A fundamental feature of the mammalian visual system is its decomposition of the visual image into specialized streams of information, some dedicated to processing motion, others to object shape or color. Although these channels have been well-defined from their origin in the retina to several regions of the visual cortex, less is known about how they are eventually re-integrated to obtain accurate interpretations of the visual world. We are currently investigating how two different motion-processing pathways in the visual cortex of the macaque (a direct V1-MT pathway and an indirect V1-V2A/3-MT pathway), combine information to obtain accurate interpretations of how objects move. We are doing this by using a reversible-inactivation technique (localized cooling) to silence neuronal activity of areas V2 and V3 in the awake behaving macaque. By recording from neurons in the motion-processing area MT and recording ocular behavior, we will identify the specific visual deficiencies that arise when the above extrastriate areas do not contribute to the analysis of motion.
| Ponce, Carlos R; Hunter, J Nicholas; Pack, Christopher C et al. (2011) Contributions of indirect pathways to visual response properties in macaque middle temporal area MT. J Neurosci 31:3894-903 |
| Ponce, Carlos R; Lomber, Stephen G; Born, Richard T (2008) Integrating motion and depth via parallel pathways. Nat Neurosci 11:216-23 |
