The visual system has emerged as a premier model for understanding information processing by neurons. Within vision, the submodality of color provides a particularly attractive experimental platform: we know a tremendous amount about the phenomenology of color perception and can explain some aspects of color perception, quantitatively and with high precision, by well- understood physiological processes. As a result of this progress, we can quickly and accurately diagnose many distinct forms of color blindness and can build devices that render colors accurately. On the other hand, our understanding of the neurophysiology of color vision is largely restricted to the retina. The central mechanisms of color vision are largely unknown, and many aspects of color perception cannot be explained by retinal mechanisms. The proposed research is to measure the quality and behavioral relevance of the signals beyond the retina that mediate color vision.
Two specific aims are planned: 1) Single neuron recording in the primary visual cortex to identify the neurons most likely to underlie color vision. 2) Single neuron recording in the primary visual cortex to study how manipulations that affect color appearance affect neuronal responses. The proposed experiments extend our knowledge of color vision toward an understanding of the principles of neuroscience that give rise to perception and its disorders. Such an understanding promises to provide the means to promote recovery of visual function following trauma or neurological disease.
Understanding how neurons mediate perception is an important step towards developing effective treatments for pathologies that disrupt perception. The proposed experiments exploit the model system of color vision, one of the most mature submodalities of vision, to reveal the neural events that relate activation of the peripheral receptors to perception.
|Weller, J Patrick; Horwitz, Gregory D (2017) Measurements of neuronal color tuning: Procedures, pitfalls, and alternatives. Vision Res :|
|Hass, Charles A; Angueyra, Juan M; Lindbloom-Brown, Zachary et al. (2015) Chromatic detection from cone photoreceptors to V1 neurons to behavior in rhesus monkeys. J Vis 15:1|
|Horwitz, G D (2015) What studies of macaque monkeys have told us about human color vision. Neuroscience 296:110-5|
|Lindbloom-Brown, Zachary; Tait, Leah J; Horwitz, Gregory D (2014) Spectral sensitivity differences between rhesus monkeys and humans: implications for neurophysiology. J Neurophysiol 112:3164-72|
|Hass, Charles A; Horwitz, Gregory D (2013) V1 mechanisms underlying chromatic contrast detection. J Neurophysiol 109:2483-94|
|Jazayeri, Mehrdad; Lindbloom-Brown, Zachary; Horwitz, Gregory D (2012) Saccadic eye movements evoked by optogenetic activation of primate V1. Nat Neurosci 15:1368-70|
|Horwitz, Gregory D; Hass, Charles A (2012) Nonlinear analysis of macaque V1 color tuning reveals cardinal directions for cortical color processing. Nat Neurosci 15:913-9|
|Hass, Charles A; Horwitz, Gregory D (2011) Effects of microsaccades on contrast detection and V1 responses in macaques. J Vis 11:1-17|
|Conway, Bevil R; Chatterjee, Soumya; Field, Greg D et al. (2010) Advances in color science: from retina to behavior. J Neurosci 30:14955-63|