processing during scene perception
Differential processing of natural scenes in posterior cortical atrophy and in Alzheimer’s disease, as measured with a saccade choice task
What visual illusions teach us about schizophrenia
PART III – VISUAL TRAINING PROGRAMS IN ORGANIC DEFICITS AND THEIR NEURAL BASES
Implications of CI therapy for visual deficit training
Rehabilitation of homonymous hemianopia: insight into blindsight
Visualizing the blind brain: brain imaging of visual field defects from early recovery to rehabilitation techniques
Functional activity within the frontal eye fields, posterior parietal cortex, and cerebellar vermis significantly correlates to symmetrical vergence peak velocity: an ROI-based, fMRI study of vergence training
Frontal eye field, where art thou? Anatomy, function, and non-invasive manipulation of frontal regions involved in eye movements and associated cognitive operations
What saccadic eye movements tell us about TMS-induced neuromodulation of the DLPFC and mood changes: a pilot study in bipolar disorders